Re: [time-nuts] Bodnar "Precision Frequency Reference (GPS Clock)" AND LeoNTP Networked Time NTP Server Questions

[Didier Juges]

A shield will definitely help with differential mode noise (the USB
communication signal) but has little effect on common mode noise (the
digital stuff coming from other parts of the circuit), a choke is the fix
for common mode (if you can't get rid of the noise at the source, or
otherwise return common mode noise directly back to earth instead of
through the cable).

Didier KO4BB

On Fri, May 18, 2018, 8:10 AM Clint Jay  wrote:

> Interested to know how much noise would be from USB signalling and how much
> is " machine noise"  from the PC as my understanding of USB signalling is
> that it's differential so such should be low noise?
>
> I'm also not sure I've ever seen a non screened usb cable?
>
> On Fri, 18 May 2018 1:17 pm Dana Whitlow,  wrote:
>
> > Caution, folks, about USB cable radiation.  While the intended signals
> > flowing through the
> > cable presumably contribute a bit to the overall picture, common-mode
> > currents on the cable
> > are the most likely cause of severe radiation problems.  These currents
> > arise not merely from
> > intended USB signals, but from *all* the digital activity within the
> > device, and will be present
> > whether or not USB communications are going on.
> >
> > The keys to controlling this problem are:
> >
> > 1) Shielding on the USB cable.
> > 2) Proper design inside the USB device, rarely done beyond the point of
> > (barely) meeting
> >  government regulations, which are far too forgiving IMHO.
> > 3) Use of a ferrite choke on the cable to reduce those residual currents
> > that get by anyway.
> >
> > Note that only item 3 might be under the control of the user to any
> useful
> > extent.
> >
> > So please don't just assume that using a USB cable for charging only
> solves
> > anything.
> >
> > Note that the above comments are also generally applicable to *all
> *cables,
> > including power
> > cables, that are plugged into *any* digital device.
> >
> > DanaK8YUM
> >
> >
> >
> > On Fri, May 18, 2018 at 5:15 AM, David J Taylor via time-nuts <
> > time-nuts@febo.com> wrote:
> >
> > > Anyone who is using one (or both) of these, and/or folks who have a
> > > logical opinion:
> > > []
> > > There's more...  but this is a good start.  Just want to try and get
> > > parts on the way.  Have to build a separate outboard regulator for the
> > > timing GPS antenna, too.
> > >
> > > Thanks!
> > >
> > > Clay Autery
> > > =
> > >
> > > Clay,
> > >
> > > I have all three of these units, all powered off USB.  I don't see any
> > > reason why you shouldn't use a USB cable with just the DC part
> connected,
> > > so that there's no issue about radiation.  A standard USB port would
> only
> > > supply 0.5A so that's an upper limit on the power consumption.  If
> it's a
> > > very long USB cable (you mention mast-head) check the resistance.
> > >
> > > As a crude guide...
> > >
> > > - The (larger box) NTP server feels cold to the touch.
> > >
> > > - The smaller, single output frequency source feels very slightly warm
> to
> > > the touch (feeding an Icom IC-R8600)
> > >
> > > - The larger, dual-output frequency source feels slightly warm to the
> > > touch.
> > >
> > > There's an e-mail address where you could ask:  supp...@leobodnar.com
> > >
> > > Cheers,
> > > David
> > > --
> > > SatSignal Software - Quality software written to your requirements
> > > Web: http://www.satsignal.eu
> > > Email: david-tay...@blueyonder.co.uk
> > > Twitter: @gm8arv
> > > ___
> > > time-nuts mailing list -- time-nuts@febo.com
> > > To unsubscribe, go to https://www.febo.com/cgi-bin/m
> > > ailman/listinfo/time-nuts
> > > and follow the instructions there.
> > >
> > ___
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> >
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Re: [time-nuts] Setting correct date on Trimble Thunderbolt receiver

[Didier Juges]

Tom,

In my TB monitor kit, I used your Julian date routines, adapted to the 8051
(no variable greater than 32 bits since my compiler does not support them
either) to apply the GPS offset correction.
It was very helpful.

Didier KO4BB

On Wed, Mar 28, 2018, 7:13 AM Tom Van Baak  wrote:

> Hi Mark,
>
> > Heather keeps all times as a double precision Julian date.  Using
> Heather's code can
> > be a problem on Arduinos since their "double" precision numbers are
> actually 32 bit
> > single precision,  so you would need to do some more complicated math.
>
> Ah, more complicated math to solve a problem vs. simpler math to avoid a
> problem in the first place.
>
> Here's a simple "GPS Day Number" example: www.leapsecond.com/tools/gpsdn.c
>
> To add 1024 weeks to a given date use:
>
> gpsdn = date_to_gpsdn(year, month, day);
> gpsdn += 1024 * 7;
> gpsdn_to_ymd(gpsdn, , , );
>
> That's it. It uses 32 bit integers; no floating point required; works on
> any OS, or Arduino.
>
> /tvb
>
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Re: [time-nuts] Recommendations for Mains Power Monitor / Logger

[Didier Juges]

I like the sound card idea. However I believe it's much better to use the
two channels. At least under Windows, it is much easier to track the
relative phase of the two channels of one sound card than the absolute
phase of one channel compared to the system clock.
I have written an audio VNA in Visual Basic that has all the building
blocks.
Unfortunately, it is harder and harder to develop VB 6.0 under Windows 10
so I am not doing much of that anymore.
Since I am doing it using FFT, filtering (and harmonics measurements) come
for free.

On Mar 10, 2018 10:47 PM, "Tom Van Baak"  wrote:

> > I've done some Googling and have found any number of designs.
>
> Pat,
>
> 1) Safety. I usually use a low voltage step-down transformer. This gives
> isolation and safety. Anything from 3 VAC to 24 VAC is fine.
>
> 2) Trigger. There are dozens of schematics on the web for capturing the
> zero-crossing of a low-voltage sine wave. You can easily go overboard on
> this. Or just keep it simple and feed the signal through a resistor
> directly into a microprocessor input. The internal clamping diodes do their
> thing. A Schmitt trigger input is helpful but not necessary depending on
> how your software makes the measurement.
>
> 3) Timebase. Given the long-term accuracy of mains (seconds a day, seconds
> a year) you don't need an atomic timebase. If you collect data for a couple
> of days any old XO will be fine. If you plan to collect data for months you
> may want a OCXO. Most of us just use cheap GPS receivers.
>
> 4) Measurement. There are many ways to measure the signal. You can measure
> frequency directly, as with a frequency counter. You get nice data but it
> may not be perfect long-term due to dead time or gating effects in the
> counter.
>
> So what most of us do is measure phase (time error) instead. One way is to
> make time interval measurements from a given mains cycle to a GPS 1PPS tick
> or vice versa, from each GPS/1PPS tick to the very next mains cycle. Either
> way you get about sample per second. If you're in search of perfection it
> gets a bit tricky when the two signals are in a coincidence zone.
>
> The other approach is not to use a frequency or time interval counter at
> all. Instead you timestamp each cycle, or every 60th cycle. Unix-like
> systems have this capability. See Hal's posting. I use a picPET, a PIC
> microcontroller that takes snapshots of a free-running decimal counter
> driven by a 10 MHz timebase (OCXO or GPSDO).
>
> The advantage of the timestamp method is that you don't ever miss samples,
> you can time every cycle (if you want), or throw away all but one sample
> per second or per 10 seconds or per minute, etc. And best of all,
> timestamping avoids the hassles of the coincidence zone.
>
> 5) CPU. A plain microcontroller, or Arduino, or R-Pi can be used. Or if
> you're on Windows and have a native or USB serial port try this simple tool
> as a demo:
>
> http://leapsecond.com/tools/pctsc.exe
> http://leapsecond.com/tools/pctsc.c
>
> 6) An assortment of mains links:
>
> http://leapsecond.com/pages/mains/
> http://leapsecond.com/pages/mains-cv/
> http://wwwhome.cs.utwente.nl/~ptdeboer/misc/mains.html
> http://leapsecond.com/pages/mains/mains-adev-mdev-gnuplot-g4.png
> http://leapsecond.com/pages/tec/mains-clock-ani.gif
> http://leapsecond.com/pages/ac-detect/
> http://leapsecond.com/pic/picpet.htm
> http://leapsecond.com/pic/pp06.htm
>
> 7) Final comments.
>
> It is tempting to worry about the design, as they are so many out there on
> the web. Which is best? What are the pitfalls? What about noise immunity?
> What about precision and accuracy? My recommendation is not to over-think
> this. Just throw something together and see what you've got. Most of the
> work is with handling the data you get, doing the math, making plots, etc.
> If after the first day you see odd-looking 16 ms jumps in your data then
> you know you need to pay more attention to trigger level or noise issues.
>
> 8) A sound idea.
>
> We need someone to try out the sound card method. Send the isolated low
> voltage AC into the L channel and a GPS 1PPS into the R channel. "The rest
> is just software." Note that because you have access to the entire sine
> wave there's a lot you can do with this method besides making charts of
> time drift or frequency deviation from the zero-crossings.
>
> For an even cheaper solution, forget the GPS receiver and the R channel --
> since the PC (if running NTP) already knows the correct time. And skip the
> AC transformer too -- instead just hang a foot of wire off the L channel
> input. There's mains hum everywhere. It would be the one time in your life
> where the ever-present audio hum actually has a good use.
>
> /tvb
>
> - Original Message -
> From: "Patrick Murphy" 
> To: 
> Sent: Saturday, March 10, 2018 2:53 PM
> Subject: [time-nuts] Recommendations for Mains Power Monitor / Logger
>
>
> All this 

Re: [time-nuts] Replacement A9 boards for the HP 5065A

[Didier Juges]

It depends on the quantity they buy. I just looked for X7R 0.1uF in 0805 at
Digikey and the automotive grade (10%, -55 to +125) is cheaper than the non
automotive grade with worse tolerance and more limited temperature range.
Next time you buy it may be reversed...

On Feb 25, 2018 1:51 PM, "Gerhard Hoffmann"  wrote:

>
>
> Am 25.02.2018 um 13:46 schrieb Azelio Boriani:
>
>> The part number BFC234421475, on 
>> seems to be a Philips product, 2500 available, for 49.28 UAH
>> (Ukrainian Hryvnia, that is 1.77 USD). A mysterious capacitor...
>>
> Why not go to Mouser or DK, as usual?
>
> Or to the source itself:
> <  https://www.wima.de/en/  >
>
> (Abt. an hour of driving from where I'm now).
>
> BTW last time I bought some at DK/Mouser, there was
> a pricing artefact, in that 5% was cheaper than 10%
>
> :-)  Gerhard
>
>
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Re: [time-nuts] Furuno GT-8031 breakout board

[Didier Juges]

Got the answer in the previous email :)

On Mon, Feb 19, 2018 at 5:28 PM Didier Juges <shali...@gmail.com> wrote:

> What do you mean by “Adafruit” pinout?
>
> On Fri, Feb 16, 2018 at 11:50 AM Mark Sims <hol...@hotmail.com> wrote:
>
>> No, the Tbolt does not have a separate receiver board... plus its' GPS is
>> rather special... the RF chain is locked to the OCXO so it does not produce
>> any sawtooth error.
>>
>> The Lucent KS firmware expects the GPS to support the older 6/8 channel
>> messages.   The newer 12 channel  messages are different.
>>
>> BTW, I just did a Motorola M12 to Adafruit pinout board.  The M12 form
>> factor and pinouts are also used by a lot of other timing receivers.  Why
>> Adafruit?  Because it is breadboard friendly,  has enough pins for all the
>> signals that one expects,  and my GPS to RS-232 adapter board has an
>> Adafruit connector on it.
>>
>> 
>>
>> > Never having opened my TBolt, are the GT-8736 boards of use to replace
>> the aging and partly deaf receiver in that? Or for a KS-24019?
>> ___
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Re: [time-nuts] Furuno GT-8031 breakout board

[Didier Juges]

What do you mean by “Adafruit” pinout?

On Fri, Feb 16, 2018 at 11:50 AM Mark Sims  wrote:

> No, the Tbolt does not have a separate receiver board... plus its' GPS is
> rather special... the RF chain is locked to the OCXO so it does not produce
> any sawtooth error.
>
> The Lucent KS firmware expects the GPS to support the older 6/8 channel
> messages.   The newer 12 channel  messages are different.
>
> BTW, I just did a Motorola M12 to Adafruit pinout board.  The M12 form
> factor and pinouts are also used by a lot of other timing receivers.  Why
> Adafruit?  Because it is breadboard friendly,  has enough pins for all the
> signals that one expects,  and my GPS to RS-232 adapter board has an
> Adafruit connector on it.
>
> 
>
> > Never having opened my TBolt, are the GT-8736 boards of use to replace
> the aging and partly deaf receiver in that? Or for a KS-24019?
> ___
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Re: [time-nuts] On the IETF leap-seconds.list SHA1

[Didier Juges]

I am so glad that my laziness has a new name that does not sound nearly as
bad as the original one...

I will be sure to remember that next time I do my "self appraisal".

Merry Christmas everyone (I know I am early but my clock is fast...)

Didier KO4BB


On Thu, Dec 21, 2017 at 2:08 AM, Mike Cook  wrote:

>
>   A case of « economy of thought » .
>
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Re: [time-nuts] Oscilloquartz 8600-3 Disassembly pictures...

[Didier Juges]

You are always welcome to upload time-nuts related material to my manual
site www.ko4bb.com

Didier KO4BB

On Dec 14, 2017 1:03 AM, "Ulf Kylenfall via time-nuts" 
wrote:

>
> Tried to mail the pictures to Magnus. The mail bounced back.
> Ole Petter Ronningen was kind to also offer space for themand they can be
> found at:
>
> www (dot) efos3 (dot) com/osa8600-3
>
> 73
> Ulf Kylenfall - SM6GXV
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Re: [time-nuts] Weird GPSDO behavior

[Didier Juges]

Where I work, we had a high power system tripping and occasionally blowing
up at 7:00 AM. It turned out that it was when the power company switched
big capacitors across the lines as businesses got started to keep the power
factor within their target range. It was creating just the kind of
transient that drove the controller loop of the power factor corrector in
our power supply to go bezerk (62kW converter running off 480VAC 3 phase).
The system had been tested to MIL-STD-704 transients and passed, but that
capacitor switching just killed it.

On Sep 29, 2017 8:15 AM, "Rob Kimberley" 
wrote:

> I'd go with a power surge as it's so regular at 8AM.
> Rob
>
> -Original Message-
> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Skip
> Withrow
> Sent: 28 September 2017 21:18
> To: time-nuts
> Subject: [time-nuts] Weird GPSDO behavior
>
> Hello Time-Nuts,
>
> I have a NTGS50AA GPSDO (close cousin to the NTBW50AA and Thunderbolt)
> with the OCXO removed and a SRS PRS-10 rubidium oscillator in its place.  I
> have been running Lady Heather 5.0 and have changed the damping, gain, and
> time constant to give me a 20,000 second time constant with a damping of
> .6.  I have attached a Lady Heather screen shot of the weird behavior.  You
> can see that my GPS antenna is in a very none ideal location (window on the
> west side of the building).
>
> Once per day (about 8am) something disturbs the system.  So, the GPSDO
> spends much of its time recovering and never gives me anywhere near the
> performance that this system is capable of.  I would think that it is not
> the PRS-10 as it has no knowledge of time.  I would also think that it is
> not the GPS system or receiver, since the GPS constellation repeats twice
> per day.
>
> Kind of the two things that I am left with are a glitch by the power
> company every morning (there is some large industrial machinery across the
> street (but then I would kind of expect glitches at 8am and 5pm), and
> perhaps Lady Heather doing something funny.  This system has been running
> for quite some time, I have not tried restarting Lady Heather yet.
>
> Anybody seen anything like this, or have any good ideas?
>
> Thanks in advance,
> Skip Withrow  style="border-top: 1px solid #D3D4DE;">
> 
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>
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Re: [time-nuts] Weird GPSDO behavior

[Didier Juges]

It makes me feel better (not good, just better) to know it's not just me...

On Sep 29, 2017 7:19 AM, "Bob kb8tq"  wrote:

> Hi
>
>
> > On Sep 28, 2017, at 6:59 PM, Mark Sims  wrote:
> >
> > I suspect that it is either temperature related (the funkiness starts
> around when the temperature reaches a minimum) or related to the way the
> disciplining parameters are hacked to get the extended time constant.
>
> Like it or not, most of these devices were made back a while ago.
> The CPU’s used were not the ones we have today. the code was tested
> over the “expected range” of values. Most (but not all) of the control loop
> code was done as integer math. With limited RAM, tossing everything into
> 64 or 128 bit integers was not an option. In some cases 32 bit int’s were
> at
> a premium. Multiply this by that, that, and that. Then divide by
> something, and
> something else. … hmmm…. a few bits just went missing. Could you reorder
> and fiddle to fix some of this? Sure, that’s where we get back to the
> expected
> range stuff.
>
> Even if it’s not in the “main loop”, GPSDO code is full of checks for this
> or that.
> Like the main math, they are scaled and tested for the normal range of
> parameters.
> Not all of them spurt error messages when they get involved. Some just
> bump this
> or that and move on.
>
> Lots of possibilities ….
>
> Bob
>
>
>
> > Try setting up for say a 10,000 second time constant and see how things
> change.
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[time-nuts] KO4BB Manual Pages

[Didier Juges]

News flash!

If you have been using my site to upload and download manuals, you may have
noticed that in the last year or so I had become fairly slow at checking
new uploads and moving them to the general area so that they can be
downloaded.

The reasons were multiple and I want to take this opportunity to apologize
to you. Just because this service is free is not an excuse to make it hard
to use or inconvenient.

The good news is that I do have a new tool now that allows me to check and
move the uploaded manuals to their respective folders conveniently.

More improvements are planned to the upload log (letting you know what the
file name was changed to and where it was moved), these will come later.

This primarily applies to documents in PDF or image (GIF, JPG, PNG) format
that I can easily preview. DOC, ZIP or RAR files unfortunately still
require more manual intervention, so they will not benefit from this
improvement, but since I will spend less time processing the PDF files,
which are the vast majority of the files that are uploaded, I will have
more time available for the rest.

I remind you that files that are in the Upload folder are readily
accessible via ftp, so if you need one or more files that are in the Upload
folder and that I have not moved yet, fire up your ftp client (info is on
the Manuals page).

Thank you for your patience and patronage.

Didier KO4BB
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Re: [time-nuts] Thunderbolt question

[Didier Juges]

"If the Thunderbolt loses satellites, does it still put out a 10 Mhz
signal?"

Yes of course. When that happens, the Thunderbolt is said to be in holdover.

On Aug 3, 2017 9:29 PM, "Chris Waldrup"  wrote:

> Hi,
>
> I just noticed the laptop that is always connected to my Thunderbolt had a
> yellow block under COM1 on the Tboltmon program where it normally is green.
> Also the date up on the screen was in early July. Satellites were still
> shown.
> The counter I leave connected still shows a 10 Mhz output.
> I reset the program and this time all fields are ??? and com not detected.
> I had thought maybe the laptop hung up.
> I'll look at my system tomorrow. I'm trying to do a divide and conquer. If
> the Thunderbolt loses satellites, does it still put out a 10 Mhz signal?
>
> Thank you.
>
> Chris
> KD4PBJ
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Re: [time-nuts] Thunderbolt - trouble locking with some types of antennas

[Didier Juges]

" having around 20 dB of gain at the antenna greatly decreases the effect
of feed line loss on noise figure."

And that would be consistent with usage for a timing receiver which is
expected to have a well exposed antenna and a significant line length, as
opposed to navigation receivers where the antenna is expected to have a
short feed line.

On Mon, Jul 31, 2017 at 4:17 PM, Brooke Clarke  wrote:

> Hi Jerry:
>
> The Trimble is the oldest mass produced GPS receiver I know of and because
> the early receivers used high gain antennas it seems that Trimble kept that
> idea for the newer designs. They like about 41 dB gain between the antenna
> and the input to the receiver.
> http://www.prc68.com/I/Trimpack.shtml#Ant
> Newer designs probably place that gain in the front end rather than at the
> antenna.  But having around 20 dB of gain at the antenna gretly decreases
> the effect of feed line loss on noise figure.
>
> --
> Have Fun,
>
> Brooke Clarke
> http://www.PRC68.com
> http://www.end2partygovernment.com/2012Issues.html
>
>
>  Original Message 
>
>> Due to access problems, I run my Thunderbolt with a Symmetricom 58532A
>> antenna placed indoor near a window facing South… can’t get much worse but
>> most of the time it will be locked onto 3 or 4 satellites.I recently
>> bought a www.leobodnar.com   GPSDO for my SDR
>> ham
>> radio setup.  I was very surprised to find that this minimalist GPSDO
>> using
>> a small patch antenna with internal LNA placed near my window had
>> satellite
>> & PPL lock within a few seconds.  It requires 3-4 satellite locks for its
>> PPL.  However, when I attached the patch antenna to my Thunderbolt –
>> satellite signal strength were zero or minus for all satellites.  The
>> specs
>> for the patch antenna are listed below.
>>
>>
>> I would appreciate any advice understanding this behavior.
>>
>>
>> Jerry NY2KW
>>
>>
>> Center Frequency 1575.42MHz±3 MHz
>>
>> V.S.W.R 1.5:1
>>
>> Band Width ±5 MHz
>>
>> Impendence 50 ohm
>>
>> Peak Gain >3dBic Based on 7×7cm ground plane
>>
>> Gain Coverage >-4dBic at –90°<0<+90°(over 75% Volume)
>>
>> Polarization RHCP
>>
>> LNA/Filter
>>
>> LNA Gain (Without cable) 28+/-3dB
>>
>> Noise Figure 1.5dB Typ.
>>
>> Filter Out Band Attenuation (f° =1575.42MHz)
>>
>> 7dB Min f0+/-20MHZ
>>
>> 20dB Min f0+/-50MHZ
>>
>> 30dB Min f0+/-100MHZ
>>
>> V.S.W.R <2.0
>>
>> DC Voltage 2.7V/3.0V/3.3V/5.0V/3.0V to 5.0V/other
>>
>> DC Current 5mA /11mA/15mA Max
>>
>>
>>
>>
>> ___
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>> ailman/listinfo/time-nuts
>> and follow the instructions there.
>>
>>
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Re: [time-nuts] Thunderbolt - trouble locking with some types of antennas

[Didier Juges]

"The newer the receiver, the more horsepower in the silicon. In the case of
GPS, that
gives you more correlators to do DSP. The sensitivity improvement is a
direct result
of that. If you take a look at the guts of a TBolt, they date to the late
1990’s. That’s
a long time in silicon years …."

It seems that more correlators would speed up the time to first fix, not
necessarily the sensitivity, particularly I do not see how it would
directly affect the capability to stay locked when signal strength
fluctuates?
On the other hand, more correlators may help when there is multipath and a
whole bunch of extraneous signals are fed into the receiver, so maybe the
apparent lack of sensitivity is really the inability to see the signal from
the chaff, not necessarily sensitivity in terms of noise figure.


On Mon, Jul 31, 2017 at 3:06 PM, Bob kb8tq <kb...@n1k.org> wrote:

> Hi
>
> > On Jul 31, 2017, at 3:32 PM, Didier Juges <shali...@gmail.com> wrote:
> >
> > The Thunderbolt is well known for not having the best sensitivity among
> GPS
> > receivers. It seems that timing receivers in general, particularly those
> of
> > the same generation as the Thunderbolt are not as sensitive as navigation
> > (possibly newer) GPS receivers. It may be because they are expected to
> run
> > with amplified antennas?
>
> The newer the receiver, the more horsepower in the silicon. In the case of
> GPS, that
> gives you more correlators to do DSP. The sensitivity improvement is a
> direct result
> of that. If you take a look at the guts of a TBolt, they date to the late
> 1990’s. That’s
> a long time in silicon years ….
>
> Bob
>
>
> >
> > Based on the spec you wrote, it looks like your antenna has no gain, so
> > definitely I would expect less than good performance.
> >
> > My 3 Thunderbolts have been running with inside antennas (2 pucks and one
> > Trimble Bullet) but my ham shack is upstairs and other than the ceiling
> and
> > the shingle roof, there are no other obstructions and they are doing OK
> not
> > great (all 3 go on holdover somewhat regularly). I am now running one
> > downstairs (while I work on the new software for the TB Monitor) with 50
> > feet of RG-58 going to a HP 58532A antenna somewhat in the clear but
> only 8
> > feet above ground with significant obstructions in pretty much all
> > directions due to the low height and the Thunderbolt is happy as a clam
> in
> > spite of the significant losses in the cable. The HP antenna works much
> > better than the Trimble Bullet antenna.
> >
> > On Mon, Jul 31, 2017 at 12:19 PM, Jerry <jster...@att.net> wrote:
> >
> >> Due to access problems, I run my Thunderbolt with a Symmetricom 58532A
> >> antenna placed indoor near a window facing South… can’t get much worse
> but
> >> most of the time it will be locked onto 3 or 4 satellites.I recently
> >> bought a www.leobodnar.com <http://www.leobodnar.com>  GPSDO for my SDR
> >> ham
> >> radio setup.  I was very surprised to find that this minimalist GPSDO
> using
> >> a small patch antenna with internal LNA placed near my window had
> satellite
> >> & PPL lock within a few seconds.  It requires 3-4 satellite locks for
> its
> >> PPL.  However, when I attached the patch antenna to my Thunderbolt –
> >> satellite signal strength were zero or minus for all satellites.  The
> specs
> >> for the patch antenna are listed below.
> >>
> >>
> >>
> >> I would appreciate any advice understanding this behavior.
> >>
> >>
> >>
> >> Jerry NY2KW
> >>
> >>
> >>
> >> Center Frequency 1575.42MHz±3 MHz
> >>
> >> V.S.W.R 1.5:1
> >>
> >> Band Width ±5 MHz
> >>
> >> Impendence 50 ohm
> >>
> >> Peak Gain >3dBic Based on 7×7cm ground plane
> >>
> >> Gain Coverage >-4dBic at –90°<0<+90°(over 75% Volume)
> >>
> >> Polarization RHCP
> >>
> >> LNA/Filter
> >>
> >> LNA Gain (Without cable) 28+/-3dB
> >>
> >> Noise Figure 1.5dB Typ.
> >>
> >> Filter Out Band Attenuation (f° =1575.42MHz)
> >>
> >> 7dB Min f0+/-20MHZ
> >>
> >> 20dB Min f0+/-50MHZ
> >>
> >> 30dB Min f0+/-100MHZ
> >>
> >> V.S.W.R <2.0
> >>
> >> DC Voltage 2.7V/3.0V/3.3V/5.0V/3.0V to 5.0V/other
> >>
> >> DC Current 5mA /11mA/15mA Max
> >>
> >>
> >>
> >>
> >>
> >>
> >>
&

Re: [time-nuts] Thunderbolt - trouble locking with some types of antennas

[Didier Juges]

The Thunderbolt is well known for not having the best sensitivity among GPS
receivers. It seems that timing receivers in general, particularly those of
the same generation as the Thunderbolt are not as sensitive as navigation
(possibly newer) GPS receivers. It may be because they are expected to run
with amplified antennas?

Based on the spec you wrote, it looks like your antenna has no gain, so
definitely I would expect less than good performance.

My 3 Thunderbolts have been running with inside antennas (2 pucks and one
Trimble Bullet) but my ham shack is upstairs and other than the ceiling and
the shingle roof, there are no other obstructions and they are doing OK not
great (all 3 go on holdover somewhat regularly). I am now running one
downstairs (while I work on the new software for the TB Monitor) with 50
feet of RG-58 going to a HP 58532A antenna somewhat in the clear but only 8
feet above ground with significant obstructions in pretty much all
directions due to the low height and the Thunderbolt is happy as a clam in
spite of the significant losses in the cable. The HP antenna works much
better than the Trimble Bullet antenna.

On Mon, Jul 31, 2017 at 12:19 PM, Jerry  wrote:

> Due to access problems, I run my Thunderbolt with a Symmetricom 58532A
> antenna placed indoor near a window facing South… can’t get much worse but
> most of the time it will be locked onto 3 or 4 satellites.I recently
> bought a www.leobodnar.com   GPSDO for my SDR
> ham
> radio setup.  I was very surprised to find that this minimalist GPSDO using
> a small patch antenna with internal LNA placed near my window had satellite
> & PPL lock within a few seconds.  It requires 3-4 satellite locks for its
> PPL.  However, when I attached the patch antenna to my Thunderbolt –
> satellite signal strength were zero or minus for all satellites.  The specs
> for the patch antenna are listed below.
>
>
>
> I would appreciate any advice understanding this behavior.
>
>
>
> Jerry NY2KW
>
>
>
> Center Frequency 1575.42MHz±3 MHz
>
> V.S.W.R 1.5:1
>
> Band Width ±5 MHz
>
> Impendence 50 ohm
>
> Peak Gain >3dBic Based on 7×7cm ground plane
>
> Gain Coverage >-4dBic at –90°<0<+90°(over 75% Volume)
>
> Polarization RHCP
>
> LNA/Filter
>
> LNA Gain (Without cable) 28+/-3dB
>
> Noise Figure 1.5dB Typ.
>
> Filter Out Band Attenuation (f° =1575.42MHz)
>
> 7dB Min f0+/-20MHZ
>
> 20dB Min f0+/-50MHZ
>
> 30dB Min f0+/-100MHZ
>
> V.S.W.R <2.0
>
> DC Voltage 2.7V/3.0V/3.3V/5.0V/3.0V to 5.0V/other
>
> DC Current 5mA /11mA/15mA Max
>
>
>
>
>
>
>
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> To unsubscribe, go to https://www.febo.com/cgi-bin/
> mailman/listinfo/time-nuts
> and follow the instructions there.
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Re: [time-nuts] A look inside the DS3231

[Didier Juges]

That device also has analog circuitry for the oscillator itself and the
temperature sensor and the temperature compensation.
I believe I have read an app note some time ago, it may have been from
Maxim describing a kind of ring oscillator being used as a temperature
sensor which drew much less power than a bandgap or a PN junction and
directly produced a digital output.
The DAC itself, or whatever circuit they use for temp compensation also has
analog components and must use pico power.
Quite amazing.

On Jul 30, 2017 7:13 AM, "Attila Kinali"  wrote:

> On Sun, 30 Jul 2017 12:23:17 +0200
> Pete Stephenson  wrote:
>
> > > > - I find it remarkable that this circuit can operate on less than a
> > > > microamp during normal usage, including temperature conversion.
> > >
> > > That's not so remarkable. If you make the transistors long, then
> > > you get very low leakage. Couple that with small clock frequency
> > > and you use very little current. Modern ICs only use so much current
> > > because they have so many transistors, which are also optimized
> > > for being fast, rather then low leakage.
> >
> > Good point! I admit the details of optimizing transistors for different
> > purposes is beyond my ken, and I appreciate the insight.
>
>
> There are multiple optimization points. One is to select a prodcution
> process that is optimized for low leakage. I.e. thick gate oxide
> and high threshold voltage. Both of these parameters imply higher
> suplly voltage.
> Then, in the design, you make your transistors long and large.
>
> The problem here is, that power consumption scales proportional
> to the square of supply voltage, the gate capacitance and the
> switching frequency. This means, if you choose a low leakage
> process, and thus high supply voltage, your power consumtion
> will go up. The same goes for choosing large transistors.
> Hence it becomes a trade-off between static (leakage) and
> dynamic (through gate capacitance) power consumption.
>
>
> > > > The DS3231 has on-board temperature monitoring to correct the crystal
> > > > frequency: is this something where they would have bothered putting a
> > > > separate sensor next to the crystal itself, or are the die and the
> > > > crystal are close enough and in the same package that they could use
> an
> > > > on-die sensor like a diode and call that "good enough"?
> > >
> > > My guess would be that it's a PN-junction or a bandgap temperature
> > > sensor somewhere on the chip. Adding another part increases the cost
> > > of production quite considerably.
> >
> > Indeed. At first glance, I was surprised not to see tiny discrete
> > capacitors within the chip package itself, as I assumed (incorrectly)
> > that getting sufficient capacitance to steer a crystal a little would
> > require larger capacitors than could be easily put on a die, but then I
> > remembered that each LSB in the aging register only changes the
> > frequency by 0.1ppm at 25C, so that wouldn't need a large amount of
> > capacitance.
>
> As a rule of thumb, you can assume that in an "old" (aka large node size)
> process the gate capacitance is approximately 1nF per mm^2. So, you can
> build quite easily 10-100pF of capacitors on-chip.
>
>
> Attila Kinali
> --
> You know, the very powerful and the very stupid have one thing in common.
> They don't alters their views to fit the facts, they alter the facts to
> fit the views, which can be uncomfortable if you happen to be one of the
> facts that needs altering.  -- The Doctor
> ___
> time-nuts mailing list -- time-nuts@febo.com
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>
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Re: [time-nuts] Trimble Thunderbolt no longer determines the correct date

[Didier Juges]

Since the Thunderbolt is hard coded to detect a particular week to
determine if it should add 1024 to the week number, I would guess that each
product has a magic date based on the anticipated release date of the
product (week 936 for the Thunderbolt), and it will work for 1024 weeks
from that date.

I cannot imagine a work around since the problem stems from the GPS service
only identifying the current date within a particular 1024 weeks epoch
unless the government changes the amount of data that is sent over the GPS
system. Somebody has to use other method to determine the epoch and add the
corresponding offset.



On Thu, Jul 27, 2017 at 12:36 PM, Keith Loiselle 
wrote:

> Hi,
>
> It came to our attention at Jackson Labs that the Trimble Thunderbolt will
> fail to start with the correct date after July 30, 2017.   See the clip
> from the Thunderbolt manual below.
>
> Does anyone have any updates from Trimble regarding fixes for this
> problem?  Does does this affect other Trimble products (i.e. Mini-T,
> Resolution T) in the same way?
>
> [image: Inline image 1]
>
> Please note that Jackson Labs products are not affected by the up-coming
> April 2019 GPS week roll over, and can determine the correct date until the
> following dates:
>
>
>
>uBlox-8 based products - 4/24/2033
>
>uBlox-6 based products - 5/12/2030
>
>Legacy uBlox-5 based products - 12/3/2028
>
> Thanks,
> Keith
>
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Re: [time-nuts] 5370B Input Board Repair [WAS: 5370B Question / help needed]

[Didier Juges]

That is very good information. I will add your email to the 5370 page on my
web site.

Didier KO4BB


On Jul 18, 2017 4:02 AM, "Thomas Allgeier"  wrote:

> Hello All Again,
>
>
>
> I’ve got my 5370B going now and in the process made a “discovery” which I
> thought might be worth sharing:
>
> The A3 input board is a through-hole PCB with a few SMD capacitors and
> resistors on the reverse of the “switch area”. It turns out that on my 5370
> (2410A00777) these components are not soldered, but fitted with conductive
> adhesive. I first thought it was solder with a black coating but under a
> microscope it is clear that it is not solder at all. Most probably it is a
> mixture of epoxy and silver particles, or a similar compound. So no going
> over joints with a fine iron…
>
> Inspecting all this carefully under the microscope I discovered that the
> “joints” on 2 resistors (R23 and R56) had cracked. As you know this board
> gets heat from the hybrid amplifier IC’s and due to the way the board is
> mounted to the front panel I guess it sees thermal stressing when the
> instrument warms up and cools down. While this obviously lasts a long time
> it looks that on my unit the adhesive has eventually cracked in places.
> (Vigorous switch activation and pressing / pulling on the switch handles
> also won’t be helpful in this respect…) One of the resistors just fell off
> at the slightest touch with fine tweezers.
>
>
>
> Anyhow, after removing the offending components, cleaning the pads of the
> adhesive, and soldering replacements in place, we have a perfect 99.9x ns
> with the 10 MHz on the commoned inputs. Happy days!
>
>
>
> So if any of your 5370’s have the kind of intermittent fault I described
> (and one or two other people seem to have reported) or instability that
> seems to originate from the A3 board – check the joints around the SMD’s.
>
>
>
> I wonder why / how it ended up having the adhesive instead of solder –
> were earlier / later instruments the same, or was this a build change
> introduced at a certain period?
>
>
>
> Hope the above is of help to somebody else,
>
> Thomas.
>
>
>
> Message: 1
> Date: Sat, 15 Jul 2017 21:54:47 +0100
> From: Thomas Allgeier 
> To: Discussion of precise time and frequency measurement
> 
> Subject: Re: [time-nuts] 5370B Question / help needed
> Message-ID:
> 

Re: [time-nuts] Power connectors continued

[Didier Juges]

I have been forced to use micro-D by a customer on a military power supply,
not even space rated, it was well over $100 each in 50 piece quantity (I
think it was a 25 pin).

However, unless they are mistreated (which is easy for the reason you
listed), they seem reliable. I do not believe we have replaced one in over
400 units shipped and a 15 year period (aside from a couple of prototypes
that went through hell). That must be one of our better customers...

The design choice of protecting the pin instead of the socket is baffling.


On Jun 23, 2017 7:03 PM, "jimlux"  wrote:

On 6/22/17 4:22 PM, William H. Fite wrote:

> A good friend of mine, sadly of blessed memory, was a lead engineer for
> Grumman on the comm systems of the lunar lander. He spoke of small
> space-rated multi-pin connectors that cost upward of $500 each.
>
>
> The Micro-D is widely used in spaceflight, and is a pox on the connector
world - not only are they expensive, the way the pins and jacks are made is
almost asking for damage - the pin is shrouded in a hole, and the jack is
exposed. $100 for a 9 pin wouldn't surprise me.

Lately, I've been encountering nano-D (Glenair, Omnetics) - they're not as
delicate, they're smaller.






> On Thursday, June 22, 2017, Arnold Tibus  wrote:
>
>
>> Hello,
>>
>> I can second Magnus and want to throw in some more details.
>> Cannon, Deutsch, Bendix, Souriau, Matrix, Amphenol,  etc. etc. are (big)
>> companies manufacturing all kind of connectors and are  n o t  connector
>> type designations! Important are the type numbers of the manufacturer or
>> higher level specification numbers.
>> We used in the aircraft and spacecraft business naturally the military
>> (MS-) numbers listed in the MIL-QPL (or eg. for Spacelab with GSFC spec.
>> no). Most types of connectors are under these numbers available from
>> different manufacturers, of course with different manufacturer in house
>> part numbers. Attention: the 'same' connectors may be bought w/o the
>> Mil.-spec. sheets with somewhat lesser quality. Important details are
>> the max. mating number, the contact resistance (e.g. 20 mOhm) and the
>> max. continuous current, max. Voltage, vibration resistance and
>> reliability etc.  Of course, this makes good connectors somewhat
>> 'expensive'. Hirel and non-magnetic gold plated D- subminiture type
>> connectors do survive e.g. the rocket launch phase (high vibrations),
>> vacuum and low temperatures and are still used for space projects.
>>
>

AMP (and others) sell a lower cost version called the "Circular Plastic
Connector" or CPC. A coarser screw thread than the round metal MS
connectors.

The round connectors (called Bendix connectors by some at JPL, because, of
course, that was the mfr for some batch of them) have a nice mil-std to
define them.  There's a Shell, an Insert, and pins/jacks.  You can get
shells and inserts with different keys and "clocking" to prevent mismates.
There are coax and triax inserts, high voltage inserts, etc.

While they're pricey brand new, there are numerous surplus suppliers (Apex
Electronics in Sun Valley, CA used to have thousands of them).

You can get them hermetic, vacuum tight, waterproof, locking, non-locking,
every kind dielectric imaginable, etc.







>>  The D-sub series of connectors was introduced by Cannon in 1952. They
>> are still available as standard, hirel, and non-magnetic versions. The
>> contacts were machined contacts forcrimping or soldering connection and
>> made of massive copper with gold finish. (more see e.g.
>> https://en.wikipedia.org/wiki/D-subminiature). Example for the standard
>> 9 pin connector designation (crimp): DEMAM-9S and DEMAM-9P. Today are a
>> big number of companies producing equivalent types. Cheap ones are
>> equipped with contacts made of sheetmetal. Nobody should expect then the
>> same spec. values as reliability, mating numbers, contact power rating
>> etc.
>> It is up to the designer of a product to be informed and select the
>> right quality device for his product ...
>>
>

My problem with D-sub is two fold:
1) making a chassis hole is a pain - although now, with places like Front
Panel Express, it's less so.
2) the shroud around the plug/male gender is easy to bend if it gets
stepped on.  Sure, for flight hardware, carefully handled under the
watchful eye of QA, not an issue, but I have lots of these from my
not-entirely-mis-spent youth that are bent.

They do come with removable pins/jacks, and you can get coax flavors too.
They're fairly compact in a panel.


Other connectors of interest are those made by Lemo and Hirose.  Lemo are
locking, pretty rugged when mated, and small for the number of conductors.
You see them on high end video and medical gear.

There's also something about double banana plugs and mating jacks. I go
back and forth between PP and banana plugs for preference.

BTW, there are panel mounts for PP.





___

Re: [time-nuts] GPS Antenna on Tower.

[Didier Juges]

If that is not time-nutty, I do not know what will :)

On Jun 20, 2017 7:04 AM, "jimlux"  wrote:

>
> for geodetic measurements, they drill a hole down to bedrock, and run a
> pipe down to anchor the antenna to the bedrock.
>
> "All holes shall be drilled straight enough so that PVC casing can be
> installed in the top 15.5 ft of each hole, and that the steel pipe can be
> freely lowered, not forced, for its entire 35 ft length."
>
> http://kb.unavco.org/kb/article/deep-drilled-braced-monument
> -overview-300.html
> http://www.scign.org/arch/sdb_monument.htm
>
>
> Google for Ken Hudnutt's or Frank Webb's papers
>
>
> or a 3m tall monument for a CORS station
>
> http://www.mwrtk.net/support_docs/corsinstallprocedures.pdf
>
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Re: [time-nuts] backfill (was: Poor man's oven)

[Didier Juges]

The difficulty with hydrogen is to keep it where you want it. It does not
take very much for it to leak out (or in, as the case may be)

On Jun 8, 2017 4:58 PM, "Alan Melia"  wrote:

> Hi Bob, it also depends on what you allow to leak into the vacuum.
> Hydrogen is a pretty effective remover of heat :-))
> Alan
> G3NYK
>
> - Original Message - From: "Bob kb8tq" 
> To: "Discussion of precise time and frequency measurement" <
> time-nuts@febo.com>
> Sent: Thursday, June 08, 2017 9:19 PM
> Subject: Re: [time-nuts] backfill (was: Poor man's oven)
>
>
> Hi
>>
>> If you look at the thermal conductivity vs very low pressures, the
>> conductivity
>> comes up pretty quickly from a hard vacuum. There is essentially no impact
>> on Q.
>>
>> Bob
>>
>> On Jun 8, 2017, at 4:03 PM, Attila Kinali  wrote:
>>>
>>> On Thu, 8 Jun 2017 06:55:07 -0400
>>> Bob kb8tq  wrote:
>>>
>>> The simple answer is that the backfill is done because it does matter in
 a lot of
 cases.

>>>
>>> This raises the question, why there is backfill (just for thermal
>>> conductivity?)
>>> and how much it affects the Q of the crystal.
>>>
>>> Attila Kinali
>>>
>>>
>>> --
>>> You know, the very powerful and the very stupid have one thing in common.
>>> They don't alters their views to fit the facts, they alter the facts to
>>> fit the views, which can be uncomfortable if you happen to be one of the
>>> facts that needs altering.  -- The Doctor
>>> ___
>>> time-nuts mailing list -- time-nuts@febo.com
>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m
>>> ailman/listinfo/time-nuts
>>> and follow the instructions there.
>>>
>>
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>>
>
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Re: [time-nuts] uC ADC resolution (was: Poor man's oven)

[Didier Juges]

The good news is that for oven control, you can typically filter the heck
out of the data and the noise may actually help you with dithering if it's
fairly random, so you should be able to get close to the specs. The main
thing you need is stability, linearity should not be a factor. One
limitation will be the built in reference so unless you can switch to an
external reference, that may be the main issue.

I have been using the Silabs line of 8051 uCs and I found their ADCs
handily meeting their specs, at least on the devices I have tried (I have
used up to 12 bit ADC on their parts).

I also have used the MSC1210 (from originally Burr Brown, now TI). The only
board that came close to the 24 bit advertised performance of their ADC was
the demo board from Burr Brown themselves, and it was very slow. Anything
that I designed with it (with their help and advice) never got anywhere
near that and I gave up on that chip.

Didier KO4BB

On Jun 6, 2017 4:17 PM, "Attila Kinali"  wrote:

On Tue, 6 Jun 2017 16:37:27 -0400
Bob kb8tq  wrote:

> Often when you dig into the details of MCU ADC’s they have a little note
“optimized for audio” or
> “not recommended for control loops”. It can be a bit of a head scratcher
to work out what they are
> getting at. The big issues in this case seem to be DC leakage and 1/F
noise. Yes, they do sort of go hand in hand :)
> You need to be willing to check out the ENOB at DC in order to use them
effectively in a simple
> OCXO setup. That or be willing to flip the bridge ends on demand and try
to cancel out the issues.
> Unfortunately that adds both complexity and a string of other fun and
games.

uC ADCs are only good for low resolution, slow signals. For anything else
you need an external ADC. Even if your uC datasheet claims that you have
a 12bit ADC, the reality is quite different. For one, these ADCs are not
well specified, the surounding digital logic has a profound effect that
changes dramatically depending on what other periphery you use or not.

You can always just subtract two bits of the ADCs resolution and you
wouldn't be wrong. Losing 3 bits to internal noise isn't unehard of
either. Heck, the STM32F4xx have so much internal noise that the ENOB
of their ADC is below 6bit... so low that they even had to write an
appnote on how to do averaging to get back to the 12 bits the ADC is
spec'ed for. (but don't mention that to an ST sales person, they will
hate your guts afterwards).

Rule of thumb: If you need your ADC DC stable, more than 8bit resolution,
or more than 10-1000 samples per second: use an external ADC.

Attila Kinali

--
You know, the very powerful and the very stupid have one thing in common.
They don't alters their views to fit the facts, they alter the facts to
fit the views, which can be uncomfortable if you happen to be one of the
facts that needs altering.  -- The Doctor
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Re: [time-nuts] Line Frequency standard change - Possible ?

[Didier Juges]

One issue with power factor corrected power supplies is that in the short
term (as a minimum, at the line frequency), they do behave like resistors
(current goes up when voltage goes up) but as they have a slow voltage
regulation loop to provide regulated output, they do behave like constant
power loads to the grid in the long term. The transition between the two
modes of operation is not always smooth and can lead to instabilities when
combined with the generator's response and the line impedance.
I had this particular problem with a 5kW PFC corrected power supply that
was working fine by itself but caused line oscillations when 16 of them
were running in parallel.

On Feb 11, 2017 4:04 AM, "David"  wrote:

> On Thu, 9 Feb 2017 19:06:51 -0500, you wrote:
>
> >One simplistic way to look at all this is that a switcher presents a
> “negative
> >resistance” load. If you drop voltage, current goes up. OCXO’s happen
> >to share this issue. Negative resistances are *not* what most power source
> >guys want in their control loop.
> >
> >Bob
>
> People working with emitter/source followers do not like it either and
> I cannot see the folks using inverters wanting to pay to put big
> resistive heaters across the grid to compensate.
>
> Adding power factor correction to switching power supplies was cheap
> compared adding "negative resistance" correction.
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Re: [time-nuts] Dropbox is cool, but...

[Didier Juges]

Yes, I noticed that before.
I have a number of tools that don't like running off a Dropbox folder,
including several software development tools for starter. Too many files
opened at the same time.
Don't assume that because it looks like a normal folder, it works like one,
even though for many things, it does work remarkably well.

On Feb 5, 2017 2:32 PM, "John Ackermann N8UR"  wrote:

> So I was clever and decided to log some PPS data to a folder within my
> "Dropbox" folder.  Strange results followed... the whole system just bogged
> down, and even fairly slow serial data dropped characters.
>
> It turns out that the culprit was the Dropbox daemon continuously trying
> to sync the file as it changed every second.  It didn't manifest as CPU
> overload or anything obvious; the problem was apparently thrashing in the
> I/O system.  Once I started dumping the data to a "normal" directory, the
> problem went away.  (This was on Linux, by the way).
>
> So, a lesson learned -- don't stream unbuffered data, even at a low rate,
> into a sync'd folder!
>
> John
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Re: [time-nuts] Li-ion Battreries

[Didier Juges]

Well worth mentioning that you have found a reputable vendor. I may give
them a try.

A while back, I bought a dozen 18650 inexpensive(<$5 each) cells from 3
vendors picked at semi-random on eBay (4 from each) for evaluation and I
tested each one of them with a data logger.
The best one had about half the advertised capacity, the others went down
from there. Important to observe that none of the set I bought were even
remotely matched, a crucial consideration if you are going to put them in
series (a balancer will only ensure your pack is no better than the worst
cell in the pack).
Many of the 18650 cells you find on eBay (and maybe other places) are
actually coming from old laptop battery packs that normally should have
been discarded/recycled.

In my anticipated application, I only needed one cell (to be followed by a
small boost converter), so the issue of balance and matched set was not
important, but simply I needed the capacity and none were remotely
satisfactory. I ended up using cell phone booster packs, since I needed 5V
anyway.


On Sun, Jan 22, 2017 at 9:44 AM, Bert Kehren via time-nuts <
time-nuts@febo.com> wrote:

> I use 4 cell balancing and protection circuits, cost a couple of $ more but
>  well worth it, I use holders because of  limited availability of cells
> with  straps, but rest assured they are held down (discarded PCB)'s,
> I on purpose did not get into technical details I was only trying to share
> reliable sources, based on disappointing past experiences.
> Bert Kehren
>
>
> In a message dated 1/22/2017 10:00:45 A.M. Eastern Standard Time,
> att...@kinali.ch writes:
>
> Hoi  Bert,
>
> On Sat, 21 Jan 2017 08:08:22 -0500
> Bert Kehren via time-nuts   wrote:
>
> > purchased  _2x   Samsung 35E 3500mAh 10A 18650 High Drain Rechargeable
> Battery
> >  INR18650-35E_
> >
> (http://www.ebay.com/itm/112173495496?_trksid=p2060353.
> m2749.l2649=STRK:MEBIDX:IT)   for two reason 10 A load  and
> good price. These
> > cells have no  protection, which I want, since I will for  our
> applications
> > stack 4 with a 4  cell controller and in two application also  parallel
> cells
> > for a total of  8.  I have now completed my  tests  and concentrate my
> > battery work on using these   cells.
> > After having tested 26650 cells with disappointing   results my focus is
> on
> > 18650. I am sure there will be 26650 cells  available, but  right now our
> > focus is on 18650.
> > I have  no connection in any way with these two sources,  but think it
> may
> > be helpful for those that look for batteris and do not want to   go
> through
> > the process I went through.
>
>
> Some  small remarks: 18650 is by far the most common form factor
> of Li-Ion  batteries on the market. This is IMHO the better choice
> than the 26650 if  you want to be able to replace them in 10-20 years.
>
> If you stack Li-*  batteries, you will need to have a controller that
> monitors each cell  individually while charging or has some other means
> of ensuring that none  of the cells are overcharged (or rather that they
> are charged the same  amount). This kind of circuit is called balancer.
> A protection circuit does  _not_ replace a balancer. The protection circuit
> is only to protect against  catastrophic failure. Ie it is still possible
> to overcharge a battery even  if it has a protection circuit. You also do
> not know what the protection  circuit does to protect the cell. There are
> a lot of chips out there, that  simply open a switch and thus disconnect
> the cell. In this case, the  protection circuit of one cell will disconnect
> the whole stack and break  charging.
>
> A lot of the multi-cell Li-Ion charger chips have integrated  cell
> protection
> circuitry. Ie if you use one of them, you will not need an  additional
> protection circuit. But be aware, the regulation for battery  protection
> circuit states that the circuit has to be wired fix onto the  battery
> in a way that this connection cannot be broken (without breaking  the
> housing of the battery pack). The reason for this is, i think,  pretty
> obvious. I would recommend that you solder each cell  indidividually
> into your circuit instead of using some kind of holder. Or  if you are
> using a holder, make it such that there is no chance any of the  cells
> can be accidentally short circuited.
>
> Attila Kinali
> --
> Malek's Law:
> Any simple idea will be worded in the most complicated  way.
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Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

[Didier Juges]

I use Copper Connection, a $50 package (PWB layout only) that works very
well for me.
There is a free eval version that has some limitations.

Didier KO4BB


On Jan 19, 2017 11:01 PM, "Richard (Rick) Karlquist" 
wrote:

> Off topic, but probably a lot of disgrunted Eagle users on this list.
> Its official, you will now have to pay $500 per year for a
> professional license from Autodesk.  The spin meistering of the
> announcement would make George Orwell proud.  I don't see any way they
> can keep me from just using the license I currently own, at least
> on the OS's it supports.  (Parenthetically, like many users, I
> am also digging in my heels in terms of staying at Windows 7).
>
> Still, the question arises:  are there any affordable alternatives?
> Don't have to be entirely free.  I am looking for any trends out
> there as to what tool will attract a critical mass of users in
> the future.  There is strength in numbers.
>
> Comments?
>
> Rick N6RK
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Re: [time-nuts] Temperature (environmental) sensors

[Didier Juges]

I have C code (for the 8051) that is simply the translation of what's in the 
app note. It does temperature and humidity but not the barometric pressure (no 
double precision float on that compiler).

Works exactly as advertised. I have two.

You can see one in action here:

http://www.ko4bb.com/tps/plottemp.php?file=D8B04CF343D6.csv=day

This is my wife's green house, with temperature in C and F and humidity.

Let me know if you are interested.

Didier KO4BB 


On January 4, 2017 1:32:24 PM CST, Dan Kemppainen  
wrote:
>Hi All,
>
>Just ordered a few of these BME280 sensor boards. Also ordered a FTDI 
>C232HM cable to try to SPI or to bit-bang data from the board directly 
>to the PC. If a PIC or similar is required, does anyone on the list
>have 
>16Bit PIC code (pic24/dsPIC) C code for reading these BME280 sensors 
>laying around?
>
>They really look like a neat little unit. Thanks to all for the heads
>up 
>on these ones!
>
>Dan
>
>
>
>
>On 1/4/2017 12:00 PM, time-nuts-requ...@febo.com wrote:
>> Message: 7
>> Date: Wed, 4 Jan 2017 09:53:24 -
>> From: "David J Taylor" 
>> To: "Discussion of precise time and frequency measurement"
>>  
>> Subject: Re: [time-nuts] Temperature (environmental) sensors
>> Message-ID: <076CCA551DC142C2A8D93CF02A4AD1A3@Alta>
>> Content-Type: text/plain; format=flowed; charset="UTF-8";
>>  reply-type=original
>>
>> I like the Bosch BME280 conneced to a Raspberry PI.
>>
>https://learn.adafruit.com/adafruit-bme280-humidity-barometric-pressure-temperature-sensor-breakout/pinouts
>>
>https://github.com/adafruit/Adafruit_Python_BME280/blob/master/README.md
>> --   Björn
>> 
>>
>> Some performance plots are here, with some comparison between the
>pressure
>> readings from various sensors.
>>
>>   http://www.satsignal.eu/mrtg/performance_air_temp.php
>>
>> This is on mixed Windows/Linux platforms.
>>
>> Cheers,
>> David
>> -- SatSignal Software - Quality software written to your requirements
>> Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk
>> Twitter: @gm8arv
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Re: [time-nuts] HP53132A Firmware Version 4613

[Didier Juges]

Hopefully that will be tomorrow.

Didier KO4BB 


On December 27, 2016 2:37:23 PM CST, GandalfG8--- via time-nuts 
 wrote:
>I have just uploaded this firmware to Didier's (KO4BB) manuals site so 
>it 
>should be available for download in the near future.
> 
>Regards
> 
>Nigel
>GM8PZR
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Re: [time-nuts] Ublox M8N - have I a XO or TCXO ?

[Didier Juges]

TCXO usually refers to Temperature Compensated Crystal Oscillator (no heater), 
as opposed to Oven Controlled Crystal Oscillator (OCXO) which has an oven.
I would not expect a TCXO to become warm or draw more current at power up. An 
OCXO would.

Didier KO4BB

On December 21, 2016 1:29:00 PM CST, Mike Millen  
wrote:
>
> Can anyone comment on the following data, and whether they think
>the
>
> oscillator in "my" M8N is a XO or a TCXO ?
>
>
>Can you monitor the current draw from cold (ambient)?
>
>You may be able to identify the initial steady current drawn by the
>TCXO
>heater, then the cycling once it's hit the right temp?
>
>If there's no change at all in average current as it warms then it may
>not have a TCXO.
>
>Mike
>
>
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Re: [time-nuts] OT: ExpressPCB (cross-post from volts-nuts)

[Didier Juges]

There is a free tool (Robot Room Copper Connection) that will take EcpressPCB 
files and spit Gerber files. It is actually a full fledged PCB design software 
that seems to be significantly more capable than the ExpressPCB software even 
though I have not used it as such. 

Alternately you can send some money to ExpressPCB and they send you the Gerber, 
but only if you have actually bought the boards from them. So I usually get my 
first 3 prototypes from ExpressPCB and if I need to make small changes and feel 
comfortable buying production quantities without a second set of prototypes, I 
make the mods and get the Gerber from CC.


On December 9, 2016 2:07:10 PM CST, "Dr. David Kirkby (Kirkby Microwave Ltd)" 
 wrote:
>On 9 December 2016 at 19:58, BIll Ezell  wrote:
>> Sorry if I'm behind the times, just did a new project that required a
>pcb,
>> and ExpressPCB is my go-to vendor for one-off boards. I just noticed
>they
>> now provide the low-cost boards (fixed size, 3x5, quantity 3) that
>I've
>> always ordered with silk screen and solder mask for $71. I got my
>latest
>> boards that way and they're beautiful. No relationship to them, just
>a happy
>> customer. You can still get the barebones boards for $51.
>
>You also lock yourself into one vendor. There's other free software,
>like Kicad, where you can export files that many PCB manufacturers
>use. So you avoid vendor lock-in.
>
>https://en.wikipedia.org/wiki/Vendor_lock-in
>
>If the company goes belly up, where are you going to get any more
>boards made, without starting from scratch?
>
>Anyway, it is a bit off topic.
>
>Dave
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Re: [time-nuts] Oscilloquartz Star-4 GPSDO (was: Thermal impact on OCXO)

[Didier Juges]

Re: Manual uploads to my site:

I have limited internet access for another week. Uploads will be processed the 
week of December 5th.

Didier KO4BB


On November 19, 2016 7:05:52 PM GMT+01:00, Mark Sims  wrote:
>There was a copy uploaded to EEVBLOG.   I uploaded it  and another one
>that Atilla found to ko4bb.com  I don't know if they are out of
>quarantine yet.
>
>The device does not provide any PPS/OSC info to plot (only a 0.03C res
>temperature reading).   You can set the PLL time constant,  satellite
>elevation mask,  enter manual holdover.It does track SBAS
>satellites.  It also sees sat PRN 4,  which is not-active.
>
>The BG7TBL Star-4 GPSDO does not make the management interface
>available on the RS-232 connector.  I wired an external RS-232
>converter to the management port (he breaks out the 26-pin Star-4
>connector to pads).  I will probably re-wire his RS-232 signals (which
>are tapped off an internal Ublox serial interface) to the management
>port and get rid of my kludge.  His output normally sends out NMEA
>data, but once you talk to the management port, it switches to Ublox
>binary data.  Sending commands to the Ublox does not appear to do
>anything.  The BG7TBL device uses the ATDC version of the Star-4 which
>is the highest spec'd version.
>
>I may also bring out the Star-4 TOD (time of day) signal (which is a
>4800 BPS NMEA port) to the connector so NTP has something to get time
>messages from.
>
>---
>
>> Are Oscilloquartz's Star-4 commands described somewhere? I can't find
>them in the wild...
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Re: [time-nuts] HP 59309A Clock runs, sets via GPIB, but no GPIB output?

[Didier Juges]

I am out of town but will be back over the week end. All uploads will be sorted 
by then.

Didier KO4BB


On October 11, 2016 1:54:06 PM EDT, Francesco Messineo 
 wrote:
>1818-2295A dump has been uploaded to ko4bb site, probably there's need
>to be moved in the right place before it's available.
>
>On Mon, Oct 10, 2016 at 9:32 AM, Francesco Messineo
> wrote:
>> Hi Dave,
>> right, once I find the dumps, I'll upload them.
>> thanks
>> Frank IZ8DWF
>>
>> On Mon, Oct 10, 2016 at 9:24 AM, Artek Manuals
> wrote:
>>> Frank
>>>
>>> One of the best places to store ROM dumps for easy access by everyon
>is
>>> KO4BB.com
>>>
>>> Dave
>>> NR1DX
>>> dit dit
>>>
>>> On 10/10/2016 3:20 AM, Francesco Messineo wrote:

 I have a dump of the 1818-2295A somewhere, it should be archived in
 one of my backups. I also made a replacement with a board having 2
>x
 28C64 SO-28 eeproms and it worked in my 59309A as far as I could
>test
 it. However these eeproms present many glitches on the outputs
>during
 address toggling, so it's way better to use a suitable CPLD after
 recovering the equations (I'm a bit stuck on this project due to
>lack
 of time...).
 If someone needs the dump, just let me know and I'll dig it out.
 HTH
 Frank IZ8DWF
>>>
>>>
>>>
>>> --
>>> Dave
>>> manu...@artekmanuals.com
>>> www.ArtekManuals.com
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Re: [time-nuts] Prologix USB-GPIB Controller

[Didier Juges]

I buy a lot of stuff from eBay and Amazon, including batteries on occasion. 
Invariably, there has been a pretty good correlation between price and quality, 
but considerably more so with batteries. 

It really sucks paying $100 or more for a quality OEM laptop battery, but the 
alternative is to throw away $40 and getting junk that at best will not be very 
useful and at worse will burn your house.

Batteries are a tough business, ask Samsung...

Didier KO4BB

On October 10, 2016 1:13:45 PM EDT, "Dr. David Kirkby (Kirkby Microwave Ltd)" 
 wrote:
>On 10 October 2016 at 09:35, Charles Steinmetz 
>wrote:
>
>> Poul-Henning wrote:
>>
>> And for voltage references, "pre-owned" is likely to mean "better".
>>>
>>
>> Perhaps, but third-world recyclers are not known for gentle treatment
>> during the parts removal process.
>
>
>I had some cheap ($10) GPS receiver boards shipped to me in a plastic
>kitchen bag from yikunhk on eBay. 4 boards in the same bag, all
>scratching
>each other. The bag was not anti-static.
>
>There are all number of possible explanations of why boards can be made
>so
>cheaply, when the ICs appear to cost more than the boards.
>
>* The chips are counterfeit
>* The chips are similar to what they are supposed to be, but have been
>relabeled.
>* They are made at the same factory as the real devices, on what I've
>heard
>described as the "ghost shift", where they are not officially made, but
>are
>the same devices.
>* They are recycled.
>* They are stolen.
>
>It is anyone's guess once you start buying semiconductor devices from
>eBay.
>Maybe you are lucky, maybe you are not.
>
>You dramatically increase the probability a part is good if sourced
>from a
>reputable source (e.g. RS or Farnell in the UK). That is not to say
>that
>the parts are not counterfeits, as even the best suppliers can get
>caught,
>but they are more likely to be ok.
>
>I recently bought a supposedly original Samsung battery for my Samsung
>Galazy S3 phone from a local shop. The phone had all sorts of issues
>with
>this battery, so I concluded it was a poor counterfeit.  I thought I'd
>be
>safe buying directory from Amazon (not a 3rd party), but on reading
>reviews
>on Amazon, I was not convinced those were genuine Samsung batteries
>either,
>so I did not buy from Amazon.
>
>Eventually I bought a battery from the Samsung website. The phone now
>works
>ok.  I don't know if  Samsung actually make the batteries themselves,
>but I
>think I have a better chance of buying from the Samsung website than
>from
>anywhere else.
>
>I've had "Duracell" batteries leak. At one time I used to blame
>Duracell,
>but now it has cross my mind whether they might have been bought on
>eBay
>and were counterfeits. I can't recall where they were purchased, but
>now I
>will only purchase batteries from sources I consider reputable.
>
>Dave.
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Re: [time-nuts] Speaking clock

[Didier Juges]

I would like to find an emulator of the old voice synthesizer used in the
Atlanta airport subway. "The next stop is concourse A. The color coded maps
in this vehicle match the station colors." "This vehicle is leaving the
station, please hold on."
They replaced it in 1996 for the Olympics but I remember it as if it was
yesterday...
(I used to travel a lot)

Didier KO4BB


On Mon, Aug 8, 2016 at 6:28 AM, Morris Odell 
wrote:

> Hi all,
>
> There was a thread about this a few weeks ago and I mentioned that I was
> working on one with a "Stephen Hawking" voice - well here's a video:
>
> https://youtu.be/lmg0YsHlB3g
>
> So far it's not GPS controlled but that will come one day.
>
> Cheers,
>
> Morris
>
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Re: [time-nuts] GPSDO - probably a stupid question.

[Didier Juges]

In fact, you do not want to "update the crystal one million times/second".
The whole point of a GPSDO is to combine the excellent short term stability
of the crystal with the excellent long term stability of the GPS signal. If
you update the crystal in real time from the GPS data, you do not need the
crystal...
The control loop of GPSDOs usually have an effective bandwidth measured in
minutes or even hours in the case of rubidium oscillators.


On Wed, Aug 17, 2016 at 11:57 AM, Peter Reilley 
wrote:

> You can get crystal oscillators that have a frequency control signal and
> are more
> stable than the run of the mill oscillators.   Changing the GPS oscillator
> would
> require modifying a very tightly populated circuit board.   Perhaps not
> possible.
>
> What about some of the SDR (software defined radio) projects that aim to
> implement GPS functionality?   If you used the GPS chipping rate (1.023
> MHz)
> to dicipline the 10 MHz oscillator then you are less sensitive to crystal
> instabilities.
> You are updating the crystal one million times a second rather than once
> per second.
> This is assuming that the chipping rate of the transmitter is just as good
> as the
> 1 PPS signal.   This info from here;
> https://www.e-education.psu.edu/geog862/node/1753
> and here;
> https://en.wikipedia.org/wiki/GPS_signals
>
> Even using the 50 bits/sec data rate of the GPS signal would allow
> updating the
> GPSDO faster than the 1 PPS signal.
>
> Pete.
>
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Re: [time-nuts] Mini ovens packaging

[Didier Juges]

If you have to regulate over ambient temperature as high as 120C, you need
an oven that regulates at a higher temperature, maybe 125 at least or 130C.
You will have a lot of issues with long term reliability with something
that operates 24/7 above 120C.
Have you looked at a Peltier junction that would let you regulate at a
lower temperature like maybe 50C or so over the range you describe?
Peltier junctions can heat and cool and are not too difficult to use.
The actual temperature stability you try to achieve will dictate how much
insulation you need from the environment, but if you only need to regulate
within one or 2 C, you may not need a complete enclosure.

On Thu, Aug 11, 2016 at 4:05 AM, Guillermo Sobreviela Falces <
guillermo.sobrevi...@uab.cat> wrote:

> Dear all,
>
> I am currently looking for a temperature compensation system for an IC
> (Temperature range from -40°C to 120°C and chip area of 1cm x 1cm). This
> compensation system has to be external to the IC and, as the power
> consumption is not the main problem, I have been looking for a crystal
> oven. The ideal solution will be a PCB compatible oven, but it also can be
> an external element.
>
> I have found some mini ovens in http://www.isotemp.com/ (Set point +35°C
> to +95°C), but seem to be quite small for my IC. I would like to know if
> there are other companies selling only the oven packaging for OCXO systems
> with a similar size to this:
>
> http://www.vectron.com/products/ocxo/ox-208.pdf
>
> Greetings and thank you all in advance.
>
>
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Re: [time-nuts] Working with SMT parts.

[Didier Juges]

I did not know Futurlec accepted ExpressPCB files, so I checked.

The equivalent to ExpressPCB mini board pro service (2 sided, solder mask
and silk screen, 3 pieces, same size) is $86 + shipping and one week to
shipment. ExpressPCB is $75 in 3-4 days in your mailbox including FedEx
(they do offer cheaper/slower delivery methods).

I did not check other dimensions/quantities.


On Sat, Aug 13, 2016 at 2:14 AM, wb6bnq  wrote:

> Hello Orin,
>
> Like I mentioned before http://www.futurlec.com/PCBService.shtml will
> accept the ExpressPCB program file and their prices are very reasonable
> compared to having the work done through ExpressPCB themselves.
>
> BillWB6BNQ
>
> Orin Eman wrote:
>
> On Fri, Aug 12, 2016 at 7:25 PM, Brooke Clarke  wrote:
>>
>>
>>
>>> Hi Chris:
>>>
>>> ExpressPCB has very easy to use free software for schematic capture
>>> (later
>>> used to check the board wiring) and software for board layout including
>>> making custom components if their library of stock components does not
>>> have
>>> what you need.  The output file format is proprietary, which makes it
>>> interesting that Far Circuits can read it.
>>>
>>> I just have not wanted to go through learning curve for Gerber files and
>>> all the associated stuff (maybe drilling, silk screen, solder mask) which
>>> is very easy to do with ExpressPCB.
>>>
>>>
>>
>>
>>
>> I did my first 'CAD' PCB with EasyTrax... a DOS program.  Must have been
>> about 1998 as that's the copyright date I put on the board.
>>
>> Believe me, getting any of the current programs to produce gerber files is
>> trivial compared to using EasyTrax and making it produce gerber files.  In
>> fact, I usually us itead.cc for small boards and they provide the script
>> to
>> produce gerber files from Eagle, which is what I currently use.  I've also
>> used OSH Park and you can simply send an Eagle board file to them; just as
>> easy as using ExpressPCB without the expensive tie-in.
>>
>> I must admit ExpressPCB leaves me with a sour taste - many published
>> projects seem to use them as  I suppose the author liked the free
>> software.  But then everyone that uses the ExpressPCB files that the
>> author
>> supplies pays the ExpressPCB premium.  $300 in one case and the boards
>> weren't even flat!
>>
>> Orin.
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>> and follow the instructions there.
>>
>>
>>
>
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Re: [time-nuts] Working with SMT parts.

[Didier Juges]

Hi Bill,

I used Futurlec once and I was very happy with the results, but now most of my 
projects involve quantities of 50 or more pieces so I have the production 
quantities PWB made and the product assembly done (parts procurement, soldering 
and test) in a very large far Eastern country, kinda like Apple but on a 
slightly smaller scale...

I have now worked with the same company for 7-8 years and I am quite satisfied 
with the results and the prices, for well over 3,000 pieces in total.

As long as there are no long lead parts, I get finished products in the DHL 
about 3-4 weeks ARO from emailing them the Gerber's.

Didier KO4BB


On August 12, 2016 9:22:42 AM CDT, wb6bnq <wb6...@cox.net> wrote:
>Hi Didier,
>
>I use ExpressPCB as well, but I send the ExpressPCB file to a company 
>called Futurlec
>( http://www.futurlec.com/PCBService.shtml ).  They have reasonable 
>prices.  Because it is overseas it takes about three weeks to get the 
>product back.  So far I have been very impressed with the product I 
>recieved.  I have even had notches done in the four corners to fit a 
>plastic box that came out very well.
>
>Also, There is a person who started to write his own version  of layout
>
>program based off of the ExpressPCB program called  "Copper 
>Connection."  (  http://www.robotroom.com/CopperConnection/index.html )
> 
>It is a bit more involved than the ExpressPCB program and does have 
>GERBER files as a selection.  However he charges for the program but it
>
>seems the prices are reasonable ( 
>http://www.robotroom.com/CopperConnection/Buy.html ).
>
>73BillWB6BNQ
>
>
>Didier Juges wrote:
>
>>The way ExpressPCB works is that their free software produces boards
>in a proprietary format, and you have to pay to convert their design
>file to Gerber.
>>
>>Your mileage may vary but I found the combination of design tools
>learning curve, board quality and quick service to be worthwhile to me.
>>
>>I have tried Eagle twice and never could manage to build the models I
>needed. It may have been an issue of not finding the right tutorial but
>I have produced several ExpressPCB designs in less time than I have
>tried (unsuccessfully) to produce a single schematic in Eagle, let
>alone a PWB. Since it is a hobby that has become a business, time
>matters to me, design time and delivery.
>>
>>At that point, the cost of the Gerber becomes somewhat irrelevant.
>>
>>Note that you can make boards of any size in ExpressPCB.
>>
>>I am not advocating it is the best solution for everyone, I personally
>would like to be proficient with Eagle, but Express PCB works for me.
>>
>>Didier KO4BB
>>
>>
>>
>>
>>On August 11, 2016 10:45:45 PM CDT, Chris Albertson
><albertson.ch...@gmail.com> wrote:
>>  
>>
>>>This seems totally backwards.  Typically a Gerber file is something
>>>you make yourself on your computer then send it in for a prototype.
>>>Seems odd to buy them.
>>>
>>>I checked ExpressPCB prices and they are very high.  I can get PCBs
>>>made quickly in the US for $3 per square inch, shipping included with
>>>$9 minimum order.  And  you don't buy the Gerbers.
>>>
>>>I notice ExpressPCB offers free software.  But it is totally
>>>non-standard and you can't use it for anything other then for their
>>>service.  Most people needing free PCB software use Eagle, some use
>>>Kicad or some others.  But Eagle seems to be kind of a universal
>>>standard.
>>>
>>>
>>>
>>>
>>>On Thu, Aug 11, 2016 at 8:55 AM, Didier Juges <shali...@gmail.com>
>>>wrote:
>>>
>>>
>>>>I concur. I have been using ExpressPCB extensively over the last 2
>>>>  
>>>>
>>>years
>>>
>>>
>>>>with great satisfaction now that it is possible to get Gerber files
>>>>  
>>>>
>>>from
>>>
>>>
>>>>them.
>>>>I typically use the mini board pro service (3 bare boards, 2 sided
>>>>  
>>>>
>>>with
>>>
>>>
>>>>solder mask and silk screen) for prototypes and then buy the Gerbers
>>>>  
>>>>
>>>-- 
>>>
>>>Chris Albertson
>>>Redondo Beach, California
>>>___
>>>time-nuts mailing list -- time-nuts@febo.com
>>>To unsubscribe, go to
>>>https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>and follow the instructions there.
>>>
>>>
>>
>>  
>>
>
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Re: [time-nuts] Working with SMT parts.

[Didier Juges]

I just installed CopperConnection and it opens the ExpressPCB layouts just fine 
:)

Thanks for the tip, I will give it a go.

Didier KO4BB

On August 12, 2016 9:22:42 AM CDT, wb6bnq <wb6...@cox.net> wrote:
>Hi Didier,
>
>I use ExpressPCB as well, but I send the ExpressPCB file to a company 
>called Futurlec
>( http://www.futurlec.com/PCBService.shtml ).  They have reasonable 
>prices.  Because it is overseas it takes about three weeks to get the 
>product back.  So far I have been very impressed with the product I 
>recieved.  I have even had notches done in the four corners to fit a 
>plastic box that came out very well.
>
>Also, There is a person who started to write his own version  of layout
>
>program based off of the ExpressPCB program called  "Copper 
>Connection."  (  http://www.robotroom.com/CopperConnection/index.html )
> 
>It is a bit more involved than the ExpressPCB program and does have 
>GERBER files as a selection.  However he charges for the program but it
>
>seems the prices are reasonable ( 
>http://www.robotroom.com/CopperConnection/Buy.html ).
>
>73BillWB6BNQ
>
>
>Didier Juges wrote:
>
>>The way ExpressPCB works is that their free software produces boards
>in a proprietary format, and you have to pay to convert their design
>file to Gerber.
>>
>>Your mileage may vary but I found the combination of design tools
>learning curve, board quality and quick service to be worthwhile to me.
>>
>>I have tried Eagle twice and never could manage to build the models I
>needed. It may have been an issue of not finding the right tutorial but
>I have produced several ExpressPCB designs in less time than I have
>tried (unsuccessfully) to produce a single schematic in Eagle, let
>alone a PWB. Since it is a hobby that has become a business, time
>matters to me, design time and delivery.
>>
>>At that point, the cost of the Gerber becomes somewhat irrelevant.
>>
>>Note that you can make boards of any size in ExpressPCB.
>>
>>I am not advocating it is the best solution for everyone, I personally
>would like to be proficient with Eagle, but Express PCB works for me.
>>
>>Didier KO4BB
>>
>>
>>
>>
>>On August 11, 2016 10:45:45 PM CDT, Chris Albertson
><albertson.ch...@gmail.com> wrote:
>>  
>>
>>>This seems totally backwards.  Typically a Gerber file is something
>>>you make yourself on your computer then send it in for a prototype.
>>>Seems odd to buy them.
>>>
>>>I checked ExpressPCB prices and they are very high.  I can get PCBs
>>>made quickly in the US for $3 per square inch, shipping included with
>>>$9 minimum order.  And  you don't buy the Gerbers.
>>>
>>>I notice ExpressPCB offers free software.  But it is totally
>>>non-standard and you can't use it for anything other then for their
>>>service.  Most people needing free PCB software use Eagle, some use
>>>Kicad or some others.  But Eagle seems to be kind of a universal
>>>standard.
>>>
>>>
>>>
>>>
>>>On Thu, Aug 11, 2016 at 8:55 AM, Didier Juges <shali...@gmail.com>
>>>wrote:
>>>
>>>
>>>>I concur. I have been using ExpressPCB extensively over the last 2
>>>>  
>>>>
>>>years
>>>
>>>
>>>>with great satisfaction now that it is possible to get Gerber files
>>>>  
>>>>
>>>from
>>>
>>>
>>>>them.
>>>>I typically use the mini board pro service (3 bare boards, 2 sided
>>>>  
>>>>
>>>with
>>>
>>>
>>>>solder mask and silk screen) for prototypes and then buy the Gerbers
>>>>  
>>>>
>>>-- 
>>>
>>>Chris Albertson
>>>Redondo Beach, California
>>>___
>>>time-nuts mailing list -- time-nuts@febo.com
>>>To unsubscribe, go to
>>>https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>>and follow the instructions there.
>>>
>>>
>>
>>  
>>
>
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Re: [time-nuts] Working with SMT parts.

[Didier Juges]

The way ExpressPCB works is that their free software produces boards in a 
proprietary format, and you have to pay to convert their design file to Gerber.

Your mileage may vary but I found the combination of design tools learning 
curve, board quality and quick service to be worthwhile to me.

I have tried Eagle twice and never could manage to build the models I needed. 
It may have been an issue of not finding the right tutorial but I have produced 
several ExpressPCB designs in less time than I have tried (unsuccessfully) to 
produce a single schematic in Eagle, let alone a PWB. Since it is a hobby that 
has become a business, time matters to me, design time and delivery.

At that point, the cost of the Gerber becomes somewhat irrelevant.

Note that you can make boards of any size in ExpressPCB.

I am not advocating it is the best solution for everyone, I personally would 
like to be proficient with Eagle, but Express PCB works for me.

Didier KO4BB




On August 11, 2016 10:45:45 PM CDT, Chris Albertson <albertson.ch...@gmail.com> 
wrote:
>This seems totally backwards.  Typically a Gerber file is something
>you make yourself on your computer then send it in for a prototype.
>Seems odd to buy them.
>
>I checked ExpressPCB prices and they are very high.  I can get PCBs
>made quickly in the US for $3 per square inch, shipping included with
>$9 minimum order.  And  you don't buy the Gerbers.
>
>I notice ExpressPCB offers free software.  But it is totally
>non-standard and you can't use it for anything other then for their
>service.  Most people needing free PCB software use Eagle, some use
>Kicad or some others.  But Eagle seems to be kind of a universal
>standard.
>
>
>
>
>On Thu, Aug 11, 2016 at 8:55 AM, Didier Juges <shali...@gmail.com>
>wrote:
>> I concur. I have been using ExpressPCB extensively over the last 2
>years
>> with great satisfaction now that it is possible to get Gerber files
>from
>> them.
>> I typically use the mini board pro service (3 bare boards, 2 sided
>with
>> solder mask and silk screen) for prototypes and then buy the Gerbers
>
>-- 
>
>Chris Albertson
>Redondo Beach, California
>___
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Re: [time-nuts] Safely getting the electrical length of a connected antenna feedline

[Didier Juges]

Good point! It is only an issue when you try to calibrate/correlate to the 
physical length.
Didier

On August 11, 2016 1:56:09 PM CDT, Bob Stewart <b...@evoria.net> wrote:
>Why is velocity factor an issue?  Aren't we only interested in the
>electrical time from one end of the coax to the other?
>Bob
> -
>AE6RV.com
>
>GFS GPSDO list:
>groups.yahoo.com/neo/groups/GFS-GPSDOs/info
>
>  From: Didier Juges <shali...@gmail.com>
>To: Bob Albert <bob91...@yahoo.com>; Discussion of precise time and
>frequency measurement <time-nuts@febo.com> 
> Sent: Thursday, August 11, 2016 1:20 PM
>Subject: Re: [time-nuts] Safely getting the electrical length of a
>connected antenna feedline
>   
>I used the PPS from a Thunderbolt (fast rise lime, low rep frequency,
>was handy) and a digital storage scope and a couple of resistors to
>make a reflectometer based on this experiment:
>
>www.ko4bb.com/getsimple/index.php?I'd=coax-cable-impedance-matching
>
>You can very clearly see a 50 ohm/75 ohm mismatch.
>
>The biggest variable will be the velocity factor.
>
>Didier KO4BB
>
>  
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Re: [time-nuts] Safely getting the electrical length of a connectedantenna feedline

[Didier Juges]

Thank you Tom and yes, the spell checker tends to be overbearing at times

Didier

On August 11, 2016 3:19:04 PM CDT, Tom Van Baak <t...@leapsecond.com> wrote:
>FYI: In Didier's post below, the correct URL is:
>
>http://www.ko4bb.com/getsimple/index.php?id=coax-cable-impedance-matching
>
>I'm guessing a mobile spell checker changed his " id= " to " I'd= "
>(even though it was part of a URL).
>
>/tvb
>
>- Original Message - 
>From: "Didier Juges" <shali...@gmail.com>
>To: "Bob Albert" <bob91...@yahoo.com>; "Discussion of precise time and
>frequency measurement" <time-nuts@febo.com>
>Sent: Thursday, August 11, 2016 11:20 AM
>Subject: Re: [time-nuts] Safely getting the electrical length of a
>connectedantenna feedline
>
>
>I used the PPS from a Thunderbolt (fast rise lime, low rep frequency,
>was handy) and a digital storage scope and a couple of resistors to
>make a reflectometer based on this experiment:
>
>www.ko4bb.com/getsimple/index.php?I'd=coax-cable-impedance-matching
>
>You can very clearly see a 50 ohm/75 ohm mismatch.
>
>The biggest variable will be the velocity factor.
>
>Didier KO4BB
>
>
>On August 8, 2016 2:18:02 PM CDT, Bob Albert via time-nuts
><time-nuts@febo.com> wrote:
>>I host a group called something like HF Antennas. There I posted a
>>link to an article on how to measure coaxial cable. The easiest way is
>>with a spectrum analyzer and a tracking generator.
>>You connect the generator to the analyzer through a Tee that goes to
>>the unknown coax. You will see a group of peaks and nulls over the
>>spectrum. The spacing is a half wave of the cable. The match needs to
>>not be good to see the nulls best, and you will need to know the
>>propagation constant of the cable. Chances are, the match won't be
>>good over the entire range so you are okay with that. Propagation
>>constant of most coaxial cable runs around 66%.
>>You can also use a TDR setup but you'll have to make one, with a
>pulser
>>and a 'scope. I downloaded a circuit for a pulser that uses one IC. I
>>have the parts but haven't built it yet, as I am stalled by the
>problem
>>of connecting to a 14 pin SMD part. The IC uses one part as an
>>oscillator and the other 5 in parallel to drive 50 Ohms. Again, you
>>use a Tee and measure the time for a reflection, bearing in mind that
>>the trip is two ways over the same cable and the time shown will be
>>double the time for the calculation.
>>Bob
>> 
>>
>>On Monday, August 8, 2016 12:00 PM, Bob Stewart <b...@evoria.net>
>wrote:
>> 
>>
>>Earlier this year, with some help, I pulled the dish off of an old
>>DishTV antenna on the roof and put a 5V bullet antenna on the mast. I
>>also pulled a new cable through by attaching it to the old one. The
>>problem is that I was not able to measure the new cable. So, the
>>question is, without going back on the roof in this heat, how can I
>>measure the electrical length of the line I pulled? 
>>
>>I was thinking of using my 8640B signal generator and sending some RF
>>back up the line to get a quarter wavelength at the null. But that
>>assumes a lot, including that the other end is open at 3MHz, or
>>whatever the frequency works out to be, as well as that the high
>>voltage on the antenna end won't be high enough to blow the LNA.
>>
>>So, how much RF I can safely send up the line? I've got an 8558B
>>spectrum analyzer, but it's not on the bench, and it would be easier
>to
>>use my scope, which sadly is a 70s vintage Tek 455. Do I put this all
>>together with a lead from the generator to a tee at the measuring
>>device and tune for a null? My experience at getting precise
>>measurements on anything longer than a few inches is effectively none,
>>but I'd guess that I want less than 0.5V at the LNA during this test. 
>>Oh, and I do have an 8444A tracking generator that can output -10 dbm
>>as well as a 10 db attenuator within easy access. That could get a
>>quick spot on the null point.
>>
>>Most importantly, of course is the question of whether this will even
>>work. 
>>
>>Bob -
>>AE6RV
>-
>>AE6RV.com
>>
>>GFS GPSDO list:
>>groups.yahoo.com/neo/groups/GFS-GPSDOs/info
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>>and follow the instructions there.
>>
>>
>>  
&

Re: [time-nuts] Safely getting the electrical length of a connected antenna feedline

[Didier Juges]

I used the PPS from a Thunderbolt (fast rise lime, low rep frequency, was 
handy) and a digital storage scope and a couple of resistors to make a 
reflectometer based on this experiment:

www.ko4bb.com/getsimple/index.php?I'd=coax-cable-impedance-matching

You can very clearly see a 50 ohm/75 ohm mismatch.

The biggest variable will be the velocity factor.

Didier KO4BB


On August 8, 2016 2:18:02 PM CDT, Bob Albert via time-nuts  
wrote:
>I host a group called something like HF Antennas.  There I posted a
>link to an article on how to measure coaxial cable.  The easiest way is
>with a spectrum analyzer and a tracking generator.
>You connect the generator to the analyzer through a Tee that goes to
>the unknown coax.  You will see a group of peaks and nulls over the
>spectrum.  The spacing is a half wave of the cable.  The match needs to
>not be good to see the nulls best, and you will need to know the
>propagation constant of the cable.  Chances are, the match won't be
>good over the entire range so you are okay with that.  Propagation
>constant of most coaxial cable runs around 66%.
>You can also use a TDR setup but you'll have to make one, with a pulser
>and a 'scope.  I downloaded a circuit for a pulser that uses one IC.  I
>have the parts but haven't built it yet, as I am stalled by the problem
>of connecting to a 14 pin SMD part.  The IC uses one part as an
>oscillator and the other 5 in parallel to drive 50 Ohms.  Again, you
>use a Tee and measure the time for a reflection, bearing in mind that
>the trip is two ways over the same cable and the time shown will be
>double the time for the calculation.
>Bob
> 
>
>On Monday, August 8, 2016 12:00 PM, Bob Stewart  wrote:
> 
>
>Earlier this year, with some help, I pulled the dish off of an old
>DishTV antenna on the roof and put a 5V bullet antenna on the mast.  I
>also pulled a new cable through by attaching it to the old one.  The
>problem is that I was not able to measure the new cable.  So, the
>question is, without going back on the roof in this heat, how can I
>measure the electrical length of the line I pulled?  
>
>I was thinking of using my 8640B signal generator and sending some RF
>back up the line to get a quarter wavelength at the null.  But that
>assumes a lot, including that the other end is open at 3MHz, or
>whatever the frequency works out to be, as well as that the high
>voltage on the antenna end won't be high enough to blow the LNA.
>
>So, how much RF I can safely send up the line?  I've got an 8558B
>spectrum analyzer, but it's not on the bench, and it would be easier to
>use my scope, which sadly is a 70s vintage Tek 455.  Do I put this all
>together with a lead from the generator to a tee at the measuring
>device and tune for a null?  My experience at getting precise
>measurements on anything longer than a few inches is effectively none,
>but I'd guess that I want less than 0.5V at the LNA during this test. 
>Oh, and I do have an 8444A tracking generator that can output -10 dbm
>as well as a 10 db attenuator within easy access.  That could get a
>quick spot on the null point.
>
>Most importantly, of course is the question of whether this will even
>work.  
>
>Bob -
>AE6RV -
>AE6RV.com
>
>GFS GPSDO list:
>groups.yahoo.com/neo/groups/GFS-GPSDOs/info
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>
>  
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Re: [time-nuts] Working with SMT parts.

[Didier Juges]

I concur. I have been using ExpressPCB extensively over the last 2 years
with great satisfaction now that it is possible to get Gerber files from
them.
I typically use the mini board pro service (3 bare boards, 2 sided with
solder mask and silk screen) for prototypes and then buy the Gerbers to
have production quantities done overseas.
The boards are of high quality and the service is very fast at a very
reasonable price.
The only gotcha with regard to Gerber files is that you can only buy
Gerbers for boards that you have actually bought from them, so the process
is to buy the prototypes, then if you are happy with those, buy the Gerbers
for that design.

Didier KO4BB

On Tue, Aug 9, 2016 at 3:06 PM, Brooke Clarke  wrote:

> Hi:
>
> I've had good luck using any of the the ExpressPCB services that include
> solder mask with surface mount parts where the pitch is 0.05" (half normal
> DIP) and hand soldering (requires stereo microscope).
> http://www.prc68.com/I/BTSG.shtml (battery top signal generator)
> http://www.prc68.com/I/Images/ICS525v1o.jpg
>
> http://www.prc68.com/I/SMT.shtml 
>
> --
> Have Fun,
>
> Brooke Clarke
> http://www.PRC68.com
> http://www.end2partygovernment.com/2012Issues.html
> The lesser of evils is still evil.
>
>
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[time-nuts] KO4BB Manuals

[Didier Juges]

Thank you to those who let me know of an issue with my Manuals site last
week and this week.

It turns out that the primary issue was not lack of disk space (even though
that was going to be an issue very soon, so that has been fixed
preemptively) but an issue with the download app.

In the process of fixing this (which is now complete), I noticed that about
3.7 millions pdf documents have been downloaded from my site through the
manuals download app since October 2014. That's about 168,000/month average.

The time-nuts group as a whole has been supplying a significant portion of
the visitors overall but by far the biggest downloader has been the Chinese
site Baidu. It seems like they have downloaded the 26,000 files I have
several times over... Still a very small fraction of the total, which
includes visitors from over 200 countries.

Thank you all for your participation and support!

Didier KO4BB

www.ko4bb.com
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Re: [time-nuts] Very Accurate Delta Time RF Pulse Measurements

[Didier Juges]

Have you looked at the blitzortung.org system?
There may be some ideas to glean from that


On July 28, 2016 6:12:54 PM CDT, Jerome Blaha  
wrote:
>Hi Guys,
>
>This is a little outside of time-nuts scope, but not by much.  I'm
>interested in finding the time between two rising edges above a set
>threshold with preferably nS or high ps timing accuracy.  Can this be
>simply done with a few programmed Microchip PICs or with a good short
>term OCXO clock?  The issue I see is that a 10Mhz timing reference with
>1 cycle difference in time yields 100ns resolution, which is far too
>large, so maybe a PIC can solve this.
>
>This weekend project would be a multi-element antenna array, each with
>a super-fast response log peak power detector fed into several PICs for
>time of arrival.  Whenever a nearby high energy RF pulse is detected,
>the time of arrival between two antenna elements and hence the
>direction toward the TX could be roughly computed.  Some typical log
>peak detectors have an 8ns input pulse response time, so I'm hoping
>that rise times are similar between multiple detectors, negating the
>delayed response.
>
>There are time of arrival/AoA systems out there with synthetic doppler,
>phased arrays, correlative interferometers, and phase comparators, but
>it would be interesting to accomplish super wideband AoA timing on two
>rising pulses with relatively cheap parts. 
>
>Thanks,
>
>-Jerome
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[time-nuts] KO4BB out of space

[Didier Juges]

KO4BB.com ran out of disk space.


Apparently the Control Panel indicated I was using 120GB out of 160
available, but it was off by about 40GB...


About 90GB of that are manuals.


A good bit of the extra are duplicate files that resulted from the site
hosting transfer a couple of years ago that I had planned to clean up at
some point. I was just not planning to do that NOW!!!


The problem has been temporarily fixed, I have freed 10GB and hopefully I
will have made more space (or bought more space...) over the week end.


Thank you for your patience and your support.


Didier KO4BB
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Re: [time-nuts] KS-24361 rom

[Didier Juges]

I will be glad to host it of course, but you cannot directly post it to a
particular directory, you just upload it and I will move it.

Please note that the HP guy who was instrumental to establishing the
obsolete manuals on the HP site (Dave Cunningham was his name I believe)
actually asked me if it was OK for him to download manuals they had lost
from my web site, so I would say that most likely
HP/Agilent/Keysight/whatnot is perfectly OK with this, or at least they
were at one time. Caveat emptor...

In cases where there are instructions and/or notes going with an upload,
the best is to add the instruction/note in a .readme.txt file matching
the name of the file that it relates to, and upload both, or put a
README.txt with the file and zip both together. Do not zip large pdf files
though. It yields little gain in size and makes my job harder because I
have to ssh into the machine to unzip it instead of just moving/renaming
via ftp.

Didier KO4BB

On Sat, Apr 16, 2016 at 5:36 AM, Tom Van Baak  wrote:

> Adrian,
>
> Thanks for doing that. And you're now a member of the hp Smartclock pForth
> appreciation club ;-)
>
> You can send the ROM to me or Magnus, or better yet post it under "01 ROM
> Images and Drivers" at Didier's site:
>
> http://www.ko4bb.com/manuals/
>
> /tvb
>
>
> - Original Message -
> From: "Adrian Godwin" 
> To: "Discussion of precise time and frequency measurement" <
> time-nuts@febo.com>
> Sent: Friday, April 15, 2016 1:56 PM
> Subject: [time-nuts] KS-24361 rom
>
>
> > I've dumped out the KS24361 ROM using the built-in Forth interpreter as a
> > move towards reverse-engineering it.
> >
> > Is there somewhere I can put this for easy access ? I imagine it's
> > copyright HP and although I doubt they'll care, I don't want to cause any
> > problems.
> >
> > -adrian
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Re: [time-nuts] Unix software to generate nice looking *DEV plots

[Didier Juges]

Here is what my tool looks like:
www.eds-fl.com/misc/graph/index.php

You need to download a data file first, I added a link to download a small file 
9kB.

Again, this is not an ADEV tool, the file format is binary (came out of an old 
DOS tool that could not plot to save its life...) but it's an example. Some 
advantages are that you do not need to install anything on your computer and it 
is by default multiplatform :)


On March 17, 2016 7:25:08 AM CDT, John Ackermann N8UR  wrote:
>Hi Attila --
>
>I have some stuff that does ADEV and similar calculations and shoves
>the 
>results into plots using the Grace plotting tool.  It's basically a
>perl 
>script using some document formatting templates and a couple of shell 
>scripts for control.  I use it to automagically create web pages such
>as 
>those at
>
>http://www.febo.com/pages/plots/chronos/
>
>Let me know off list if you're interested and I can package up the 
>latest version; I'm working on an update now.
>
>John
>
>
>On 3/17/2016 6:29 AM, Attila Kinali wrote:
>> Moin,
>>
>> I'm looking for some non-GUI software to generate the different *DEV
>> plots we generally use to asses oscillators with. Timelab is nice,
>> but if you are evaluating two dozen measurements using different
>> parameters, it becomes very tedious to generate the plots. Not
>> to talk about the problem that the plots are not really reproducable,
>> which is a very important property, when publishing results.
>>
>> I could for sure write myself wrappers around
>gnuplot/ploticus/mathplotlib/..
>> to generate the *DEV plots, but I'm not keen on reinventing the
>wheel.
>>
>> Thus I'd like to ask whether someone has any hints on what to use.
>>
>>  Attila Kinali
>>
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Re: [time-nuts] Unix software to generate nice looking *DEV plots

[Didier Juges]

I have done something similar at work (not for adev, for plots of corona test 
results on HV transformers) but since most engineers here are Linux/UNIX 
challenged, I put the Perl scripts on a Linux box and let people send their 
data through a web page via cgi, which returns the plot as graphic.
Everybody knows how to do that (upload data through a web page) and all the 
plots look the same (as far as formatting and such are concerned)
I could give it a shot if you send me the Perl scripts.

On March 17, 2016 7:25:08 AM CDT, John Ackermann N8UR  wrote:
>Hi Attila --
>
>I have some stuff that does ADEV and similar calculations and shoves
>the 
>results into plots using the Grace plotting tool.  It's basically a
>perl 
>script using some document formatting templates and a couple of shell 
>scripts for control.  I use it to automagically create web pages such
>as 
>those at
>
>http://www.febo.com/pages/plots/chronos/
>
>Let me know off list if you're interested and I can package up the 
>latest version; I'm working on an update now.
>
>John
>
>
>On 3/17/2016 6:29 AM, Attila Kinali wrote:
>> Moin,
>>
>> I'm looking for some non-GUI software to generate the different *DEV
>> plots we generally use to asses oscillators with. Timelab is nice,
>> but if you are evaluating two dozen measurements using different
>> parameters, it becomes very tedious to generate the plots. Not
>> to talk about the problem that the plots are not really reproducable,
>> which is a very important property, when publishing results.
>>
>> I could for sure write myself wrappers around
>gnuplot/ploticus/mathplotlib/..
>> to generate the *DEV plots, but I'm not keen on reinventing the
>wheel.
>>
>> Thus I'd like to ask whether someone has any hints on what to use.
>>
>>  Attila Kinali
>>
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Re: [time-nuts] For those of us that did the CPU upgrade for the 5370

[Didier Juges]

Hopefully, they will have installed the U.FL connector on the WiFi board so 
that you can install the antenna outside the enclosure with a short coax cable.

Besides, it's low power ;)

Didier KO4BB


On March 15, 2016 2:10:21 PM CDT, Poul-Henning Kamp  wrote:
>
>In message
>
>, Pete Lancashire writes:
>
>>http://linuxgizmos.com/beefed-up-beaglebone-black-clone-launches-on-indiegogo/
>
>I'm not sure I'd want a WLAN transmitter inside my 5370...
>
>-- 
>Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
>p...@freebsd.org | TCP/IP since RFC 956
>FreeBSD committer   | BSD since 4.3-tahoe
>Never attribute to malice what can adequately be explained by
>incompetence.
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[time-nuts] Thunderbolt monitor kits available doon

[Didier Juges]

Finally, by popular demand, another batch of Thunderbolt Monitors are coming...

Check http://www.ko4bb.com/getsimple/index.php?id=the-thunderbolt-monitor-kit



Didier KO4BB

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Re: [time-nuts] Lady Heather Server On Raspberry Pi 2 Model B?

[Didier Juges]

For those who want to remotely monitor their Thunderbolt, I am getting ready to 
put out a new Thunderbolt kit with WiFi.

With the WiFi option, it is a server compatible with LadyHeather in client mode 
over the net.

The prototype is working, I am ready to buy the production hardware, which 
should be available in a couple of months.

Didier KO4BB


On January 10, 2016 4:06:51 PM CST, Ben Hall  wrote:
>On 1/10/2016 1:06 PM, Mark Sims wrote:
>>> Porting the GUI client to anything else would be a fair bit of
>>> work, though.
>> Not all that much work.  There are only a few routines that would
>> need to be supplied for screen, mouse, and serial I/O.
>
>Hi Mark and all,
>
>How much *skill* is needed to do a port?  I'd love to have a Nortel 
>NTBW50AA / NTGS50AA GPSDO source (while the Z3801 continues to work, it
>
>does fail self-test), but the thought of having yet another Windows PC 
>going in the shack gives me hives.  (okay, maybe not that bad, but...)
>
>A Raspberry Pi on the other hand doesn't take up much space, has the 
>ability to be remote controlled easily, and would probably lead to me 
>purchasing one of the Nortel units.
>
>So I'd love to see a port, but given that my last programming effort
>was 
>FORTRAN 77 and Windows basic (although I'm learning C for the MSP430 at
>
>the moment) I wonder if I've got anywhere near the skills to do it...
>
>thanks much and 73,
>ben, kd5byb
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Re: [time-nuts] Einstein Special on PBS

[Didier Juges]

Wow. So elegantly simple explanation, thanks John!

On November 27, 2015 2:54:51 PM CST, John Miles  wrote:
>So, here's how I finally grokked this stuff.  c, the speed of light in
>a vacuum, is often spoken of as a "speed limit" that nothing can ever
>exceed.  That's a bad way to put it, and people who have expressed it
>that way in popular science writing for 100 years should feel bad.  
>
>Instead, the way to visualize relativity is to realize that c is the
>*only* speed at which anything can travel.  You are always moving at
>300,000,000 meters per second, whether you want to or not.  But you're
>doing it through all four dimensions including time.  If you choose to
>remain stationary in (x,y,z), then all of your velocity is in the t
>direction.  If you move through space at 100,000,000 meters per second
>in space, then your velocity in the t direction is 283,000,000 meters
>per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)   
>
>It doesn't make sense to speak of moving a certain number of "meters"
>through time, so your location in time itself is what has to change. 
>You won't perceive any drift in your personal timebase when you move in
>space, any more than you will perceive a change in your location
>relative to yourself.  ("No matter where you go, there you are.")  But
>an independent observer will see a person who's moving at 100,000,000
>meters per second in x,y,z and 283,000,000 meters per second in t.  
>They see you moving in space, in the form of a location change, and
>they also see you moving in time, in the form of a disagreement between
>their perception of elapsed time and your own.   
>
>Likewise, if you spend all of your velocity allowance in (x,y,z), your
>t component is necessarily zero.  Among other inconvenient effects that
>occur at dt/dt=0, you won't get any closer to your destination, even
>though your own watch is still ticking normally.  Particles moving near
>c experience this effect from their point of view, even while we watch
>them smash into their targets at unimaginable speeds.
>
>This is special relativity in action.  The insight behind general
>relativity is twofold:  1) movement caused by the acceleration of
>gravity is indistinguishable from movement caused by anything else; and
>2) you don't even have to move, just feel the acceleration.  That
>second part was what really baked peoples' noodles.  It is what's
>responsible for the disagreement between the two 5071As.
>
>-- john, KE5FX
>Miles Design LLC
>
>> Hi Mike,
>> 
>> The time rate does remain the same - at the device.  The problem is
>the idea
>> that it is the hyperfine transitions that determine the time...
>
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Re: [time-nuts] beaglebones, time, web services

[Didier Juges]

I have been working on and off on that kind of project for a while.
One type of issue you have when trying to control hardware from a web page is 
that any hardware access from a web server poses many issues, such as 
permissions and the fact that web servers are basically stateless and many are 
multitasking. 
What happens if your web page (or the python script behind it) tries to send 
data on a serial port (for instance) and another request for the same thing 
comes along?

The current approach I am using is to have a separate process that maintains 
the device status in files that be easily accessed by the web server, so that 
simple status requests can be serviced immediately without needing to query the 
device each time, and use a fifo to pipe commands between the web page script 
and the process. The process is the only one that talks to the hardware, so 
there is no contention.

On the client side, you can use Ajax to keep the web page updated with fresh 
data without reloading everything each time. It is JavaScript, but there is not 
too much of it. That part is relatively easy, unless you want to make it really 
pretty. In that case, it takes a different set of skills (art major with CSS 
experience...)

Here is a demo:

http://www.ko4bb.com/AjaxDemo/x-web.html

The back end of that runs on php, but it could be python just the same.

Obviously failing the pretty test :)

Didier KO4BB


On July 4, 2015 8:13:06 AM CDT, Jim Lux jim...@earthlink.net wrote:
I've got a project I'm working on to make a sophisticated sundial with 
moving mirrors.  I've got a batch of Arduinos that move the mirrors to 
the appropriate places, given the current sun angle, etc.

I've got a beaglebone that runs some python code to calculate sun angle

based on time

The beaglebone will have a GPS feeding it to get time.

BUT now, I'd like to add a web interface, so that it can be manipulated

by a mobile device using a browser.

One way I can think of is to run some sort of limited web server. there

are a couple that come with the beaglebone, including the python 
simplehttpserver.

But I'm sort of stuck on the interface between the webserver and the 
other code running.

I've done this kind of thing where the one task goes out and updates 
files in the tree that's being served by the web server, and that works

fine for status display kinds of things that don't update very 
quickly. It's also nicely partitioned.

but I want to be able to change the behavior of the system (e.g. by 
having the server respond to a PUT or something)

Is the best scheme to go in and modify the webserver code to look for 
specific URLs requested, and then fire off some custom code to do what
I 
want?

I'm not particularly interested in javascript, and would prefer python.


Or are there libraries that make this more cookbook? (the little 
getting started with beaglebone book talks about flask)

There's quite a few websites out there where someone has done some sort

of home automation, but they tend to be a bit light on the analysis
of 
pros and cons of implementation architectures: I built X using Y and Z

and it sort of works.


Actually, along a similar line.. my solar position code isn't very 
pretty (it's sort of replicating some code I wrote in Basic a long time

ago, with some changes from stuff I cribbed from ccmatlab).  If someone

knows of a python package that just does this, I'd love to hear about

it.  Either Az El, or X,Y,Z in ECI or ECF would do.



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Re: [time-nuts] Manuals heading for the dumpster

[Didier Juges]

I think the main contributor to the death of their business is that new 
equipment comes with usually worthless manuals, and even for those who have 
somewhat better manuals, the instruments are still not repairable by the 
amateurs.

I realize that free sites (like mine) probably did not help, but the 
handwriting was on the wall a long time ago and it is unfortunate.

Didier KO4BB

PS: I intent to keep my site up as long as I can afford it, and if someone 
comes up with a dumpster's worth of scanned manuals, I will find the disk space 
for it, but unfortunately, I can't afford to buy any of it myself.

On May 29, 2015 11:01:12 AM CDT, Gregory Muir engineer...@mt.net wrote:
To all,

Am not sure if any news of this has been posted in prior times or not
but will pass it along just in case.

Manuals Plus (http://www.manualsplus.com/) will be closing its doors
the middle of June.  The proliferation of available PDF documents
available plus the increasing number of other sellers on eBay has
reduced their business to a point where they cannot afford to remain
alive.  As a result, they are going to close up shop.

No one has stepped in to assume the manual stock that they currently
have so it has been decided that when things cease, all of their stock
that hasn't sold will hit a large roll-on dumpster and head either for
the dump or a recycler.

They are entertaining offers for manuals at this point.  Becky, the
main contact at MP is the one to talk to,  She is very amiable to
making deals on manuals.  I have been stocking my files with some very
unobtainable legacy manuals for great prices far below the ones asked
on eBay or from other dealers.

It's a shame to see such a resource disappear.  But it is even worse to
see thousands of legacy manuals get destroyed in the process.  MP has
been one of my main sources for many rare manuals from many equipment
manufacturers over the years.

It is realized that the majority of their manual stock pertains to test
equipment but there may be that one odd thing you are looking for that
they have.  One comment is that their search engine is somewhat
primitive.  I produces results from manufacturer names or equipment
model numbers only.  Try several variations of model numbers (such as
removing suffixes, etc) to see if other manuals will appear.

Greg
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Re: [time-nuts] HP 10544A repair

[Didier Juges]

The quarantine is officially over (for this week :)

Thanks for the uploads

Didier KO4BB

PS: I am now trying to move the manuals and equipment specific docs out of the 
GPS Timing folder into the manufacturer's folders. I realize it may be less 
convenient for those who are only interested in timing information, but it 
makes the overall organization of the site easier for me and (I hope) for a 
majority of users.
Until that is complete, you can find HP timing info in two folders, the GPS 
Timing folder and in the HP Agilent folder for instance. The search works 
through the entire site, so finding stuff should not be harder.
As I am sure most of you have noticed, I have implemented a Content Management 
System. The main reason was to make the site easier to manage. A side benefit 
is to keep my Google rankings up since the CMS is mobile friendly and now 
Google ranks down the sites that are not. I am sorry for those who lament the 
loss of Comic Sans... The old site is still there, the old links still work but 
the old pages won't be maintained. After a while, they will go away.


On April 27, 2015 4:14:07 AM CDT, Charles Steinmetz csteinm...@yandex.com 
wrote:
That reminds me -- years ago I cleaned up, corrected, and annotated a 
copy of the HP 10544 schematic.  I dug it up and just posted it to 
Didier's site (http://www.ko4bb.com/manuals/).  When it comes off 
quarantine, you can find it by searching for HP 10544A schematic 
corrected and annotated.

Best regards,

Charles

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Re: [time-nuts] Modern HW replacement for ATOM based NTP server?

[Didier Juges]

Is the new RPi2 any different in that regard?

On April 7, 2015 8:17:12 AM CDT, Daniel Mendes dmend...@gmail.com wrote:

Internally the rPI is a ver awkward beast: the CPU is connected to a 
GPU, and the GPU is connected to the GPIOs... so lots of jitter and
latency.

It was designed to be a video decoder... the CPU is there for testing 
and housekeeping. It works, surelly, but it´s not designed to have low 
latency and jitter.

Daniel

On 07/04/2015 09:39, Hal Murray wrote:
 albertson.ch...@gmail.com said:
 In terms of performance, ARM based credit card sized computers do
well if
 you can get the PPS to the general purpose I/O pin that interrupts
on an
 edge.  the Pi can't do that the BeagleBone Black can and it sell for
$45.
 What/why can't the Pi do?  I have one handy that is processing a PPS
on a
 GPIO pin.

 David Taylor has a web page with all the fine print on how to set it
up.
 (Thanks.)







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Re: [time-nuts] Seeking Racal 9480 Manuals

[Didier Juges]

Not at home right now but if you send me an email with what needs to be done, 
I'll be glad to do it.

Didier KO4BB


On March 12, 2015 6:54:06 PM CDT, Dan Rae dan...@verizon.net wrote:
On 3/12/2015 1:47 PM, George Atkinson wrote:
 Done.

But you might want to get Didier to correct the file names, they show
as 
9840...

Dan
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Re: [time-nuts] 50 ohm driver

[Didier Juges]

Martyn, if you only need 1Hz, I recommend you use a MOSFET driver like the
MIC4420 series or the UCC27531, powered from 10V with a 50 ohm output
resistance. These parts have several A current capability, 18V or more max
VCC and are designed to drive capacitive loads (large MOSFET gate
capacitance). It would not work at 10MHz (because of propagation delay and
self heating), but at lower frequencies, they work very well.
The UCC27531 has lower propagation time and comes in an SOT-23 package, the
others are available in DIP-8 and SO-8.

Didier KO4BB

On Thu, Mar 5, 2015 at 3:59 PM, Martyn Smith mar...@ptsyst.com wrote:

 Hello,
 Thanks for all the feedback.
 I should explain.  I have an existing product that uses the 74AC14.
 I have a customer who needs 5V into 50 ohm and can’t wait for the
 competitive product that does this, or for me to re-design my unit.
 So I have been looking for a quick fix.
 I got excited when I found the SN74AS1004AD which has the exact same
 function and pin out but delivers 48 mA per channel.
 While one output did give me 0-3.0 V into 50 ohm, combining them, as we do
 for the 74AC, actually produced worse results.
 Maybe the output driver is different.
 Anyway I’ve managed to get 0-4.8V by jacking up the supply voltage to 5.7
 V for the 74AC14 and making the three 47 ohm resistors 0 ohm.
 Risetime  4 ns.
 Basically to ideas that TimeNuts gave me.
 I’m just worried the IC may die after a few months.  But since the
 customer will only use it at 1 Hz and hopefully 50:50 duty, or less, I hope
 to get away with it.
 Of course if he removes the input and the outputs are on high, then that
 may be a problem.
 BTW, the reason he wants this high voltage is because he is driving a very
 long cable from the distribution  amp to the actual receiver.
 Anyway I have an IC on test for a week to make sure it lasts.
 Regards
 Martyn


 Today's Topics:

1. Re: 50 ohm Driver (Bob Albert)
2. Re: 50 ohm Driver (Graham / KE9H)
3. Re: 50 ohm Driver (Tom Van Baak)
4. Re: 50 ohm Driver (Hal Murray)
5. Re: 50 ohm Driver (Dan Kemppainen)
6. Re: Trimble Thunderbolt NMEA ? (Didier Juges)
7. Re: 50 ohm Driver (Bob Camp)
8. Re: 50 ohm Driver (Charles Steinmetz)
9. Re: new tdc from Texas (Angus)
   10. Re: new tdc from Texas (Attila Kinali)


 --

 Message: 1
 Date: Wed, 4 Mar 2015 16:49:11 + (UTC)
 From: Bob Albert bob91...@yahoo.com
 To: Discussion of precise time and frequency measurement
 time-nuts@febo.com
 Subject: Re: [time-nuts] 50 ohm Driver
 Message-ID:
 1276775018.2671439.1425487751520.javamail.ya...@mail.yahoo.com
 Content-Type: text/plain; charset=UTF-8

 5V into 50 Ohms means 100 mA.  Perhaps you need a medium power transistor
 amplifier or opamp.
 Bob


  On Wednesday, March 4, 2015 6:09 AM, Martyn Smith mar...@ptsyst.com
 wrote:


 Hello,

 A quick question.

 My output driver for a simple amplifier.

 I use three gates (in parallel with resistors) from a 74AC14 to give me
 about 0-3.2V into 50 ohm.

 I want to have a driver that gives me a full 0-5V (at least 0-4.5V) swing
 into 50 ohms.

 Can anyone recommend an IC that can delivery this.

 But it needs to have similar jitter performance to the 74AC14.

 I use it up to 10 MHz.

 Best Regards

 Martyn

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 and follow the instructions there.




 --

 Message: 2
 Date: Wed, 4 Mar 2015 12:16:02 -0600
 From: Graham / KE9H ke9h.gra...@gmail.com
 To: Discussion of precise time and frequency measurement
 time-nuts@febo.com
 Subject: Re: [time-nuts] 50 ohm Driver
 Message-ID:
 capyj-yxrlkw6y-poglqwjss+mehm6ifc+etyb-mcczkhjpw...@mail.gmail.com
 Content-Type: text/plain; charset=UTF-8

 Building on top of John's comments, if you are using a logic gate, look at
 the
 maximum output (pull up) current per pin, set the series resistor so that
 this
 current is not exceeded into a short, then also see if there is a maximum
 total
 current draw for all gates combined, or some power input pin, and do not
 exceed
 that.

 You can also look at switching the termination resistor from a simple 50
 Ohm
 resistor to ground, to a Thevenin load, which is 100 Ohms from +V to the
 load point,
 and another 100 Ohm resistor from the load point to ground. This way you
 still have a 50 Ohm termination, but only draw one half the DC current.
 In the event of no input, the receiver voltage will go to half scale. Make
 sure your system will not misbehave when this happens.

 Alternate driver is to use a video line driver with sufficient bandwidth.

 --- Graham / KE9H

 ==

 On Wed, Mar 4, 2015 at 7:54 AM, John Ackermann N8UR j...@febo.com wrote:

  One comment on the parallel AC gate approach.  It may not be directly
  applicable to Martyn's issue, but there is a common

Re: [time-nuts] Pinout of FEI 5680B

[Didier Juges]

I have added this info to the wiki:

http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:fe5680a_pin-out

Thanks

Didier KO4BB


On Sat, Feb 21, 2015 at 2:25 PM, Bob Camp kb...@n1k.org wrote:

 Hi

 Just so it goes into the archives. Here’s the pinout for the FE-5680B with
 a 15 pin connector on it.

 Marking shows as part number 2616000-51604

 Pin Function
 1   = +15V power in (likely the same spec as 5680A)
 2   ground
 3   +5  power in (for some, but not this one)
 4   ground
 5   RF out (for some, but not this one)
 6   spare
 7   ground
 8   0 to 5V(?) analog tune in (for some but not all, I’d
 *guess* not for this one)
 9   factory use only
 10  ground
 11  1 pps out (for this one, but not all) lvttl
 12  lock indicator (open collector)
 13  reset (lvttl input, active high)
 14  serial in (lvttl)
 15  serial out (lvttl)

 Yes, this is in answer to a question Skip asked back in 2009. Replying to
 that thread might
 cause something to explode somewhere :)

 They seem to be up on eBay for $45 at the moment, along with the info
 above. No idea if this batch
 is any good. I haven’t bought any.  I’m sure the question of pinout will
 come up again in about
 2 years time. By then the listing and the info will be long gone.

 Bob
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Re: [time-nuts] 50 ohm driver

[Didier Juges]

The MOSFET drivers are limited in the max frequency they can operate at without 
burning. At 1 Hz it is of course not a problem but at 10MHz it most definitely 
would be.

Since Martin did not originally say at what frequency he wanted to operate, it 
was most relevant.

MOSFET drivers can deliver a few nS edges while driving significant capacitance 
at several hundred kHz. They can be very useful for low frequency clock 
drivers.

Didier KO4BB



On March 7, 2015 10:10:45 AM CST, Graham / KE9H ke9h.gra...@gmail.com wrote:
The question is not the frequency, but the edge rate.  For a 1 PPS
signal,
how fast a rise time do you need?  Do you want to know the time of the
edge to 1/100 second? one microsecond? one nano-second? A few
pico-seconds?

If you want to know the time of the edge to one nano-second, then you
need a driver that can push sine-waves at over a few GHz. Not 10 MHz.

--- Graham / KE9H

==

On Sat, Mar 7, 2015 at 7:58 AM, Didier Juges shali...@gmail.com
wrote:

 Martyn, if you only need 1Hz, I recommend you use a MOSFET driver
like the
 MIC4420 series or the UCC27531, powered from 10V with a 50 ohm output
 resistance. These parts have several A current capability, 18V or
more max
 VCC and are designed to drive capacitive loads (large MOSFET gate
 capacitance). It would not work at 10MHz (because of propagation
delay and
 self heating), but at lower frequencies, they work very well.
 The UCC27531 has lower propagation time and comes in an SOT-23
package, the
 others are available in DIP-8 and SO-8.

 Didier KO4BB

 On Thu, Mar 5, 2015 at 3:59 PM, Martyn Smith mar...@ptsyst.com
wrote:

  Hello,
  Thanks for all the feedback.
  I should explain.  I have an existing product that uses the 74AC14.
  I have a customer who needs 5V into 50 ohm and can’t wait for the
  competitive product that does this, or for me to re-design my unit.
  So I have been looking for a quick fix.
  I got excited when I found the SN74AS1004AD which has the exact
same
  function and pin out but delivers 48 mA per channel.
  While one output did give me 0-3.0 V into 50 ohm, combining them,
as we
 do
  for the 74AC, actually produced worse results.
  Maybe the output driver is different.
  Anyway I’ve managed to get 0-4.8V by jacking up the supply voltage
to 5.7
  V for the 74AC14 and making the three 47 ohm resistors 0 ohm.
  Risetime  4 ns.
  Basically to ideas that TimeNuts gave me.
  I’m just worried the IC may die after a few months.  But since the
  customer will only use it at 1 Hz and hopefully 50:50 duty, or
less, I
 hope
  to get away with it.
  Of course if he removes the input and the outputs are on high, then
that
  may be a problem.
  BTW, the reason he wants this high voltage is because he is driving
a
 very
  long cable from the distribution  amp to the actual receiver.
  Anyway I have an IC on test for a week to make sure it lasts.
  Regards
  Martyn
 
 
  Today's Topics:
 
 1. Re: 50 ohm Driver (Bob Albert)
 2. Re: 50 ohm Driver (Graham / KE9H)
 3. Re: 50 ohm Driver (Tom Van Baak)
 4. Re: 50 ohm Driver (Hal Murray)
 5. Re: 50 ohm Driver (Dan Kemppainen)
 6. Re: Trimble Thunderbolt NMEA ? (Didier Juges)
 7. Re: 50 ohm Driver (Bob Camp)
 8. Re: 50 ohm Driver (Charles Steinmetz)
 9. Re: new tdc from Texas (Angus)
10. Re: new tdc from Texas (Attila Kinali)
 
 
 
--
 
  Message: 1
  Date: Wed, 4 Mar 2015 16:49:11 + (UTC)
  From: Bob Albert bob91...@yahoo.com
  To: Discussion of precise time and frequency measurement
  time-nuts@febo.com
  Subject: Re: [time-nuts] 50 ohm Driver
  Message-ID:
  1276775018.2671439.1425487751520.javamail.ya...@mail.yahoo.com
  Content-Type: text/plain; charset=UTF-8
 
  5V into 50 Ohms means 100 mA.  Perhaps you need a medium power
transistor
  amplifier or opamp.
  Bob
 
 
   On Wednesday, March 4, 2015 6:09 AM, Martyn Smith 
 mar...@ptsyst.com
  wrote:
 
 
  Hello,
 
  A quick question.
 
  My output driver for a simple amplifier.
 
  I use three gates (in parallel with resistors) from a 74AC14 to
give me
  about 0-3.2V into 50 ohm.
 
  I want to have a driver that gives me a full 0-5V (at least 0-4.5V)
swing
  into 50 ohms.
 
  Can anyone recommend an IC that can delivery this.
 
  But it needs to have similar jitter performance to the 74AC14.
 
  I use it up to 10 MHz.
 
  Best Regards
 
  Martyn
 
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  To unsubscribe, go to
  https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
  and follow the instructions there.
 
 
 
 
  --
 
  Message: 2
  Date: Wed, 4 Mar 2015 12:16:02 -0600
  From: Graham / KE9H ke9h.gra...@gmail.com
  To: Discussion of precise time and frequency measurement
  time-nuts@febo.com
  Subject: Re: [time-nuts] 50 ohm Driver
  Message-ID:
 
capyj-yxrlkw6y-poglqwjss+mehm6ifc+etyb-mcczkhjpw...@mail.gmail.com
  Content-Type

Re: [time-nuts] Trimble Thunderbolt NMEA ?

[Didier Juges]

The code is in C and Silabs has small dev kits (Toolsticks) that cost $10 to 
which you need to add $18 for the programming dongle. A little more expensive 
than an Arduino, or less, depending on where you buy it...

To that you need to add a MAX232 (or two serial-TTL adapters at $4 each or so 
on ebay) and you are in business.

Total cost about the same as a dedicated GPS receiver with antenna and NMEA 
output. Choose your poison :)

Didier KO4BB


On March 3, 2015 10:23:56 PM CST, Chris Albertson albertson.ch...@gmail.com 
wrote:
Is the code in C?  If so I bet it would run on some development board. 
No
need to make custom PCBs.

On Tue, Mar 3, 2015 at 5:00 AM, Didier Juges shali...@gmail.com
wrote:

 Tim,

 It shouldn't be too hard to modify the code for my Thunderbolt
monitor to
 make it into a TSIP-NMEA converter. The last version of the kit has
a uC
 with two serial ports. I m out of the kits at the moment but I have a
few
 spare boards left over.


-- 

Chris Albertson
Redondo Beach, California
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Re: [time-nuts] Trimble Thunderbolt NMEA ?

[Didier Juges]

Tim,

It shouldn't be too hard to modify the code for my Thunderbolt monitor to make 
it into a TSIP-NMEA converter. The last version of the kit has a uC with two 
serial ports. I m out of the kits at the moment but I have a few spare boards 
left over.

Don't have time to write the code at the moment, but I have released the source 
code for the kit.

Didier KO4BB


On March 2, 2015 5:06:21 PM CST, Tim t...@skybase.net wrote:
On 3/03/2015 4:33 AM, Didier Juges wrote:
 Tim,

 NMEA is normally used for navigation. It would seem unlikely that
anyone would want to use a Thunderbolt for navigation. Can you
elaborate on what you are trying yo do?


Hi Didier,

I' building a multi frequency beacon based on QRP-labs U3 beacon kit.
It 
has the ability to discipline its oscillator with a PPS input and,
using 
NMEA input, set and maintain time and location for exact control of
WSPR 
and OPERA modes of operation.

As it currently only accepts NMEA input I was wondering there was a way

to get NMEA out of a thunderbolt. I've lodged an RFE with the developer

to add TSIP support to the U3, but I don't think that's going to happen

anytime soon.

I'd rather use the Thunderbolt as the time and PPS source since its way

more accurate than the LEA-M8FGPS module that optionally comes with the
kit.

I'd like to use the U3 as the basis of beacons all the way to 10GHz and

the Thunderbolt is a superior device for locking such things and 
supplying the base 10Mhz to lock the appropriate LO's.

thanks

Tim

-- 
VK2XAX :: QF56if23 :: BMARC :: WIA :: AMSATVK

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Re: [time-nuts] Trimble Thunderbolt NMEA ?

[Didier Juges]

Tim,

NMEA is normally used for navigation. It would seem unlikely that anyone would 
want to use a Thunderbolt for navigation. Can you elaborate on what you are 
trying yo do?

Didier KO4BB

On February 25, 2015 10:11:08 PM CST, Tim t...@skybase.net wrote:
Hi all,

Is there a way to get NMEA instead of TSIP out of a Thunderbolt ?

Failing that, is there some translating device that I can insert
between 
the Thunderbolt and another device that is expecting NMEA ?

thanks

Tim

-- 
VK2XAX :: QF56if23 :: BMARC :: WIA :: AMSATVK

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Re: [time-nuts] SR620 question

[Didier Juges]

Simply pasting the link did not work, but it was close enough :-)

The links that include an IP address (like 81.226.54.139 below) only work until 
midnight EST, then they are cleared.

It is easy enough (but not necessarily intuitive) to go to the manuals page and 
search again for the document.

I am trying to come up with a scheme that will create a permanent link. Bear 
with me a little longer...

Didier KO4BB


On January 28, 2015 7:41:59 AM CST, Gerhard Hoffmann dk...@arcor.de wrote:
Am 28.01.2015 um 00:23 schrieb Magnus Danielson:

 It locks it up with a PLL. See page 9 in PDF below, smack in the 
 middle is the input circuit and PLL.

 This page also gives you all the hints of how to wire in a better 
 oscillator if you wish.

 2 I have seen that the manual has a parts list and references the 
 circuit
 diagrams, but they are not included in the pdf. Are the circuits 
 somewhere
 out there?


http://www.ko4bb.com/manuals/81.226.54.139/SR620_Universal_Time_Interval_Counter_Schematics.pdf



Simply pasting the link did not work, but it was close enough :-)

Thanks, also to Charles!

After Bob's comment, I have ordered it with the oven. Should be here 
in 
.de in a good week.

 My 5370A has become so unreliable that it needs replacement.

 What issues do you see?

Erratic blinking of the display, probably column drivers, but not only,
 
bad switches that
seem to stick now  then..  For some time, it was enough to remove and 
re-insert the
boards, but no more. I don't have the time now to look deeply into it.
All would not be lost.  It has a nice 10811.

regards, Gerhard
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Re: [time-nuts] D term (was no subject)

[Didier Juges]

Maybe we are getting a little off-topic here, but a very long time ago I
was dealing with industrial ovens used to braze ceramics used to make
microwave tubes.
It was very difficult to maintain the precise temperature ramp up and down,
particularly as the oven was not always loaded the same way.

In order to automatically compensate for different oven loading (and
ambient conditions), the controller injected a very low level random
noise over the temperature setting and by analyzing how that noise was
filtered by going through the oven, was able to determine the response of
the oven itself and from that optimize the PID terms in real time as a
function of the load. This was in the early 80's. It was pretty hot stuff
then, even for an oven :)

Didier KO4BB


On Sun, Jan 25, 2015 at 8:12 PM, Jim Lux jim...@earthlink.net wrote:

 On 1/25/15 1:30 PM, WarrenS via time-nuts wrote:


 I second  Poul-Henning Kamp's comments concerning D-terms,
 (mostly) as done in the TBolt and likely other GPSDOs.




 Bear in mind that a PID loop is basically a fairly simple control loop
 that is easily susceptible to linear analysis.
 They're simple to implement with analog controls, they're simple to
 analyze, and for a whole lot of applications, they'll work just fine.

 And there's decades, if not centuries, of experience with P, PI and PID
 controllers in a practical sense.  A lot of people know how to *tune* the
 parameters based on observed system dynamics.


 But for a lot of systems:ones where there are significant nonlinearities
 and/or time delays and/or saturation/limiting effects a PID loop might not
 be a good choice.  (for instance, if you're doing a closed loop position
 control with a stepper motor as the actuator, with a small motor and a big
 heavy load, with low friction...)

 For myself, I am seduced by the idea of a control system that builds and
 adjusts a model of the system being controlled, and then derives the needed
 control inputs from inverting that model (whether arithmetically, or by
 some clever algorithmic means).

 For instance, a PID controller doing temperature control doesn't have a
 *good* way of incorporating side information like the outside temperature.
 There's all kinds of schemes for doing this (double loops, extra terms,
 etc.)



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Re: [time-nuts] (no subject)

[Didier Juges]

Without a D term, PI loops can be unstable when the gain (P) is increased. If 
you will, with a large error, the correction will itself be large and as the 
system corrects itself, it may overshoot the target value, going into a low (or 
high if you really blew it) level oscillation around the target value. The D 
term slows it down just enough and minimizes that overshoot while maintaining a 
high gain (low steady state error) and a fast response.

Didier KO4BB




On January 24, 2015 8:05:38 PM CST, Bob Camp kb...@n1k.org wrote:
Hi

A classic control loop in it’s simplest form has only one term. That is
often referred to as a proportional term. When the control signal (or
error) changes by A the output changes by A times that term. Often in
shorthand notation this term is refereed to as a P term. 

The next thing that some people add to a control loop is an integrator.
It looks at the control signal (or error) has a constant offset of A,
the integrator sums up the A’s. The output of an integrator would
eventually go to infinity with a constant control input (or error) into
it. This term is often referred to as an I term. 

Lastly people add a term to the control loop that responds to the rate
of change in the control signal (or error). The faster the change, the
bigger this signal gets. This is commonly refereed to as a Derivative
term. In shorthand it’s talked about as the D term. 

The net result is a three element control loop running what’s called a
PID algorithm . 

The P and I can also be described by a time constant and a damping.
That’s what the Trimble software lets you do. The implication is that
it’s just a PI loop. In fact it appears to be a PID loop and you can’t
get at the D term. 

For a much more clearly worded explanation of all this, there’s

http://en.wikipedia.org/wiki/PID_controller

Bob
 
 On Jan 24, 2015, at 6:35 PM, Cash Olsen radio.kd5...@gmail.com
wrote:
 
 Bob,
 
 I am relatively new to the list and still learning the jargon and
 concepts. You wrote: There does appear to be a D in the TBolt loop.
 For what ever reason, that’s not a changeable value. The D does scale
 with the time constant.
 
 Could you or one of the other members elaborate on the what is meant
 by D above. Does it have anything to do with a flat spot in the
 loop?
 
 -- 
 S. Cash Olsen KD5SSJ
 ARRL Technical Specialist
 
 Message: 10
 Date: Sat, 24 Jan 2015 09:18:15 -0500
 From: Bob Camp kb...@n1k.org
 To: Discussion of precise time and frequency measurement
time-nuts@febo.com
 Subject: Re: [time-nuts] Questions regarding tuning Thunderbolt with
LadyHeather -- GPSDO's
 Message-ID: 6581eb02-9792-432f-b143-25b41fb29...@n1k.org
 Content-Type: text/plain; charset=utf-8
 
 
 There does appear to be a D in the TBolt loop. For what ever reason,
 that’s not a changeable value. The D does scale with the time
 constant.
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Re: [time-nuts] Questions regarding tuning Thunderbolt with Lady Heather -- GPSDO's

[Didier Juges]

This operation is very typical of all of the cell site GPSDO’s. The only
part that is unique to the TBolt is the ability to fiddle the loop
characteristics a bit.

And the fact that the GPS's CPU clock is derived from the 10MHz and
therefore aligned to the PPS so there is no hanging bridge and sawtooth
correction is not required.

I am not aware of any other GPSDO implementing that scheme, which is very
elegant in its simplicity.

Didier KO4BB


On Sat, Jan 24, 2015 at 8:18 AM, Bob Camp kb...@n1k.org wrote:

 Hi

 Maybe a bit more information, much of it applies to all GPSDO’s :

 The TBolt first goes through a process to get the OCXO roughly on
 frequency and to get the PPS approximately aligned. That process is not
 impacted by the time constant and damping. The OCXO goes a bit crazy during
 this process.

 It then starts the phase lock process with a short time constant. As the
 OCXO settles in, it will step out to a progressively longer time constant.
 It does this based on it’s internal estimates of lock quality. Unless you
 are already at maximum time constant and have a good internal estimate,
 changing the time constant has no immediate impact. On most GPSDO’s and
 with most OCXO’s under most conditions, the step out process takes days or
 weeks.

 The damping number does impact the performance in the maximum time
 constant mode. It may be scaled as the time constant is changed.

 There does appear to be a D in the TBolt loop. For what ever reason,
 that’s not a changeable value. The D does scale with the time constant.

 When in lock mode, the TBolt is a PLL and not a FLL. As the “phase in”
 (the pps from the gps) moves, the frequency of the OCXO will change to keep
 the “phase out” (PPS output) aligned. As the unit is running, it keeps
 track of the average DAC value that puts the OCXO on frequency. Since it’s
 a PLL, that number may or may not be the last instantaneous value of the
 DAC when it goes into holdover. Since it’s running a PLL, the PPS output
 will indeed be the best value, so no correction is needed there when it
 goes into holdover (not quite true, but that is the assumption made).

 This operation is very typical of all of the cell site GPSDO’s. The only
 part that is unique to the TBolt is the ability to fiddle the loop
 characteristics a bit.

 Bob

  On Jan 23, 2015, at 10:58 PM, Skip Withrow skip.with...@gmail.com
 wrote:
 
  Hello Nuts,
  I have been playing a bit tuning a Thunderbolt with Lady Heather and now
  have more questions than answers.  The collective time-nut brain would be
  appreciated.
 
  1. Using the '' command I can change the damping and time constant in
 LH.
  Are these values immediately transferred to the TB?
 
  2. Do I have to use the LH 'e' command to permenantly save new damping
 and
  time constant values to the TB?
 
  3. After using the '' and 'e' command the lock-in behaviour of the TB
 does
  not seem to change.  Is this normal behaviour?  Is one set of values used
  when locking and the adjusted values used once it is phase locked?
 
  4.Is there some way to read out the values stored in the TB?  When I use
  the 'e' command on the TB, change values in LH, then restart LH and the
 TB
  I see the last values given to LH, and not what I thought was saved with
  the 'e' command.
 
  5. If the TB is placed in hold mode and the DAC set to 0.0 volts it
  actually goes to 0.2 volts (min is at -5, max is at +5, and iv is 0.0
 which
  it actually starts at on power up).  Anyone know why?
 
  Thanks in advance for any guidance!
  Regards,
  Skip Withrow
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Re: [time-nuts] GPS leap second pending (TBolt/Heather)

[Didier Juges]

Re: Note that this is not a GPS problem, nor a Trimble problem. It's just
a problem with user written software.
I agree with Mark's comment. His software makes no attempt to interpret
or correct the information put out by the Thunderbolt, it simply reports
it. My Thunderbolt Monitor does the same thing.
I can imagine a different tool with a different objective doing something
different with good reason, but that is not what Lady Heather does, by
choice rather than by mistake.

It's a problem with user's expectations :)


On Thu, Jan 22, 2015 at 8:05 PM, Mark Sims hol...@hotmail.com wrote:

 Nope,  it's not an error or a problem.
 That column of data is showing a decode of the 16 status bits that the
 Tbolt is providing.The Trimble docs say that bit is a Leap Pending
 bit,  so that is what Heather displays.   It would be wrong to try and
 mask/adjust the report of the receiver's status word.
 Lady Heather is a monitor and display program for Trimble timing
 receivers.  It shows the values that the receiver is reporting (usually to
 the precision that the receiver provides...  think that micro-degree
 temperature value is really that accurate?  I have a lovely bridge that you
 might want to purchase)   But that's what the receiver is sending,  so
 that's what gets displayed.

 -
 Note that this is not a GPS problem, nor a Trimble problem. It's just a
 problem with user written software.
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Re: [time-nuts] Shera VXCO Controller and PCM61P

[Didier Juges]

The MAX5318 is available at Digikey. Not cheap, and not sure if it is
electrically compatible, but it has good specs (not an audio DAC).
And it is in a TSOP package, so can be soldered on a small adapter board

Didier KO4BB


On Fri, Jan 16, 2015 at 1:49 PM, Jerry Pixton jpix...@shentel.net wrote:

 Hello all.

 I am a Freq-nut recently joining the Time-nut list.

 I am putting together the parts for the Shera VXCO controller using the
 AA PCB.

 What are folks using now a days for the Burr-Brown PCM-61P DAC?

 I can not find the Analog Devices AD1861N chip anywhere either. I do see
 the PCM-61P from Asia via eBay. But if there is another solution i might
 prefer that.



 Jerry, W6IHG

 --
 --
 Dr. Jerry R. Pixton, PIXOS Designs
 http://www.shentel.net/pixosdesigns/RadioTuner
 jpix...@shentel.net
 --

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Re: [time-nuts] Current state of optical clocks and the definition of the second

[Didier Juges]

I have a page that illustrates how you can use a delay line and a mixer to 
separately obtain AM and PM

http://www.ko4bb.com/Timing/Phase_Detector

Didier KO4BB


On January 14, 2015 1:19:11 PM CST, Mike Feher mfe...@eozinc.com wrote:
At those low levels, how does one differentiate between phase or AM
noise? Thanks  Regards - Mike 

Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce
Griffiths
Sent: Wednesday, January 14, 2015 1:22 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Current state of optical clocks and the
definition of the second

Although the phase noise when using optical combs to generate Rf
signals is low there is no mention of the am noise.

Bruce

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Re: [time-nuts] Arduino GPIB

[Didier Juges]

Yes, you can get an Arduino R3 on eBay for $4 with shipping...

The GPIB connector will cost you more!

Didier KO4BB


On January 12, 2015 8:45:12 AM CST, paul swed paulsw...@gmail.com wrote:
That certainly is a hack. But its something I have often thought about
and
never did. He is right its really a one instrument interface as it
doesn't
have the buffers to drive the load of multiple instruments.
But heavens that has to be a really cheap interface for a bit of
soldering
effort. My type of effort. :-)
Regards
Paul.
WB8TSL

On Sun, Jan 11, 2015 at 11:57 PM, Joseph Gray jg...@zianet.com wrote:

 I thought everyone here would find this of interest. I stumbled
across it a
 few days ago on the 'net. It is a Prologix GPIB-USB compatible made
with an
 Arduino Uno.



http://egirland.blogspot.com/2014/03/arduino-uno-as-usb-to-gpib-controller.html

 Like on his web site, I just took a cheap GPIB cable, cut off about
12
 inches and shoved the wires into the socket holes on an Uno. I
uploaded his
 program and did some minor testing so far. BTW, it didn't work the
first
 time due to poor contact. I shoved some pin headers in, after the
wires and
 now it works fine.

 John's Prologix config program works just fine with this cobbled
together
 GPIB adapter. I attached it to my HP 3457A and then ran the demo
program
 that comes with Ulrich's EZGPIB. It is logging data as I type this. I
will
 do more testing with other instruments, as I have time.

 As mentioned on the web page linked above, a few commands are not yet
 implemented, although they appear to be little used commands (except
 perhaps the ++savecfg command). I think I have a way to implement the
++rst
 command using the watchdog timer. For ++savecfg, it shouldn't be too
 difficult to store things in the Arduino EEPROM.

 I have some cheap Arduino Nano's and PCB-mount GPIB connectors on
order. I
 will be making a couple of these Proligix-compatible adapters with
those
 parts, so that they aren't just wires shoved into a board. I'll have
to
 find a small box to house things. I have also ordered some buffer
chips to
 add to the design. Total cost should be under $20 for each adapter.

 The firmware uses a serial baud rate of 115200, which I assume is the
same
 as a real Prologix. I'm going to try some higher baud rates to see
how fast
 the Arduino can push bits without losing them. I understand that with
the
 default 16 MHz clock, non-standard baud rates that are evenly
divisible
 into the clock rate should work even better I'll report back.

 One question about the baud rate - are there any reasons not to
change from
 115200? Since we are simply moving bits through a USB/Serial adapter,
does
 any software really care what the baud rate is, as long as we don't
drop
 any bits?

 Joe Gray
 W5JG
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Re: [time-nuts] June 30 2015 leap second

[Didier Juges]

Hi Tom,

You are correct, but it does not really matter because it will not be 
instantaneous, and for a period of time that is well within the range of human 
perception, the clock will be off by more than you would normally expect.

We have been talking about NTP being able to keep the time to within uS or 
better and this is a system that deliberately introduces an error a million 
times bigger. I am just surprised Time-Nuts would not go nuts about it :)

Didier KO4BB



On January 11, 2015 8:31:12 AM CST, Tom Van Baak t...@leapsecond.com wrote:
 Keep in mind that this system drives you to having pretty bad time
for the
 better part of a whole day, on purpose... I realize that when the

Hi Didier,

The google article never claims the smear spans an entire day. I think
you may be confusing references to the leap smear with a DIY digital
clock someone on the list wanted to build (and they proposed using a
slow 86400 second slew).

The google code is lie(t) = (1.0 - cos(pi * t / w)) / 2.0 and they
are wise not to publish the actual window value, w. If it were me I'd
make it somewhere between a couple of seconds or couple of minutes but
I too would not make it a published or hardcoded constant.

Here's the link again:
http://googleblog.blogspot.com/2011/09/time-technology-and-leaping-seconds.html

Again, I don't know what value they use, or even if they use the same
value from one leap second to the next. If any of you have inside
contacts with google and can find out let me know, off-list.

Regardless, it should be possible to experimentally determine the smear
duration by repeatedly using some google service that returns
time-stamps during the day, hours, minutes, or seconds before and after
June 30. It would make a nice posting for a time nut, or a research
paper for a high school student or undergrad: Experimental Confirmation
of Google's Leap Smear Algorithm.

/tvb

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Re: [time-nuts] June 30 2015 leap second

[Didier Juges]

There are many systems for which the Google fix would not work in the
current state of technology unless implemented by EVERYBODY synchronously.
At least everybody who depends on precise time like banking and financial
systems, let alone the physicists and many others...

Keep in mind that this system drives you to having pretty bad time for the
better part of a whole day, on purpose... I realize that when the
alternative is a system crash, it may sound tempting, but it really is not
a fix, a bandage at most. We have a term for that in French: emplâtre sur
une jambe de bois, cast on a wooden leg.

Didier KO4BB


On Fri, Jan 9, 2015 at 6:57 PM, Henry Hallam he...@pericynthion.org wrote:

 Such slewing solutions are OK for Google.  They wouldn't work well for
 one of the systems I work with, which uses system time to calculate
 the position of a LEO satellite for purpose of pointing a 7.6 meter
 X-band dish.  Half a second of error corresponds to a pointing error
 of 0.5 degrees, well outside the main lobe of the antenna beam.

 Anecdotally yours,
 Henry

 On Fri, Jan 9, 2015 at 2:30 PM, Hal Murray hmur...@megapathdsl.net
 wrote:
 
  t...@patoka.org said:
  1s/24h = 1/86400 which is approximately 12ppm. That means that Aging
 Offset
  could slow down my clock for 1 second if I'll apply the maximum  value
 one
  day ahead (roughly). I need to do some experiments first. ;-)  Its
 looks too
  unreliable for me.
 
  If you do it that way, your clock will be off by a whole second just
 before
  midnight when the leap-second brings it back into sync.  If you tweak
 your
  clock from noon-noon, it will only be off by 1/2 second at midnight when
 the
  sign-bit of the error flips.
 
  --
  These are my opinions.  I hate spam.
 
 
 
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Re: [time-nuts] HP 58503A Com 4 conflict

[Didier Juges]

To add a small dose of additional complexity, Visual Basic 6.0 (and I suspect 
other dev tools of that generation) only support COM ports up to 16. Not as bad 
as 4, but still a problem on occasion.

Didier KO4BB


On January 4, 2015 12:03:05 PM CST, Bob Camp kb...@n1k.org wrote:
Hi

Ok, off into serial land …. 

The GPSDO does not really know or care what port it’s on. It will be
just as happy on port 119 as on port 4.  It (by design) does care about
the baud rate / data bits / parity / stop bits. This is as true with a
USB to serial as with a direct serial card. That’s the good news. Now
for the rest of the news.

If your computer operating system is old enough, you may only *have* 4
com ports. Bad news there = upgrade the computer. Typically this is a
Windows 95 and earlier issue. 

If the software running on the computer is old enough it may only
*know* how to use 4 com ports. Bad news is same = upgrade the software.
Typically this is a Windows 95 era (mid 90’s) issue. 

If the drivers on the serial to usb converter are old enough, they may
only talk as 4 com ports (I’ve never seen this on a modern OS). Same
news = upgrade the driver.

All this relates to Windows. The cutoff times and versions for other
OS’s are a bit more obscure. The same basic details apply. 



If you are running on an XP or newer machine, you should have far more
than 4 com ports available. If you are running any of the newer ( =
past 2000) software to talk to the box, it should be quite happy to
deal with more than 4 com ports. 

My *guess* is that you need a different piece of software. Exactly what
you are doing will determine which one you need. ( = more info
required).

-

 On Jan 4, 2015, at 10:50 AM, James Robbins jsrobb...@earthlink.net
wrote:
 
 My new old HP58503A wants to connect to my PC on Com 1-4.  Other PC
devices are already using those 4 Com ports.  
 
 Is there any way to connect it to a Com port other than one of those
1 to 4?
 
 I currently use an Edgeport USB-to-Serial Converter which works very
well to communicate with the PC and to assign Com ports to my various
GPS units.  But, as far as I know, the chosen Edgeport Com port must
fall within the range of Com ports which for which the device is
designed.
 
 If this has been answered, please point me to the discussion.  Many
thanks.  And, Happy New Year to all, with wishes for a more peaceful
(and timely - couldn't resist) year.

I have this terrible urge to start a calendar thread revolving around
“new” years … so far I’ve resisted the urge. It’s *very* difficult
….arhhh….

Bob

 
 Jim Robbins
 N1JR  
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Re: [time-nuts] Are these PRS10's worth it ?

[Didier Juges]

Check the difference between the LPRO and PRS-10 on John Miles' page:
http://www.ke5fx.com/rb.htm

Assuming these plots are representative of what you are likely to get from
eBay parts (a pretty big assumption right there), the main advantage of the
PRS-10 seems to be at high tau, where the performance of a GPSDRb is mostly
driven by the GPS and PLL anyhow.

Didier KO4BB


On Tue, Dec 30, 2014 at 7:14 AM, Didier Juges shali...@gmail.com wrote:

 You can get a working LPRO for $150 with very reasonable shipping.
 To me, that's a better deal unless you absolutely need the thrill of
 trying to rescue something you knew was bad when you bought it :)


 http://www.ebay.com/itm/Datum-Efratom-Symmetricom-LPRO-10MHz-Rubidium-Oscillator-Tested-5-93-Lamp-Volts-/231436344277?pt=LH_DefaultDomain_0hash=item35e2ae5bd5

 Didier KO4BB


 On Tue, Dec 30, 2014 at 3:15 AM, Poul-Henning Kamp p...@phk.freebsd.dk
 wrote:

 
 In message 54a20c7c.7040...@skybase.net, Tim writes:

 Not knowing much about the PRS10, I'm just wondering if its worth the
 ri$k :)

 You need to hold that price up against the fact that a new PRS10 is $1600.

 --
 Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
 p...@freebsd.org | TCP/IP since RFC 956
 FreeBSD committer   | BSD since 4.3-tahoe
 Never attribute to malice what can adequately be explained by
 incompetence.
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Re: [time-nuts] Downloaded HPs SmartClock / Size of Lucent modules.

[Didier Juges]

Clearly off-topic, but hopefully it will stop here...

The Dell supplies use a 3 wire cable and have a resistor in the power
supply connecting the 3rd wire to ground. The value of that resistor tells
the laptop the current capability of the supply (they have various models
between 3.0 and 4.5A) so that the laptop can determine if it will have
enough current to run. This is mostly applicable when the laptop is plugged
into a docking station, because the current demand is then quite a bit
higher. If the laptop cannot read the resistor value, it may refuse to run
(or ask you to press F1 to force it to run anyhow) The 3rd wire is pretty
small (because it carries negligible current) and it is sometimes the first
one to break. You are then left with a perfectly usable 19.5V power supply
that cannot power a Dell laptop but that is fine for many GPSDO and Rb
oscillators :)

Didier KO4BB


On Sun, Dec 28, 2014 at 10:11 PM, Gerhard Hoffmann dk...@arcor.de wrote:

 Am 29.12.2014 um 00:39 schrieb Dr. David Kirkby (Kirkby Microwave Ltd):

 2)  Can anyone with these $150 two-part Lucent boxes tell me the size of
 them.


 The box itself:  65mm high, 152 mm deep, 244 mm wide

 Front plate:  76 mm high, 274 mm wide

 Just a little bit to big to fit into a 4 HU 19 box ( for both).

 (still doing a night shift on the 5-10MHz doubler, filter  5 chan.
 distrib amp for it.
 Or 4 chan 10 dBm 10 MHz  one 1pps on SMA )


 BTW I once bought a generic chinese power supply as a fallback solution
 for my Dell laptop.
 That turned out not to work because Dells talk to their PS. Nobody else
 seems to do that.
 It now powers my Lucent duo.

 I saw that the PS has an additional 12V input. That may ease the task of
 emergency power
 from a lead or Li-IronPhosphate battery.


 regards, Gerhard

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Re: [time-nuts] LNA and Alias

[Didier Juges]

Bob,

It may not have been Comcast. I had issues (cockpit error on my part) with
the server this morning around the time you wrote your message. It should
be OK now.

However, the new setup is making it more difficult to attach links to
documents because when you click on a document in the Manuals pages, you
get a link that is associated with your IP address, so that link may not
work for other people.

The best way is to simply reference the page name and let people search for
the page for themselves, so that they can get their own link and download
the document.

Overall it is a better method anyhow because I occasionally move things
around to try and keep some organization, so any document is susceptible to
change folder, which will break old links. I rarely change the documents
names though (once they are moved out of the ManualUpload folder), so
searching for the name should always work.

Didier KO4BB


On Mon, Dec 22, 2014 at 8:39 AM, Bob Camp kb...@n1k.org wrote:

 Hi

 At the moment Comcast and ko4bb.com don’t seem to like each other. I
 can’t refer directly to the schematic or the page.

 What you *should* have (assuming 10 MHz inputs for clarity):

 1) The RF inputs go into the mixer from what ever sources you happen to
 want to test. At least one source needs to be high level.

 2) The mixer output goes to an L/C lowpass filter. That filter serves
 several purposes:
 a) It resistively  terminates the mixer at RF (both at 10 and 20
 MHz) in the proper IF impedance
 b) It passes the phase noise information on to the LNA
 c) It rejects all RF going to the LNA

 3) The LNA can be just about anything provided:
 a) It handles the signal levels without overload
 b) It does have low enough noise (that depends a lot on the mixer
 and sources)
 c) It has enough gain
 d) Terminates the mixer in a reasonable resistive impedance at
 audio.

 4) The LNA feeds two things:
 a) Your FFT box
 b) Your DC bias box

 It sounds like the FFT part is working so the DC bias may be an issue. The
 bias box is used to force the two oscillators into quadrature. It forms a
 PLL around the oscillator pair. With the two signals 90 degrees apart your
 mixer has a ~ 0V output. That is the point it is most sensitive to phase
 noise and the least sensitive to AM noise.

 There are lots of ways to do this. Since I can’t see the schematic. Here’s
 one based on an RPD-1 (500 ohm out) mixer:

 One side of the mixer is grounded, the other feeds the filter.

 500 ohms in series with 820 pf to ground as the input to the filter. Some
 sort of coil in the vicinity of 100 uH as the first series lowpass element.
 Next a  470 pf to ground. Then another 100 uH in series. Another 470 pf to
 ground. Another 100 uH in series. Another 470 pf to ground. At this point
 you have a three coil and five capacitor lowpass filter. You should poke it
 into spice to make sure it’s not going to be a problem with your parts. The
 issue is cutoff at the highest frequency you want to look at phase noise.
 You may need to tweak values a bit. The final stage may be overkill
 depending on the quality of your coils. You will always have a tradeoff
 between highest phase noise frequency and lowest RF frequency with this
 setup.

 LNA can be a good audio op-amp. Run it in positive gain mode. Termination
 resistance for the filter is simply set with a resistor to ground. I prefer
 to use 5K for the RPD-1’s.  It gives you a bit more output voltage. It also
 makes the cutoff of the lowpass a bit lower.

 The DC bias box is an op amp plus a pot, resistors and capacitors. You
 need to set the output to the EFC voltage on the OCXO’s. That will vary
 between different parts. One pot is for centering this up. You need to set
 the loop gain, so feedback resistors on the op amp need to be adjusted.
 Some sort of R/C may be used to roll off noise. The cutoff frequency of the
 loop will determine the lowest phase noise frequency you can check unless
 you measure loop dynamics and correct all your data.

 Now that that’s all working, you need to calibrate the setup. Two common
 approaches. Both use a beat note formed when the bias box is shut off:

 1) Measure an power or voltage at the LNA output and do math based on some
 assumptions.
 2) Capture the full beat note and look at the actual slope as it crosses
 zero.

 You pretty much have to do number 2 before you can use number 1. The LNA
 needs to have low enough gain in this case to not distort passing the full
 signal. The math for 2 is pretty simple. Each cycle is 2*PI radians. Phase
 modulation is normalized to one radian (yes it’s phase … ). You get a
 radians per volt number and move on.

 Wish I knew what Comcast was doing this morning ….

 Bob


  On Dec 22, 2014, at 4:26 AM, Loïc loic.mor...@eai.fr wrote:
 
 
 
 
  Bruce Griffiths bruce.griffiths@... writes:
 
 
  Are you sure that the setup is aligned to minimise AM response?
 
  Are you using 

Re: [time-nuts] Simple AC mains zero-cross detector

[Didier Juges]

Charles,

A commend regarding your ZCD. You propose to use a dual 120V primary
transformer to generate the isolated 120V AC needed by your circuit.
Unless specifically designed for that purpose, the isolation between the
two 120V primaries of a common transformer is probably not as good as the
isolation between primary and secondary, which could be a safety hazard.
Since small transformers with a 120V primary and a true 120V secondary are
hard to find, a better way would be to use two regular step-down
transformers back to back, like two door bell transformers: 120-24-120. You
would then get double isolation.

Didier KO4BB


On Sun, Dec 21, 2014 at 2:52 AM, Charles Steinmetz csteinm...@yandex.com
wrote:

 Mike wrote:

  From a Time-Nut perspective, isn't phase/frequency of the (nominal) 60 Hz
 all we'd be interested in?  Phase is best measured at a zero crossing as
 this is the (only) phase measurement point which is independent of
 amplitude.


 That is the primary interest (as I understand it -- I am not, myself, a
 grid-nut), and the reason the simple ZCD circuit uses this approach.  But
 grid-nuts are also interested in perturbations of the grid voltage caused
 by grid sections going offline and coming back, lightning strikes, etc.,
 etc.  (After all, simply monitoring the ebb and flow of the line frequency
 is about as interesting as watching the tide come in and go out, so they
 naturally want some occasional excitement.)  These anomalies can be
 detected by their effect on the zero crossings of the mains voltage, so one
 data collection serves both purposes at the time-nuts level.

 While the ZCD approach is ideal for monitoring the grid phase/frequency,
 and as a bonus provides timing information about grid anomalies, it does
 not capture all of the information about anomalies.  If you are a utility
 concerned about grid security or making sure that new energy sources play
 nicely with the grid, you probably want more information about anomalies
 than time-stamped zero crossings provide.  Magnus described a system used
 by utilities to track grid anomalies in greater detail.  My reply agreed
 that zero cross detection is not the tool of choice for utilities with such
 concerns, and noted the different needs of grid-nuts and utilities.

 Grid-nuts are well established, and the vast majority of them use
 time-stamped zero crossings as their data sets.  I was concerned that many
 grid-nuts seem to use non-isolated feeds from the mains that, while safe
 enough under normal conditions, are not preferred practice.  I also
 thought that the timing relationship between the ZCD and the actual zero
 cross could be improved and stabilized with a new ZCD.  So, I designed the
 simple ZCD circuit to provide an isolated source of very predictably
 timed pulses with fast edges.  I tested it and it proved to be reliable and
 to have very stable timing with respect to the line zero crossings, so I
 published it and announced it on-list with the first message in this thread.

 Since then, the thread has taken on a life of its own and ranged very far
 from the initial, simple proposition of improved zero cross detection.
 There has been a flurry of comments mostly aimed not at whether the simple
 ZCD is a good AC mains zero cross detector, but more toward whether zero
 crossings are what grid-nuts should be interested in in the first place.
 Since I am not, myself, a grid-nut, I cannot really speak to what grid-nuts
 should be interested in.  I do think that time-stamped zero crossings
 have many significant advantages when one is interested in comparing notes
 with others, and it is comparatively easy data to collect with good
 accuracy -- so, IMO, the choice of grid-nuts to settle on time-stamped zero
 crossings was eminently rational.  The simple ZCD has proven to be an
 excellent front end for such a data collection, and is a project within the
 skills of anyone who knows which end of a soldering iron to grip.  I am
 happy to answer any questions that potential builders may have.

 Personally, I think the thread has more than run its course and should be
 laid to rest.  But if it is to continue, please accept as a given that
 grid-nuts decided long ago that time-stamped zero crossings are the
 appropriate data to collect, and focus on the narrow topic of the simple
 ZCD as a means for accurately detecting zero crossings of the AC mains.


 Best regards,

 Charles


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Re: [time-nuts] Documents relevant to SR620

[Didier Juges]

Apologies to Jean Louis, I obviously missed that part... :)

On Wed, Dec 10, 2014 at 3:47 PM, Jean-Louis Oneto jl.on...@free.fr wrote:

 I just uploaded the file to K04BB. com.
 Best regards,
 Jean-Louis


 On 10/12/2014 19:10, Charles Steinmetz wrote:

 Jeaen-Luis wrote:

  The size of the file is around 5.5 MB.
 Let me know if you are interested, and how I can send it to you.


 You can post it to k04bb.com:

 http://168.144.151.127/manuals/69.143.130.128/1_Upload_Instructions.php

 Best regards,

 Charles



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 --
 Jean-Louis Oneto
 email: jl.on...@free.fr


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[time-nuts] Manual repository

[Didier Juges]

Users of my web site may have had difficulties getting some of the files in
the last couple of months. Particularly, those files that were recently
uploaded.
Typical symptom would be a file that was uploaded, was removed from the
Recent Upload folder (indicating that I moved the file to it's normal
folder) but the file would not show up in search, while being in the normal
folder.
This problem has now been fixed.
Let me know if you come across any new issue.

Thank you

Didier KO4BB

www.ko4bb.com/manuals
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Re: [time-nuts] Linear voltage regulator hints...

[Didier Juges]

Voltage References are usually not able to deliver much more than a few 10mA. 

Having a stable reference means no big temperature gradient on the die, so that 
precludes a big pass transistor.

Most likely, you will have to roll your own.

Using TL431 types of shunt regulator with a single bipolar transistor yields a 
simple and high performing regulator (at least much higher than most 3 terminal 
series regulators) particularly if you use the Linear Tech equivalent part 
(forgot the part number at the moment, but look for shunt regulators)

Didier KO4BB


On December 8, 2014 4:59:24 PM CST, Bob Camp kb...@n1k.org wrote:
Hi

As with anything else it’s a matter of “what’s in your wallet”. 

The parts you are after are called voltage references rather than
voltage regulators. You can get them well down into the low ppm’s / C
or lower. The cutoff is more a function of “do you want to spend $100
or not” rather than a specific level you simply can’t get to. 

Bob

 On Dec 8, 2014, at 1:18 PM, Dan Kemppainen d...@irtelemetrics.com
wrote:
 
 Hi,
 
 In playing with some oscillators and a GPSDO here, I think I'm seeing
a voltage sensitivity issue.
 
 So, I started looking at the output voltage of various regulators vs.
temp. Using standard LM/UA type linear regulators and some LDO's, they
all appear to be pretty sensitive to temperature. (millivolt / few
degrees Fahrenheit sort of sensitivity). Most of the datasheets seem to
ignore temp sensitivity. Almost like they are so bad they don't want to
publish it...
 
 Does anyone have hints on TO-220 or D-Pak type regulators that have
really good temp coefficients and good line regulation? A few PPM/Deg C
might be nice, if possible. Or am I into a 'roll you own' type
design...
 
 Dan
 
 
 
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Re: [time-nuts] Linear voltage regulator hints...

[Didier Juges]

That seems to be generally true, but as always there are outliers.

The LT1034 bandgap reference has 6uVp-p of low frequency noise at 2.5V,
which compares favorably with the 20uVp-p of noise at 6.95V of the LM399.
Of course, for many applications, you will have to amplify the 2V reference
to what you need, which will bring up additional noise while the 6.95V of
the LM399 may be closer to what you need.

Of course, the tempco of the LT1034 does not even get close to that of the
LM399, but it is not thermostatically regulated and draws considerably
lower power. You can't have everything :)

I observe that the LT1034 has two outputs, the high quality 2.5V and a
lower quality 7V.

http://www.linear.com/parametric/Shunt_Voltage_References

Didier KO4BB


On Tue, Dec 9, 2014 at 5:51 PM, Richard (Rick) Karlquist 
rich...@karlquist.com wrote:

 On 12/9/2014 1:30 PM, ed breya wrote:

  buried zener for lowest noise - this eliminates all the low voltage
 references and three-terminal etc regulators that use band-gap
 references. The down side is that the good kind of reference ICs will
 need a higher (like 10V and up) operating voltage than may be available,
 so that complicates it.


 Great post, Ed.  I might add that my understanding of band gap
 regulators is that they rely on amplifying a small DC difference
 in voltage between two transistors.  This also amplifies the SUM
 of the noise of the respective inputs, which jacks up the noise to
 much more than a good zener.  Because of physics, no band gap
 reference will ever be low noise.

 Rick Karlquist N6RK

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Re: [time-nuts] PRS-45 Cs Standard

[Didier Juges]

Magnus and all,

Thanks for the heads up, the Upload Instruction link has been fixed.

The short of it:
click on the Upload File button, use manuals for both login and
password, enter your email and any message for me (optional), select your
file, fill the info the fields about the document as suggested and click
Upload.

Didier KO4BB


On Sat, Dec 6, 2014 at 5:44 AM, Magnus Danielson mag...@rubidium.dyndns.org
 wrote:

 Charles,

 On 12/06/2014 02:30 AM, Charles Steinmetz wrote:


  Do open up and take a look. Do take photos. Do share. :)
 Bet the bottom plate is a good start.

 Cheers,
 Magnus


 Perhaps you can also post the manual to Didier's site (ko4bb.com) so we
 can all follow along?


 1) It's the standard FTS4065 manual.
 2) It was quicker to email it than locate the link.
 3) The upload instruction is unreadable, so I can't upload to Didier's
 site.

 Cheers,
 Magnus

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Re: [time-nuts] PRS-45 Cs Standard

[Didier Juges]

Thanks Magnus, and apologies to all for the not-so-smooth conversion to
the new site. I still have a few random bugs that I am trying to squash and
I appreciate your patience...

On the other hand, performance of the new server seems to be good.

Didier KO4BB

On Sat, Dec 6, 2014 at 7:22 AM, Magnus Danielson mag...@rubidium.dyndns.org
 wrote:

 FTS4065C revision J manual uploaded.

 I knew the login and password where some fake values, but I just could
 not locate it and didnt' have them cached.

 Cheers,
 Magnus


 On 12/06/2014 01:56 PM, Didier Juges wrote:

 Magnus and all,

 Thanks for the heads up, the Upload Instruction link has been fixed.

 The short of it:
 click on the Upload File button, use manuals for both login and
 password, enter your email and any message for me (optional), select your
 file, fill the info the fields about the document as suggested and click
 Upload.

 Didier KO4BB


 On Sat, Dec 6, 2014 at 5:44 AM, Magnus Danielson 
 mag...@rubidium.dyndns.org

 wrote:


  Charles,

 On 12/06/2014 02:30 AM, Charles Steinmetz wrote:


   Do open up and take a look. Do take photos. Do share. :)

 Bet the bottom plate is a good start.

 Cheers,
 Magnus


 Perhaps you can also post the manual to Didier's site (ko4bb.com) so we
 can all follow along?


 1) It's the standard FTS4065 manual.
 2) It was quicker to email it than locate the link.
 3) The upload instruction is unreadable, so I can't upload to Didier's
 site.

 Cheers,
 Magnus

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[time-nuts] NMEA Parser

[Didier Juges]

The Visual Basic NMEA Parser (with source code) has been posted:
http://www.ko4bb.com/NMEAParser

It is work in progress, is not and never was intended as a finished
product. I used it to further my understanding of the NMEA protocol as it
is used by GPS receivers, and to troubleshoot a few other NMEA/GPS related
projects I have in the pile.
It has been mostly tested with a few Trimble ACE-III receivers I have here.

The basic NMEA parsing routines were originally downloaded from
PlanetSourceCode but have been significantly tweaked.

The program has a Trimble TSIP mode, which eventually evolved into the
Thunderbolt Simulator project, so if you want to play with TSIP packets,
the Thunderbolt Simulator is a much better tool (some of it actually
works...) even though I have not uploaded the source code for the
Thunderbolt Simulator yet, so at least here you have some source code to
play with.

The TSIP mode in this tool is even less finished than the NMEA mode. You
have been warned...

One interesting feature (shared with the Thunderbolt Simulator) is the
capability to save and play back log files. The download includes a number
of log files that I downloaded from the Internet or created myself.

I welcome any constructive comment(s) via direct email. If you make useful
addition or bug fix, I would like to get your updates so that everyone can
benefit.

Happy Thanksgiving to all.

Didier KO4BB
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Re: [time-nuts] NMEA Parser

[Didier Juges]

I omitted to specify the source code is in Visual Basic 6.0 Pro. It will
not run under Visual Basic .NET or Visual Studio based on .NET.
The code may be imported, but some rewrite will be required, at least
around the serial comm routines, and probably other.
Otherwise, the project does not use any exotic ocx or dll, just the
standard stuff that is installed with VB 6.0.

Didier KO4BB


On Thu, Nov 27, 2014 at 9:56 AM, Didier Juges shali...@gmail.com wrote:

 The Visual Basic NMEA Parser (with source code) has been posted:
 http://www.ko4bb.com/NMEAParser

 It is work in progress, is not and never was intended as a finished
 product. I used it to further my understanding of the NMEA protocol as it
 is used by GPS receivers, and to troubleshoot a few other NMEA/GPS related
 projects I have in the pile.
 It has been mostly tested with a few Trimble ACE-III receivers I have here.

 The basic NMEA parsing routines were originally downloaded from
 PlanetSourceCode but have been significantly tweaked.

 The program has a Trimble TSIP mode, which eventually evolved into the
 Thunderbolt Simulator project, so if you want to play with TSIP packets,
 the Thunderbolt Simulator is a much better tool (some of it actually
 works...) even though I have not uploaded the source code for the
 Thunderbolt Simulator yet, so at least here you have some source code to
 play with.

 The TSIP mode in this tool is even less finished than the NMEA mode. You
 have been warned...

 One interesting feature (shared with the Thunderbolt Simulator) is the
 capability to save and play back log files. The download includes a number
 of log files that I downloaded from the Internet or created myself.

 I welcome any constructive comment(s) via direct email. If you make useful
 addition or bug fix, I would like to get your updates so that everyone can
 benefit.

 Happy Thanksgiving to all.

 Didier KO4BB


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Re: [time-nuts] Minicircuits 10% discount in December

[Didier Juges]

Another reason is reproducibility. If you or someone else wants to reproduce 
your design, using a well defined and available commercial part makes it much 
easier to achieve the same performance, particularly for RF components.

Didier KO4BB


On November 27, 2014 12:41:34 PM CST, Richard (Rick) Karlquist 
rich...@karlquist.com wrote:


On 11/27/2014 7:07 AM, Tim Shoppa wrote:
 For a hobbyist doing things a few at a time, what advantage is there
to
 buying RF transformers made by Mini-circuits etc., vs winding them
using
 commonly available ferrite cores/binocular cores?

 If I needed to do a production run of 1000+ boards with tiny SMT
 transformers, sure, no problem buying them from mini-circuits or a
 distributor etc. But for hobbyist stuff seems far more flexible to
wind
 them onesy-twosy using not so tiny cores and windings selected for
the
 particular application.

 Tim N3QE

You need the tiny cores to get the performance of the MiniCircuits
transformers.  You just can't get the same bandwidth using macro sized
binocular cores.  Now, if you don't need a lot of bandwidth, then
what you are saying could make sense.  Another issue is stray 
capacitance.  Considerably lower with a tiny core.

I have spent many hours characterizing MiniCircuits transformers
beyond the data sheet specs, and dissecting them to learn how they
do it.  They really do have a lot of rocket science in them.  In
terms of the engineering I am buying (especially in a one-off 
application) they are ridiculously cheap.  And I say that as a fairly 
knowledgeable transformer designer in my own right.

I do keep binocular cores around for higher power transformers, and
for emergencies when I need a transformer yesterday.

Rick Karlquist N6RK
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Re: [time-nuts] Upgrade an HP 5342A microwave frequency counter to have an oven oscillator.

[Didier Juges]

Just remove the TCXO the 10811 just plugs in

Note that there are many different versions of the 10811. I am familiar
with at least two incompatible mechanical configurations: one is
connectorized and the other is not.

Didier KO4BB

On Thu, Nov 27, 2014 at 5:43 PM, Scott McGrath scmcgr...@gmail.com wrote:

 Just remove the TCXO the 10811 just plugs in,  you will need to add the
 heater oven indicator wiring and LED indicator which is usually over the
 power switch   The power supply includes the oven supply already

 Content by Scott
 Typos by Siri

  On Nov 27, 2014, at 5:38 PM, Dr. David Kirkby (Kirkby Microwave Ltd) 
 drkir...@kirkbymicrowave.co.uk wrote:
 
  The HP 5342A has an optional oven oscillator. I just bought one of
  those counters, but mine has a TCXO and is about 50 kHz off at 10 GHz.
  I'm sure I can trim it closer than that, but if possible I'd like to
  stick an oven oscillator in it. Does anyone know what is involved? I
  have at least one 10811A oscillator here that I could stick inside,
  but does it need any more, or just the oscillator?
 
  Someone said the oscillator should be an 10544-60011, but a 10811A is
  backwards compatible.
 
  Dave
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Re: [time-nuts] LTE-Lite Plans

[Didier Juges]

Said,

Your drawing looks better than those by Bob Pease, and he was never
embarrassed by his :)
Thank you for your extensive contributions to time nuts

Didier KO4BB


On Tue, Nov 25, 2014 at 7:28 PM, S. Jackson via time-nuts 
time-nuts@febo.com wrote:

 Guys,

 I never expected such an intense discussion about using and buffering  the
 outputs from the LTE-Lite board since the actual circuit to use can  be
 quite simple.

 To address these questions, I drew up a simple schematic that uses a DIP-14
  74AC04 gate, six resistors, and two caps. Everyone who can solder should
 be able  to build this simple circuit as a dead-bug type build on a
 copper-clad  board.

 This circuit will buffer all three outputs (1PPS, TCXO RF, and Synthesixed
 RF) of the LTE-Lite eval board with CMOS 3.0V levels that can drive 50 Ohms
  terminations. For simplicity I grab the 3.0V power from the DIP-14 TCXO on
 pin  14 of that part on the eval board, even though I would strongly
 suggest to use a  separate low noise 3.3V or 5V power supply to power the
 74AC04
 chip.

 You can add 100nF caps in series to the two RF signals before they feed
 into the coax output connectors for less power consumption and removing DC
 for
  instruments that don't like DC inputs.

 Using a single IC for the three signals will result in crosstalk between
 the signals, but it should be clear from the schematics how one could break
 up the signals by using three independent ICs to minimize crosstalk.

 We use this circuit in a small box here using SMT components, and it works
 really well.

 Excuse my horrible writing, using keyboards has made my fingers  numb..

 Hope that helps,
 Said

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Re: [time-nuts] LTE-Lite Plans

[Didier Juges]

Jim,

I have somewhere a piece of VB 6.0 code that decodes NMEA sentences and puts it 
pretty on the screen (at least that's how I remember it :). I am not at home at 
the moment but I'll be glad to send it to you if you are interested. May not do 
what you want, but it will get you started.

Didier KO4BB
www.ko4bb.com

On November 25, 2014 1:42:42 PM CST, Jim Miller j...@jtmiller.com wrote:
I have one of the LTE-Lite 20Mhz units and plan to use it as a
frequency
reference for my ham radio gear. My planned setup is as follows:

I'm putting it in the recommended Hammond enclosure powered by a USB
cable
from my PC. I had originally planned to use the wall wart provided but
I
want to get status from the unit without hacking a window in the top to
see
the LEDs so I plan to use TBD software to provide a status check. I
briefly
thought about doing something with an Arduino and display shields but
that
seemed like too much work for now.

I'm using a inverting D FF from TI (SN74aup1g80) as a divide by 2 to
provide 10Mhz. The chip and associated passives will be on a little
circuit
board mounted in the open area normally reserved for the external
oscillator. The output of the chip will be connected via a series
resistor
of about 400 ohms to a SMA connector. This resistor will limit the load
on
the FF and the LTE-Lite power source. Power will be taken from C6.

This output will only go a few inches to a DEMI 10Mhz 4 way splitter
The
input of the splitter will be equipped with an additional ERA-2+
amplifier
(50 ohm input) which will restore the signal levels lost due to the
series
resistor in the LTE-Lite addon. The DEMI splitter will also be equipped
with a manual power switch which will allow me to kill the output of
the
box if the GPSDO fails for some reason.

The little hockey puck antenna will be mounted directly outside the
shack
wall near a south facing wall which will limit the visibility to only
half
the horizon. I'm assuming this will be enough for my modest needs.

The four outputs will be used as follows:

One will go to the K3 ExtREF to provide an external reference.

Two will go to separate TX/RX converters for low frequency (600Khz)
use
and be used with the transverter I/O on the K3.

The last will be used as a general calibration reference.

When the power switch on the DEMI splitter is turned off the K3 will
revert
to using its internal TXCO.

I leave the PC running 24/7 and the power to the LTE-Lite would only be
interrupted when the PC is rebooted. I don't need a frequency reference
during the reboot time since I always operate my rig with the PC on and
running. The TBD status software will tell me when the LTE-Lite is
synched
up again. The PC is served by a UPS and the shack circuit is one which
is
served by our whole house generator.

I have the DEMI splitter built up and working. Now just waiting on
enclosure from Digikey. I should have everything running by mid
December.

I still need to figure out what to use for the status software. Ideally
I'd
like an applet to display appropriate status indications on my monitor
for
now I'll examine the uBlox and Putty and if not satisfactory perhaps
I'll
write something in VB.

Feedback and suggestions welcome.

73

Jim ab3cv
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Re: [time-nuts] rs-422 rs-232 to fast ethernet converter

[Didier Juges]

Graham,

There are a number of WiFi to serial modules like the one I use on my 
Thunderbolt monitor: The Microchip WiFly RN-XV-171. Once configured (typically 
using a PC), they will present a TCPIP port (TCP or UDP) from which you can get 
and send data directly to the serial port.

Alternately, you can use Digi XBee modules that work like wireless RS232 
isolators. I use the XSC Pro 900 MHz for a number of projects, including data 
loggers that are out of WiFi range. You can get well over a mile in open space 
with those. They are limited to 19200 bauds at the most.

Didier KO4BB

On November 22, 2014 4:47:15 PM CST, Graham planoph...@aei.ca wrote:
I have been contemplating how I will would like to interface to the 
KS-23461 devices using rs-422.

One option is a rs-422 to USB cable. Seems easy enough.

But another option I keep stumbling across is a rs-422/rs-232 to fast 
ethernet such as:

http://www.transition.com/TransitionNetworks/Products2/Family.aspx?Name=SDSFE3110-120

Frankly, I have no first hand knowledge or experience with these 
devices. First glance suggests that it might just be what I want - easy

access to the KS-23461 ports through a connection to my local network 
without having a PC of some sort close by.

So, any first hand experience with such devices? Good idea or bad?

cheers, Graham ve3gtc

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Re: [time-nuts] Lucent KS-24361 Web Page

[Didier Juges]

Brooke,

Following the links from your page (nice work, thank you) lead me to your 
Thunderbolt page where you ponder the death of your iCruze monitor.

If you refer to the picture of the microprocessor board, you will notice that 
the locations marked D1, D2 and D3 are populated by zero ohm resistors. That 
means that the 3 V microcontroller was powered from 5V. I am actually amazed 
that they worked at all, let alone worked for a while.

It is a shame that fluke.l saved on the cost of 3 diodes that way. The 1N4148 
is $.02 at Mouser in 25 pieces lots. 

Didier KO4BB


On November 18, 2014 8:48:33 PM CST, Kris Keener w...@outlook.com wrote:
Nice write up, all of us on bench W enjoyed it. :-)

73,

Kris, WT5V

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Brooke
Clarke
Sent: Tuesday, November 18, 2014 4:42 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] Lucent KS-24361 Web Page

Hi:

I've received the components of the Z3810A system and have some 8x10
color glossy photographs with circles and arrows and a paragraph on the
back of each one explainin' what each one is for.  But need to find the
connectors to make up the DC power cables.

http://www.prc68.com/I/KS-24361.html

Mail_Attachment --
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
http://www.prc68.com/I/DietNutrition.html
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Re: [time-nuts] 10MHz Rubidium reference source for frequencycounter

[Didier Juges]

Charles,

You can always upload time-related material to my Manuals page:

www.ko4bb.com/manuals

Didier KO4BB

On November 3, 2014 2:43:47 PM CST, Charles Steinmetz csteinm...@yandex.com 
wrote:
Tom wrote:

As I understand it, his project is to use the high frequency output 
of a ublox NEO-7M to discipline a MV89 with a James Miller-style
analog PLL.
*   *   *
(perhaps someone can post an English translation for us)

Tom,

I have a machine-translated PDF (~2.5MB), but nowhere to put it 
up.  If you have web space for it, please feel free to do so 
(assuming that Karen does not object).

I have reservations about the potential of any Miller-style GPSDO, 
because using an analog PLL essentially guarantees that the crossover 
to GPS will be at a tau orders of magnitude lower than it should be 
-- the Miller unit crosses over about 3 OOM too low (see attached 
plot, from http://www.leapsecond.com/pages/gpsdo/).

The beloved Thunderbolt also crosses over about 2.5 OOM too early, if 
you use the factory loop settings (id.).  But it has an ADPLL with 
adjustable parameters, so a time nut can tune the loop for best 
performance with the particular OCXO in the unit.  (See 
http://www.ke5fx.com/tbolt.htm.)

Best regards,

Charles






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Re: [time-nuts] Phase, One edge or two? (was Digital mixing with a D Flip Flop)

[Didier Juges]

Even more effective would be to sample the entire 10MHz waveform instead of 
just the zero crossing. By doing a best fit of the entire waveform, you should 
be able to estimate the zero crossing with much greater precision because now 
the noise is averaged over the entire waveform instead of a single point at the 
zero crossing.

I wish my signal processing were better than they are and that I had some time 
to evaluate that.

Didier KO4BB


On October 22, 2014 1:09:11 PM CDT, WarrenS via time-nuts time-nuts@febo.com 
wrote:


The recent  discussions about the simple digital mixer got me thinking
about
the performance vs. complexity trade offs when measuring accurate, high
resolution, phase drift differences between two oscillators.
It would seem to me, that using both the positive and negative slope
edges
of the high freq sinewave signal is a better way to go.
Is using just one edge, acceptable for a 'state of the art' Phase drift
measurements?

I am not suggesting  the KISS approach is the wrong solution for Simon.
I am questioning if the paper posted, is the best way for CERN to make
a
state of the art femtosecond DDMDT?

Here is an extreme example of throwing away useful data for the sake of
simplicity:
When measuring phase drift of a 10 MHz osc using just a 1PPS signal,
19,999,999 other possible data points are being discarded.
Using all possible data points could decrease the noise floor
considerably.
(by ~5,000 to 1)

ws


---
 Tom Posted
 Re: [time-nuts] Digital Mixing with a BeagleBone Black and D Flip
 Hi Simon,

 Some additional info. I first heard about the D-FF method of
frequency 
 comparison in the late 90's (from Rick Hambly, I think) on the old
gps 
 mailing list. It sounded really interesting. Since then, the subject
has 
 turned up every few years on this list. But each time, the topic
seems to 
 go away quietly with little or no data, plots or explanation. In 
 addition, none of the commercial products I've taken apart appear to
use 
 this approach. Hmm. So that begs the question -- what's really going
on, 
 and why.

 I'm enjoying this thread because you've shown both technical
competence 
 and optimistic persistence. Perhaps once and for all, with your
efforts, 
 we can settle this matter. You will either find a working
combination 
 with excellent performance, or you will uncover enough uncontrolled 
 variables that you never want to try it again. Either way, we all
learn a 
 lot. Keep the photos, data, and plots coming.

 Thanks,
 /tvb
 --
 Re: [time-nuts] Digital Mixing with a BeagleBone Black and D Flip
Flop

 Bruce posted 

http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/36903/1/01-2617.pdf

 among other things illustrates a modified approach to the offset 
 generator by replacing the intermediate phase locked VCXO with a
bandpass 
 filter.

 --
 Re: [time-nuts] Digital Mixing with a BeagleBone Black and D Flip
Flop
 Simon posted   www.ee.ucl.ac.uk/lcs/previous/LCS2011/LCS1136.pdf ...
 The idea is based on the following article which describes creating a
 digital DMTD with an FPGA for clocks @ 125mhz:   

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Re: [time-nuts] GPS for ntp

[Didier Juges]

Check lightningmaps.org, mentioned on this list before for lightning location 
via TOA using STMicro Cortex -M4 devices.

Didier KO4BB


On October 20, 2014 8:39:16 PM CDT, Joseph Gray jg...@zianet.com wrote:
What does everyone think of this GPS module for ntp use? According to
the
specsheet, it uses a Ublox Neo-7N.

http://www.ebay.com/itm/RY725AI-10Hz-UART-USB-interface-GPS-Glonass-QZSS-antenna-module-flash-memory-/181562403752

I'm thinking about using it for a Beaglebone ntp server. I know there
was
some discussion about Beaglebones a while back. Has anyone gotten ntpd
with
PPS and time stamping running on a Beaglebone yet (like on the Soekris
Net4501)?

Does anyone want to take a wild guess as to the best/worst case UTC
offset
I might get with such a setup? I realize that I'd have to try it to
really
find out, but guesses and advice from those more knowledgeable is
always
appreciated.

What I'm really after is to eventually have several Beaglebones
scattered
around the area as part of a TDOA DF network. I have spare radios to
dedicate to the task. Each fixed node will timestamp incoming
transmissions
and then relay that information to a central location. The central
system
will use the data to calculate the location of the transmitter.

Does anyone here have any experience with this sort of thing? Would you
recommend a better way of accurately timing the transmissions vs using
ntp
on each Beaglebone?

I know that TDOA is used by the cellular companies. Is anyone aware of
some
user level projects or source code for this? I've Googled a bit, but
haven't turned up much. There was one thesis about an Amateur doing
part of
this, but he didn't have much detail on the satellite nodes and didn't
describe anything about the centralized processing part.

I have one Beaglebone White that I got cheap, so I have something to
get
started with. Later, as I figure out things, I'll buy a few Beaglebone
Blacks.

Joe Gray
W5JG
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Re: [time-nuts] FE-5680 Linux command line tool

[Didier Juges]

I use that chip in an old project with an 8051 microcontroller. They are 
becoming obsolete, I had to switch to the PSD913F if I recall correctly (or 
maybe the other way around?)

I have a couple of the programmers too. They work from the printer port, you 
are talking about certifiable dinosaurs :)

Didier KO4BB


On October 11, 2014 3:19:52 PM CDT, Tom Wimmenhove tom.wimmenh...@gmail.com 
wrote:
It's a chip (PSD813F) which has 1MBit flash, 16Kbit SRAM and 256Kbit
EEPROM. It's old school with parallel data/address bus and all that :)
It
does have JTAG.

Regards,
 Tom

On Sat, Oct 11, 2014 at 7:45 AM, Didier Juges shali...@gmail.com
wrote:

 Most EEPROMs have I2C or SPI interfaces. Some Flash chips have JTAG.

 Didier KO4BB

 On October 10, 2014 4:47:19 PM CDT, Tom Wimmenhove 
 tom.wimmenh...@gmail.com wrote:
 Thanks Joe!
 
 I don't have the clip-ons but of course I could get them. I know the
 chip
 has a JTAG interface, but I've only used JTAG with chips that came
with
 a
 programmer and software :) (except with OpenOCD over parport once,
but
 that
 was in the stone age).
 
 Another question about the EEPROM dump Elio Corbolante. The chip has
a
 256Kbit (32KB) EEPROM and the dump is 160K:
 -rw-rw-r-- 1 tom tom 160K nov  8  2012 FE5680A_EEPROM.bin
 
 Which part in this dump is the actual data from the EEPROM?
 
 Thanks in advance.
 
 Regards,
  Tom
 
 
 
 On Fri, Oct 10, 2014 at 12:21 PM, Joseph Gray jg...@zianet.com
wrote:
 
  I don't know how crowded the board is, but I would use an SMD DIP
 clip
  instead of unsoldering the chip.
 
  Joe Gray
  W5JG
   On Oct 10, 2014 8:30 AM, Tom Wimmenhove
tom.wimmenh...@gmail.com
  wrote:
 
   I recently came across a thread on this list about undocumented
 FE5680
   commands. I have been using a little linux command line tool I
 wrote
  years
   ago for tuning the unit and decided to add these commands to it.
   Since this mailing list was the place I found the unit (someone
 linked to
   an ebay seller) I figured I' d join the list and throw it on
here
 :)
   http://www.tomwimmenhove.com/otherstuff/fe5680-0.2.tgz
  
   Now, the bad news. I had my unit running overnight while logging
 the
  serial
   command output that reads the ADC, and in the morning it was no
 longer
   locked. The 10MHz signal disappears about 5 seconds after
power-on,
 and
   programmed offset was somehow reset to zero (it had been set to
 -645). So
   it appears as if the internal EEPROM has been corrupted.
   I read a post from Elio Corbolante where he posted EEPROM and
 firmware
   dumps. Anyone have any idea on how to re-write this firmware
back
 into
  the
   EEPROM by hand (would this be possible through JTAG, or do I
 actually
  have
   to solder the chip out of there? :) ) Or maybe there's someone
 willing to
   sell their broken unit I could take the chip out of?
  
   Regards,
   Tom
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Re: [time-nuts] FE-5680 Linux command line tool

[Didier Juges]

Most EEPROMs have I2C or SPI interfaces. Some Flash chips have JTAG.

Didier KO4BB

On October 10, 2014 4:47:19 PM CDT, Tom Wimmenhove tom.wimmenh...@gmail.com 
wrote:
Thanks Joe!

I don't have the clip-ons but of course I could get them. I know the
chip
has a JTAG interface, but I've only used JTAG with chips that came with
a
programmer and software :) (except with OpenOCD over parport once, but
that
was in the stone age).

Another question about the EEPROM dump Elio Corbolante. The chip has a
256Kbit (32KB) EEPROM and the dump is 160K:
-rw-rw-r-- 1 tom tom 160K nov  8  2012 FE5680A_EEPROM.bin

Which part in this dump is the actual data from the EEPROM?

Thanks in advance.

Regards,
 Tom



On Fri, Oct 10, 2014 at 12:21 PM, Joseph Gray jg...@zianet.com wrote:

 I don't know how crowded the board is, but I would use an SMD DIP
clip
 instead of unsoldering the chip.

 Joe Gray
 W5JG
  On Oct 10, 2014 8:30 AM, Tom Wimmenhove tom.wimmenh...@gmail.com
 wrote:

  I recently came across a thread on this list about undocumented
FE5680
  commands. I have been using a little linux command line tool I
wrote
 years
  ago for tuning the unit and decided to add these commands to it.
  Since this mailing list was the place I found the unit (someone
linked to
  an ebay seller) I figured I' d join the list and throw it on here
:)
  http://www.tomwimmenhove.com/otherstuff/fe5680-0.2.tgz
 
  Now, the bad news. I had my unit running overnight while logging
the
 serial
  command output that reads the ADC, and in the morning it was no
longer
  locked. The 10MHz signal disappears about 5 seconds after power-on,
and
  programmed offset was somehow reset to zero (it had been set to
-645). So
  it appears as if the internal EEPROM has been corrupted.
  I read a post from Elio Corbolante where he posted EEPROM and
firmware
  dumps. Anyone have any idea on how to re-write this firmware back
into
 the
  EEPROM by hand (would this be possible through JTAG, or do I
actually
 have
  to solder the chip out of there? :) ) Or maybe there's someone
willing to
  sell their broken unit I could take the chip out of?
 
  Regards,
  Tom
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Re: [time-nuts] Sun Outage

[Didier Juges]

Just to put that in perspective, we're measuring a few degrees of phase 
shift in a 32 GHz signal on a path that is over a billion km long.

Now this is fully qualified nuttiness :)

Didier KO4BB


On October 10, 2014 8:17:13 AM CDT, Jim Lux jim...@earthlink.net wrote:
On 10/9/14, 10:16 PM, Andy wrote:
 Bob Stewart b...@evoria.net wrote:


 It occurred to me that one could use satellite signals as a
meteorological
 instrument to measure the water density in the atmosphere above you. 
I
 wonder if the NWS does that.


WHy yes they do: that's what weather radar is. It detects the 
reflections from the rain drops or ice crystals in the storms. These 
days, it's doppler radar, so not only do you get the density of the 
return but whether it is moving towards or away from the radar.  If 
multiple radars in different places cover the same volume, you can get 
full X-Y motion.


On a more time-nutty note, they also use the small variations in GPS 
signal propagation to do this kind of measurement.  COSMIC (and soon to

be launched COSMIC-2) measure GPS signals passing through the
atmosphere 
from satellite to satellite- grazing the earth's surface, and by 
measuring the phase and amplitude variations (because you know the 
underlying GPS signal is locked to an atomic standard), you can infer 
the properties of the atmosphere at various elevations.

Such radio occultation measurements are the 3rd or 4th most useful 
measurement in feeding the numerical models that are used for weather 
prediction.


On an even more gnat's eyelash time measurement note:
We use radiometers (basically a sensitive power meter) to measure water

vapor content (and, incidentally, cloud cover) at the DSN stations, to 
remove some of the variation in the measurements of propagation delay
to 
and from spacecraft.  By carefully gnawing away at all sources of
error, 
we can measure the round trip light time with accuracies of 1E-14 (1000

second tau), which is how we can measure range to something at Saturn
to 
a few cm, and radial velocity (range rate) to a few mm/sec.

Just to put that in perspective, we're measuring a few degrees of phase

shift in a 32 GHz signal on a path that is over a billion km long.


http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/18497/1/99-1986.pdf, 
page 7, shows some radiometer data from a 13.402 GHz radiometer I built

installed in Las Cruces, NM.  It was easy to tell when it was overcast 
or clear: clear is cold, because you're seeing sky; overcast is warm, 
because you're seeing the reflection of the ground, and the warm water 
in the clouds.




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