from:"Robert DiRosario"

[time-nuts] Re: HP105B

2022-01-18 Thread Robert DiRosario


What about the HP 5087A Distribution Amplifier?

When did that start and end?  It's gone through all of
the "color" changes over the years.

And then there is the 355 attenuator:
https://www.hpmemoryproject.org/timeline/art_fong/hp355_01.htm
They report it was in the HP catalog from 1958 through the 2006 Agilent 
catalog, 46 years.



On 01/16/2022 04:18 PM, Louis Taber wrote:

Hi All,

The HP 105B is in the HP catalogs for a 33 year period, 1968 through
2000.  That is a 33 year run.  Is this an HP/Agilent/Keysight record?
  Does anyone know how the newer units were fabricated?

It is just barely mentioned in the year 2000 catalog.  The price went up
from $1800 to $9700 in 26 years.  About 5.5 times the original price.  I
wonder what the price was in 2000.

I was looking at the old HP catalogs at http://hparchive.com/hp_catalogs
for the HP105B Quartz Oscillator.  The 1967 catalog has the 106A and
107AR/BR on page 538, but no 105A/B

1968 $1800 p594-597
1969 $1800 p648-651
1970 $1800 p624
1972 $1950 p237
1973 $2145 p284
1974  No catalog or supplement published
1975 $2470 p287
1976 $2725 p276
1977 $2950 p274
1978 $3250 p300
1979 $3500 p282
1980 $3750 p284
1981 Not listed
1982 $5750 p307
1983 No price p281
1984 No price p275
1986 $5800 p257
1987 $6400 p340
1988 $6800 p467
1989 $7500 p487
1990 $8600 p491
1991 $9000 p510
1992 $9500 p556
1993 $9700 p498
1994/5/6 No catalog on the site.
1997 No price p493
1998 No price p503
1999 No price p508
2000 "The HP 105B quartz frequency standard uses the HP 10811D and is
available as a complete standalone instrument."  p 491
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[time-nuts] Raspberry Pi with TimeHat thinks it's 2002!

2021-12-31 Thread Robert DiRosario


My Raspberry Pi with a TimeHat thinks it's May 18 2002.

When I refresh  / reload the web page the time updates fine, but not the 
date.


Fix Data
Fix Type3D Fix
Fix StatusDGPS Fix
Time
UTC2002-05-18T00:47:58.000Z
Leap Seconds18


Dilution of Precision
GDOP 1.63
HDOP 0.94
PDOP 1.44
TDOP 0.76
XDOP 0.58
YDOP 0.74
VDOP 1.09

Error Estimates
epc 0 m/s
eph 2.012 m
eps 0 m/s
ept0.005 s
epx 2.173 m
epy 2.788 m
epv 2.449 m
sep 1899.81 m
ecef pAcc 3.17 m
ecef vAcc 0.32 m


Satellites
Seen 23  Used 15
PRN ElvAzm SNRUsed
GP1163 105 39 Y
GP7743 184 30 Y
GP8819 59 32 Y
GP131314 289 39 Y
GP141456 317 30 Y
GP171743 259 24 Y
GP191919 248 35 Y
GP212145 58 44 Y
GP303061 226 28 Y
SB1334620 244 30 Y
SB1385135 223 34 Y
GL157978 99 39 Y
GL178166 24 42 Y
GL188257 223 40 Y
GL248814 34 29 Y
GP334 135 0 N
GP222215 113 16uN
GP28280 0 35uN
SB1354823 241 36 N
GL147826 136 0 N
GL168036 326 0 N
GL198312 216 20 N
GL279166 24 0 N

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[time-nuts] Re: Query about List and about 10 MHz Distro

2021-08-29 Thread Robert DiRosario

Andrew Sureflex (FSJ) is a lot more flexible then the LDF4 Healix, which
is what you find a

lot of on ebay and at hamfests.

Here is some 1/4" Sureflex, new:

Andrew Type N Male to Type N Male Sureflex Cable 30 feet
F1RNA-PNMNM-30-L1 NEW!

https://www.ebay.com/itm/173863049072
US $30.00 + $13.02 Shipping. For two pieces shipping goes to $16.33,
for three $22.90

You can cut it with a hacksaw, do NOT use wire cutters. Connectors can be
installed with just hand tools.

If you move the test equipment around it's not very practical, but if
it's setup on

a bench or in a rack it will work.

Robert

On 08/29/2021 09:51 AM, Bob kb8tq wrote:

Skin depth is what gets you with most coax at 10 MHz, even with the “double
shield” stuff. Hardline with a nice heavy outer would do better. It’s not
terribly
practical around the typical lab. Might not be a bad choice for a “burry in the
yard”
setup though. With normal cable, the losses from the soil at normal burial
depths make a good shield, that makes dealing with it questionable even there ….

Bob

On Aug 29, 2021, at 9:36 AM, Robert DiRosario wrote:

What about double shielded RG-223, or Thinnet ethernet cable?
Most Thinnet has both a braided shield and a foil wrap.

Robert

On 08/28/2021 08:26 PM, Bob kb8tq wrote:

Anything you do that has a bunch of 10 MHz cables running out from here or there
will impact your ability to listen to WWV at 10 MHz :) Other than killing all
the sources,
there is no silver bullet.

Bob

On Aug 28, 2021, at 7:57 PM, Dana Whitlow wrote:

Bob, my own motivation for going to fiber was entirely different. I
simply wanted to
run 10 MHz all over the place from reference sources in disparate
locations in the
house, and I quickly discovered that cable leakage was embarrassingly
severe. So
I shut down and began contemplating a fiber link. But then reality set in
and I realized
that running fiber across the house had its own big problems, so I set the
project aside.

Dana

On Sat, Aug 28, 2021 at 3:32 PM Bob kb8tq wrote:

With a whole variety of pretty good OCXO’s going for cheap money
on eBay, it’s likely less expensive to do cleanup oscillators on the link
compared to going crazy with low noise optical this or that. Yes, you
will be getting something in the high 150’s for noise, but still pretty
good
for $10.

If you need better, spend $50 or so on a 10811. Still less money than
some of the crazy fiber stuff.

With either one, send over a high enough frequency that the loop isn’t
dealing with reference spurs in any significant way. Given the clock rates
Ethernet runs at these days, that part should be fairly straightforward.

This *assumes* that there is a crossover somewhere practical between
the fiber noise and the noise on the optical gear. You should be able to
work out what it is with some fairly normal phase noise or ADEV testing.

Bob

On Aug 28, 2021, at 3:03 PM, Dana Whitlow wrote:

I was looking for something similar about 18 months or so ago. Although

haven't taken any
action yet, I concluded that one could do a nice job for under $200 per
segment, including the
transmitter and receiver modules and lots of connectorized multimode
fiber. What I *don't* know
is what the phase noise performance would be, except that I do know that
the fiber's VF *is*
materially influenced by temperature.

I was looking primarily at the HFBR-2416 for the fiber receiver, and the
HFBR-1412 (standard
power) or the HFBR-1414 (high power option) for the transmitter Unlike
most of the available
models, these are fundamentally analog devices, meaning that you can
transmit sinewave
10 MHz through them. At the time I was looking, Mouser was selling these
for about $20 each.

See the datasheet at

https://www.mouser.com/datasheet/2/678/AV02-0176EN_2019-02-15-1827546.pdf

with particular attention to page 21 regarding the HFBR-2416 receiver.

I was also looking at Fiber Instrument Sales for patch cords. We bought

lot of fiber stuff from
them at Arecibo, and I was always happy with them. See:

https://www.fiberinstrumentsales.com/catalog-cable-assemblies?gclid=Cj0KCQjwvaeJBhCvARIsABgTDM7eNTkP2nQbyFzhcwDE38VnSEP879MBKV1ZyDq2YrnEtOn7_VfzjbkaAtpfEALw_wcB

Somebody had pointed out yet another source of connectorized fibers

("patch

cords") to me, but I cannot find the name
at the moment.

Dana K8YUM

On Sat, Aug 28, 2021 at 11:52 AM AC0XU (Jim)
wrote:

I am hoping that you can help me about a couple of things:

1) My time-nuts summaries sometimes appear unformatted and unreadable.

All

the text from all the postings is crammed together without spacing. How

can

I fix it?

2) I want to distribute 10 MHz references by fiber. There are
RF-over-Fiber products available, but too expensive for me (thousands of
$$$ per xmit/rcv set). I am thinking that it should be possible to use
fiber Ethernet components to do this. I don't mean IEEE 1588 but a much
simpler,

[time-nuts] Re: Query about List and about 10 MHz Distro

2021-08-29 Thread Robert DiRosario

What about double shielded RG-223, or Thinnet ethernet cable?
Most Thinnet has both a braided shield and a foil wrap.

Robert

On 08/28/2021 08:26 PM, Bob kb8tq wrote:

Anything you do that has a bunch of 10 MHz cables running out from here or there
will impact your ability to listen to WWV at 10 MHz :) Other than killing all
the sources,
there is no silver bullet.

Bob

On Aug 28, 2021, at 7:57 PM, Dana Whitlow wrote:

Dana

On Sat, Aug 28, 2021 at 3:32 PM Bob kb8tq wrote:

If you need better, spend $50 or so on a 10811. Still less money than
some of the crazy fiber stuff.

Bob

On Aug 28, 2021, at 3:03 PM, Dana Whitlow wrote:

I was looking for something similar about 18 months or so ago. Although

See the datasheet at

https://www.mouser.com/datasheet/2/678/AV02-0176EN_2019-02-15-1827546.pdf

with particular attention to page 21 regarding the HFBR-2416 receiver.

I was also looking at Fiber Instrument Sales for patch cords. We bought

lot of fiber stuff from
them at Arecibo, and I was always happy with them. See:

https://www.fiberinstrumentsales.com/catalog-cable-assemblies?gclid=Cj0KCQjwvaeJBhCvARIsABgTDM7eNTkP2nQbyFzhcwDE38VnSEP879MBKV1ZyDq2YrnEtOn7_VfzjbkaAtpfEALw_wcB

Somebody had pointed out yet another source of connectorized fibers

("patch

cords") to me, but I cannot find the name
at the moment.

Dana K8YUM

On Sat, Aug 28, 2021 at 11:52 AM AC0XU (Jim)
wrote:

I am hoping that you can help me about a couple of things:

1) My time-nuts summaries sometimes appear unformatted and unreadable.

All

the text from all the postings is crammed together without spacing. How

can

I fix it?

wave

(coax) to square wave (fiber) to sine wave (coax). I am looking for a

low

cost solution. Any thoughts or recommendations??

Thanks!

Jim
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[time-nuts] 1 PPS question

2021-08-28 Thread Robert DiRosario

For GPS receivers that give 1 PPS output the spacing between pulses is, 
obviously, very accurate.
Are the pulses synchronized to something, like UTC seconds, or does it 
vary from one

manufacturer to another, or even one unit to another?

Thanks
Robert
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[time-nuts] Re: GPS antenna question

2021-08-25 Thread Robert DiRosario


Somehow I missed this message.

>This probably comes under tha category of more than you want to know...
No, it's NOT more than I want to know, it's what I want to know.

>Stanford published a series of lectures on GPS.
>https://www.youtube.com/playlist?list=PLGvhNIiu1ubyEOJga50LJMzVXtbUq6CPo

>I think there is a good book or two with enough info to design 
hardware and write software.

They list two books, both look good, from the preview on Amazon.


Thanks for the link.
Robert


especially for covering the 0-satellite case.

It's more complicated than just figuring out the error in the satellite's
clock.  You also have to consider the error in the satellite orbit, the
difference between where you think it is and where it actually is.



I wish stuff like this could be on a web page or FAQ or something, where it
was easily discoverable.

It's complicated.



This probably comes under tha category of more than you want to know...

Stanford published a series of lectures on GPS.
   https://www.youtube.com/playlist?list=PLGvhNIiu1ubyEOJga50LJMzVXtbUq6CPo

I think there is a good book or two with enough info to design hardware and 
write software.


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[time-nuts] Re: Efratom LPRO-101 Rubidium question....

2021-08-23 Thread Robert DiRosario


Dana,


I make phase comparisons between the 10 MHz outputs of a GPSDO and the Rb
under test using a simple quadrature demodulator, with the I & Q outputs
displayed on a 2-chan DSO.


Can you explain what you do?  Do you just connect the two 10 MHz signals
to the input of the demodulator?

Robert


On 08/22/2021 11:16 AM, Dana Whitlow wrote:

C'mon guys- when you speak of a frequency error in Hz, you should also
specify "at
what frequency" *in the same breath*.  Or better yet, always specify
frequency errors in
relative terms.

Hundreds of Hz at 10 Mhz is unthinkable for a Rb.   Even at 8.2 GHz, 100 Hz
error is about
12E-9, which is likely to be outside the EFC tuning range of some (if not
most) Rb standards.
Both of my Rbs have a tuning range of only roughly 2E-9 via the EFC input.
Outside that
range, much sterner measures must be taken, which I frankly dread.

The two Rbs that I own (an L-Pro and a PRS-10) both tend to drift upwards
in frequency
to the tune of about 1E-11 or 2E-11 per month.  Superimposed on that are
random
variations of around 1E-11 on a time scale of a few hours.

I make phase comparisons between the 10 MHz outputs of a GPSDO and the Rb
under
test using a simple quadrature demodulator, with the I & Q outputs
displayed on a 2-chan
DSO.  I use the "roll mode" display feature on the DSO at its slowest speed
(1000 sec/div)
and just leave things running continuously for up to several days.  On my
DSO a full screen
width is 14000 sec (slightly under 4 hours), and I just take a glance from
time to time as I
happen to pass by.

Someone suggested a 100 sec measurement with a counter, but that is right
in the realm
where GPSDOs are typically the most noisy, so a single measurement is
likely to have
rather large errors.  One would have to record a fairly large number of
such measurements
(several hundreds of them) and plot them out to get a good assessment of
what the Rb is
actually doing.  WIth the IQ phase difference display, one can get a pretty
decent estimate of
the needed tuning correction, without doing any real work at all, in a day
or so.

When I'm doing something requiring the best frequency accuracy, I keep the
'scope display
running while I'm doing the serious work, and note the frequency error of
the Rb at the time
for use in correcting the final result.  BTW, I don't see much "settling"
effect after making
tuning changes- the correction made seems to take effect essentially
immediately (as best
as one can tell in the presence of GPS noise).  By comparing two Rbs, I can
investigate
settling effects quite well without the noise having anything to do with it.

Dana


On Sun, Aug 22, 2021 at 8:41 AM Matthias Welwarsky 
wrote:


Hi,

a Rb will not be long-term accurate. I'd trust a GPSDO to be long-term
accurate. A hundreds-of-Hz offset between the LPRO and the GPSDO certainly
points into the direction of the LPRO being off the mark.

When you adjust the LPRO, be sure to give it ample time to stabilize.

BR,
Matthias

On Samstag, 21. August 2021 14:50:24 CEST mp...@clanbaker.org wrote:

Hello Time-Nutters--

I am working on building a downlinking AZ/EL tracking dish set up to
receive the 8.2 GHz telemetry from the Suomi JPSS polar orbit
meteorological/environmental satellite.  The receiver seems to be
working OK but it periodically appears to slowly drift frequency by
300 Hz to 400 Hz.  I need some way to accurately determine what
the actual RX receive frequency is.

I have a vintage Efratom LPRO-101 Rubidium 10 MHz oscillator.
I originally got it thinking that it would provide a decent
phase-lock reference for my freq-counters, o-scopes, spectrum
analyzers and Agilent/HP vector network analyzer.

The only other item I have that has (or should have) a reasonably
accurate 10 MHz reference output is a Trimble Thunderbolt.
However, there is a several hundred Hz freq difference between the
Efratom and the Trimble T-bolt.

My question is how do I go confirming the frequency of the T-Bolt
or the Efratom Rubidium?  The Efratom has an adjustment pot
to fine-tune its output frequency.  How do Time-Nutters go about
confirming the accuracy of frequency references such as my
T-Bolt or Efratom rubidium oscillator?

Thanks for any feedback / suggestions on this !!

Off-list communications on this via my email is OK!!

Mike Baker   mp...@clanbaker.org
Micanopy/Gainesville  North Central Florida
**

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[time-nuts] Re: Isotemp OCXO question

2021-08-21 Thread Robert DiRosario

This will just be a backup clock in my amateur radio station.  I already 
have a Truetime XL-DC and a XL-AK, both have GPS receivers that give 
IRIG-B and 1PPS outputs, and drive a couple of IRIG-B clocks.  I would 
guess the GPS time signal will be more accurate and precise then WWVB, 
and both will be more accurate and precise then my Heathkit Most 
Accurate Clock, which uses WWV.


To the human eye, as long as the seconds match on all sources, I'm 
happy.  On the other hand, for my GPS-NTP box and especially for my 
GPS-DO frequency standards, I want a lot better then 1 Hz.


I really wish NIST didn't add the BPSK modulation to WWVB. Increasing 
the transmitter power would have been a lot better, but I'm sure that 
would have cost a lot more then just changing the modulation.


Robert



On 08/19/2021 09:19 PM, Bob kb8tq wrote:

Hi

The issue you run into is that the fancy devices tried to derive information 
from
the phase of the WWVB signal. With an “AM only” receiver accuracy in the 10’s
(or 100’s … yikes ….) of ms was pretty common. With a phase oriented approach,
you could get into the 100’s of us. Indeed there is a lot of fine print 
involved with
any WWVB claims.

The change over did not impact the typical WWVB watch or an AM based receiver.
It very much messed up any of the fancy timing stuff.

Bob


On Aug 19, 2021, at 9:09 PM, Robert DiRosario  wrote:

I have a MAS6180C AM receiver chip, on a board with a few other parts to 
complete the receiver.  I did not make the board, it came from
Universal-Solder Electronics in Canada.  The date on the chip datasheet is 2014 
and on the receiver board 2016, so after NIST messed up WWVB in 2012.

Robert


On 08/19/2021 07:23 PM, Bob kb8tq wrote:

Hi

It’s a good bet that whatever the spec on that Isotemp OCXO, it’s way better in 
terms
of temperature and aging then the DS3231. Is it still on frequency (however 
many years
later …..) who knows ….

Many of the “time oriented” WWVB devices stopped working when they put in the 
new
modulation scheme. It’s a pretty good bet that this applies to the device you 
have.

Bob


On Aug 19, 2021, at 6:55 PM, Robert DiRosario  wrote:

I got a  Trak Systems "Time Code Translator" from ebay.  It's a 1U box with 
large LEDs for DOY and H/M/S that translates IRIG-A to NASA-36 time code.  I plan on 
using the case for my WWVB clock.

Unexpectedly it has an Isotemp OCXO in it, model OCXO59-11-2, frequency marked 
as 1.000 MHz  The Isotemp website is more or less dead, it has no information 
on it.  Does anyone have any information on this model, like how accurate it 
is?  It has only three wires, which I assume are power, ground and output, with 
no EFC input.

One thing that I'm sill note sure about is what to do when the receiver is not 
receiving WWVB.  I was thinking of using something like the DS3231 RTC module.  
If this OCXO is better, I may use it.

Thanks

Robert
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[time-nuts] Re: Isotemp OCXO question

2021-08-19 Thread Robert DiRosario

This is just a little "fun" project.  I"m sure any of my GPS receivers 
will be more accurate by several orders of magnitude.


So does anyone know how to "decode" the Isotemp model numbers, assuming 
there is some pattern to them?


Robert


On 08/19/2021 09:19 PM, Bob kb8tq wrote:

Hi

The issue you run into is that the fancy devices tried to derive information 
from
the phase of the WWVB signal. With an “AM only” receiver accuracy in the 10’s
(or 100’s … yikes ….) of ms was pretty common. With a phase oriented approach,
you could get into the 100’s of us. Indeed there is a lot of fine print 
involved with
any WWVB claims.

The change over did not impact the typical WWVB watch or an AM based receiver.
It very much messed up any of the fancy timing stuff.

Bob


On Aug 19, 2021, at 9:09 PM, Robert DiRosario  wrote:

I have a MAS6180C AM receiver chip, on a board with a few other parts to 
complete the receiver.  I did not make the board, it came from
Universal-Solder Electronics in Canada.  The date on the chip datasheet is 2014 
and on the receiver board 2016, so after NIST messed up WWVB in 2012.

Robert


On 08/19/2021 07:23 PM, Bob kb8tq wrote:

Hi

It’s a good bet that whatever the spec on that Isotemp OCXO, it’s way better in 
terms
of temperature and aging then the DS3231. Is it still on frequency (however 
many years
later …..) who knows ….

Many of the “time oriented” WWVB devices stopped working when they put in the 
new
modulation scheme. It’s a pretty good bet that this applies to the device you 
have.

Bob


On Aug 19, 2021, at 6:55 PM, Robert DiRosario  wrote:

I got a  Trak Systems "Time Code Translator" from ebay.  It's a 1U box with 
large LEDs for DOY and H/M/S that translates IRIG-A to NASA-36 time code.  I plan on 
using the case for my WWVB clock.

Unexpectedly it has an Isotemp OCXO in it, model OCXO59-11-2, frequency marked 
as 1.000 MHz  The Isotemp website is more or less dead, it has no information 
on it.  Does anyone have any information on this model, like how accurate it 
is?  It has only three wires, which I assume are power, ground and output, with 
no EFC input.

One thing that I'm sill note sure about is what to do when the receiver is not 
receiving WWVB.  I was thinking of using something like the DS3231 RTC module.  
If this OCXO is better, I may use it.

Thanks

Robert
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[time-nuts] Re: Isotemp OCXO question

2021-08-19 Thread Robert DiRosario

I have a MAS6180C AM receiver chip, on a board with a few other parts to 
complete the receiver.  I did not make the board, it came from
Universal-Solder Electronics in Canada.  The date on the chip datasheet 
is 2014 and on the receiver board 2016, so after NIST messed up WWVB in 
2012.


Robert


On 08/19/2021 07:23 PM, Bob kb8tq wrote:

Hi

It’s a good bet that whatever the spec on that Isotemp OCXO, it’s way better in 
terms
of temperature and aging then the DS3231. Is it still on frequency (however 
many years
later …..) who knows ….

Many of the “time oriented” WWVB devices stopped working when they put in the 
new
modulation scheme. It’s a pretty good bet that this applies to the device you 
have.

Bob


On Aug 19, 2021, at 6:55 PM, Robert DiRosario  wrote:

I got a  Trak Systems "Time Code Translator" from ebay.  It's a 1U box with 
large LEDs for DOY and H/M/S that translates IRIG-A to NASA-36 time code.  I plan on 
using the case for my WWVB clock.

Unexpectedly it has an Isotemp OCXO in it, model OCXO59-11-2, frequency marked 
as 1.000 MHz  The Isotemp website is more or less dead, it has no information 
on it.  Does anyone have any information on this model, like how accurate it 
is?  It has only three wires, which I assume are power, ground and output, with 
no EFC input.

One thing that I'm sill note sure about is what to do when the receiver is not 
receiving WWVB.  I was thinking of using something like the DS3231 RTC module.  
If this OCXO is better, I may use it.

Thanks

Robert
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[time-nuts] Isotemp OCXO question

2021-08-19 Thread Robert DiRosario

I got a  Trak Systems "Time Code Translator" from ebay.  It's a 1U box 
with large LEDs for DOY and H/M/S that translates IRIG-A to NASA-36 time 
code.  I plan on using the case for my WWVB clock.


Unexpectedly it has an Isotemp OCXO in it, model OCXO59-11-2, frequency 
marked as 1.000 MHz  The Isotemp website is more or less dead, it has no 
information on it.  Does anyone have any information on this model, like 
how accurate it is?  It has only three wires, which I assume are power, 
ground and output, with no EFC input.


One thing that I'm sill note sure about is what to do when the receiver 
is not receiving WWVB.  I was thinking of using something like the 
DS3231 RTC module.  If this OCXO is better, I may use it.


Thanks

Robert
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[time-nuts] GPS antenna question

2021-07-22 Thread Robert DiRosario

If I want to use GPS for time and frequency standards, just how solidly 
does the antenna need to be mounted?
The easiest and least expensive way to mount a GPS antenna would be up 
on two 10' TV mast sections, but that
would move around a bit in the wind.  Maybe two or three inches.  Or do 
I need to do better?  All of the "easy" or

"good" spots in my yard already have amateur radio antennas.

A second question, and it may very between different GPS receivers, how 
to they get the time?  Do they just take one signal
with a good S/N number and correct for the distance from that satellite, 
or do something more complicated with several signals?


Thanks
Robert
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[time-nuts] Re: Thunderbolts ...

2021-07-19 Thread Robert DiRosario


I found this on ebay from Chine:

Trimble 10MHz ThunderBolt GPS Disciplined Clock GPSDO Module Frequency 
Standard

https://www.ebay.com/itm/332390729098?
US $197.00 or make offer.  He does take lower offers.

He also lists:
Power Supply & Antenna FOR Trimble 10MHz ThunderBolt GPS Disciplined 
Clock GPSDO

https://www.ebay.com/itm/332786802886?
US $55.00

Both have free shipping.

I purchased both, they just arrived.  It looks good, I need to test it, 
once I find another outlet strip for my

time-nuts setup.

Other sells have it for more.  No US sellers.

Robert

On 07/16/2021 07:06 PM, Dave wrote:

I'm a bit of a newbie at this, but is it possible to buy thunderbolts ??

If so, where ?

Regards,
Dave

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[time-nuts] Datum Starloc II

2021-07-10 Thread Robert DiRosario


A seller in Canada has new Datum Starloc II GPSDO's for sale:

https://www.ebay.com/itm/17417494?epid=27027611062&hash=item288d9969d2:g:iCQAAOSwhexcL780

I found this thread on them from June 2016:
https://time-nuts.febo.narkive.com/v0pxiqAL/datum-starloc-ii-gpsdo-issues

They seem to be a pain to use, are they any better then the Trimble 
Thunderbolts?


Thanks
Robert
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[time-nuts] Re: TimeHat

2021-07-05 Thread Robert DiRosario

I'll post this so people know what the problem was.  I forgot the older 
Raspberry Pi's are 32 bit.  I looked in my junk box and found a pair of 
"Raspberry Pi Model B+", old 32 bit systems.  It works fine with the 64 
bit code on a 64 bit Raspberry Pi 3B.


Robert


On 07/05/2021 07:01 PM, John Miller via time-nuts wrote:

Curious…. feel free to reach out to me directly and I can send you the TimeHat 
image and you can re-flash it. For what it’s worth, the cards I all sent out 
initially were 64bit, so the would only work on the Pi2 and newer. If you want 
to run it on a first gen Pi or a Zero-W, you need the 32 bit image, and I have 
that as well.

Regards,
John


On Jul 5, 2021, at 4:16 PM, Robert DiRosario  wrote:

After more checking I do get video out, but it's blank. The keyboard and mouse 
don't work.  The Ethernet link is never activated.  If I stick a memory card 
with a valid OS in the system comes up just fine and everything works, video, 
keyboard and mouse and Ethernet.  So it's not a hardware problem with the 
Raspberry Pi or the TimeHat.

If I put a blank memory card in then I get no video output.  At first it looks 
the same as what the TimeHat memory card is doing, but if I go into the menu on 
the monitor there is a difference.

Robert


On 07/05/2021 07:04 AM, John Miller via time-nuts wrote:

Robert,
If an HDMI display is connected when the board is booted, video should be 
displayed. If no display is connected when the system is booted, the HDMI port 
is not activated, and you cannot attach a monitor to it after the fact.

If this is something you and others would like to do, I can work out a method 
to reconfigure it such that video is output all the time. Just keep in mind 
this will take consume some system resources and add some CPU overhead.

Regards,
John


On Jul 5, 2021, at 12:23 AM, Robert DiRosario  wrote:

On the Raspberry Pi TimeHat is there output to the HDMI connector, or is it 
configured to just use a serial console?
I'm using the preconfigured SDHC card, so the software should be fine.  If I 
swap out the SDHC card with a different one the systems boots fine, so the 
hardware works.

With the card with the software there is never any output to the HDMI connector.

Based on the LED on the GPS module it's locking up on the GPS signals just 
fine.  After the initial lockup, it locks up again in only a few seconds after 
a power cycle.

Robert
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[time-nuts] Re: TimeHat

2021-07-05 Thread Robert DiRosario

After more checking I do get video out, but it's blank. The keyboard and 
mouse don't work.  The Ethernet link is never activated.  If I stick a 
memory card with a valid OS in the system comes up just fine and 
everything works, video, keyboard and mouse and Ethernet.  So it's not a 
hardware problem with the Raspberry Pi or the TimeHat.


If I put a blank memory card in then I get no video output.  At first it 
looks the same as what the TimeHat memory card is doing, but if I go 
into the menu on the monitor there is a difference.


Robert


On 07/05/2021 07:04 AM, John Miller via time-nuts wrote:

Robert,
If an HDMI display is connected when the board is booted, video should be 
displayed. If no display is connected when the system is booted, the HDMI port 
is not activated, and you cannot attach a monitor to it after the fact.

If this is something you and others would like to do, I can work out a method 
to reconfigure it such that video is output all the time. Just keep in mind 
this will take consume some system resources and add some CPU overhead.

Regards,
John


On Jul 5, 2021, at 12:23 AM, Robert DiRosario  wrote:

On the Raspberry Pi TimeHat is there output to the HDMI connector, or is it 
configured to just use a serial console?
I'm using the preconfigured SDHC card, so the software should be fine.  If I 
swap out the SDHC card with a different one the systems boots fine, so the 
hardware works.

With the card with the software there is never any output to the HDMI connector.

Based on the LED on the GPS module it's locking up on the GPS signals just 
fine.  After the initial lockup, it locks up again in only a few seconds after 
a power cycle.

Robert
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[time-nuts] TimeHat

2021-07-04 Thread Robert DiRosario

On the Raspberry Pi TimeHat is there output to the HDMI connector, or is 
it configured to just use a serial console?
I'm using the preconfigured SDHC card, so the software should be fine.  
If I swap out the SDHC card with a different one the systems boots fine, 
so the hardware works.


With the card with the software there is never any output to the HDMI 
connector.


Based on the LED on the GPS module it's locking up on the GPS signals 
just fine.  After the initial lockup, it locks up again in only a few 
seconds after a power cycle.


Robert
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[time-nuts] Re: Z3801A Receiver Replacement

2021-06-22 Thread Robert DiRosario


Does this effect All Z3801As?
I have one of these:
http://www.realhamradio.com/GPS_Frequency_Standard.htm
I picked up a power supply and antenna for it but  haven't done anything 
with it yet.


> I have a HP Z3801A with a dead GPS receiver.
Is it dead because of Week-Roll over limits or something else?

Robert


On 06/21/2021 11:54 PM, Art Sepin wrote:

Hi Fred,

I apologize if the following smells overtly commercial; it's only intended to 
answer your questions and explain where we are in the process of producing GPS 
replacement products for legacy timing instruments.

The 6 and 8 channel Motorola VP and 8 channel UT+ will not work as 
replacements. Those products have also reached their 1024 Week-Roll Over 
limits. The HP Z3801A and Z3805A products only respond to 6 channel commands 
and produce 6 channel reply messages.

We have developed single-board clones for the Motorola VP and UT+ products, as 
drop-in replacements, that are lower in cost than Synergy's 2-board Adaptor 
Board products (Shooting for dropping to less than $190 if component prices 
don't go even higher!). The SSR-VP can plug into the HP Z3801A and Z3805A 
products.

A different part number SSR-VP designed to drop into HP 58503A and an SSR-UT+, 
designed to drop into HP 58503B products, have also been completed but firmware 
for those have yet to be tested in actual instruments. With the proper firmware 
loads, the SSR Drop-In products should be candidates for upgrading many other 
legacy timing instruments.

We had planned for the single board "Drop-In" products to be available near the 
end of 2020 but COVID-19 changed things for us. We are now planning a small production 
run to satisfy folks that have already been in touch with us but we need to complete our 
boot-loader for firmware updates first. With current work load, I'd estimate 90 - 120 
days for HP Z3801A and Z3805A replacements. If you are interested we can put you on our 
list.

Apologies for the quasi-commercial intrusion!

Art


-Original Message-
From: Frederick Bray 
Sent: Monday, June 21, 2021 7:21 PM
To: time-nuts@lists.febo.com
Subject: [time-nuts] Z3801A Receiver Replacement

I have a HP Z3801A with a dead GPS receiver.  I understand that it is possible 
to drop in an Oncore VP 8 channel receiver as a replacement -- not withstanding 
the fact that the Z3801A will only see six channels.

I see that Motorola R5122U1154 8 channel receivers are available.  Does anyone 
know whether this will function in the Z3801A?  I'd like to get it working 
again.

Thanks.

Fred Bray, KE6CD



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[time-nuts] Re: Trak 8812 Station Clock

2021-06-16 Thread Robert DiRosario


The manual for the Trak 8820 is at:

http://www.to-way.com/tf/trak8820a.pdf

I don't know if it will be of any use.

Robert

KA3ZYX


On 06/16/2021 12:59 PM, Roland Ude wrote:


 I just acquired two each 8812 Station Clocks. I am looking for 
operating manuals, command structure, and supporting information. I've 
powered up the first unit - achieved lock but has roll over issues. 
All help and support information is greatly appreciated.


Buzz W8BUZ, buzz at baylorhill.com or 937-605-4951.



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[time-nuts] Re: 2nd Run of TimeHats

2021-06-15 Thread Robert DiRosario

I'll take one unit and, depending on the price, a second board (only) or 
a full unit.


Robert


On 04/26/2021 08:32 AM, John Miller via time-nuts wrote:

Hello everyone,

I’ve seen a number of messages lately that reference the TimeHat boards I put 
together a couple of months ago, with lots of positive feedback, which I really 
appreciate. The first run of boards I did sold fairly quickly, and based on a 
number of emails I have gotten lately there seems to be some renewed interest.

As such, I’m going to order up another batch of PCBs and parts, but I’d like to 
get an idea of how many I need to order to satisfy current demand. The GPS 
modules come from China, so there is about a two or three week wait them, so I 
want to make sure I have enough.

For those not familiar, you can learn more about the TimeHat here:
https://millerjs.org/timehat

Regards,
John
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[time-nuts] Test

2021-06-14 Thread Robert DiRosario


Test message,

I've seen no new messages in the past 5 days.  Just checking if things 
are working.

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[time-nuts] ThunderBolt question

2020-06-05 Thread Robert DiRosario

I have a Trimble ThunderBolt GPSDO that I just received. It has an F 
connector for the antenna input, and BNC connectors for the 1 pps and 10 
MHz outputs. Is the receiver input impedance really 75 Ohms, or is it 50 
Ohms and they just used the F connector to distinguish it from the 
others? What do people do, just use a 50 Ohm antenna?


Thanks

Robert DiRosario

KA3ZYX

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Re: [time-nuts] GPS antenna splitter recommendation?

2020-04-30 Thread Robert DiRosario

I just went on ebay.  I got one of the 8 port units with 5V antenna 
power supply and 11 db amp, there is still one left $175.00


https://www.ebay.com/itm/GPS-SOURCE-S18-A11-P110-5-GPS-1x8-WAY-SPLITTER-DEVICE-LOOK-REF-233G/193397441449?hash=item2d0762c3a9:g:PQIAAOSw0eNdDSLi

Here it is in the catalog at $1064.   $175 used looks like a very 
good price!


https://www.gpssource.com/products/s18-1x8-standard-gps-splitter?variant=10811989699

Here is a passive 4 port for $100.00 (9 available)
https://www.ebay.com/itm/GPS-Source-1x4-Stamdard-Amplified-Splitter-S14-S14S-E-SF/401835679864?hash=item5d8f45e078:g:pkYAAOSwfe5dRKrq

And this seller also has a active 4 port, also for $100. (1 available)
https://www.ebay.com/itm/GPS-Source-1x4-Standard-Amplified-Splitter-S14-S14S-A-E-HS-SF/401835678023?hash=item5d8f45d947:g:zOcAAOSwcyNdRKns

And this one has a 4 port passive for $80
https://www.ebay.com/itm/GPS-Source-1x4-4-Way-Splitter-Slimline-PN-S14S-SF/124166494822?hash=item1ce8e65a66:g:aPkAAOSwXZBepQkG

A couple in Israel also show up.

I just did a search on "gps source".
Someone has a 10 dB GPS attenuator for $100.  At 1.5 GHz some RG-58 will 
do that for a lot less money!! :-)


Robert


On 04/30/2020 04:13 AM, Larry McDavid wrote:
Frank, I'm using a GPS Source S14WI 4-way GPS splitter. Mine has  > options for 20 dB amplification, Bias Select (how power is passed > 
back to the antenna), Antenna Monitor and N Female connectors. These > 
are very rugged, sealed units. They turn up on eBay from time to > time; 
I was fortunate to find several offered as New Old Stock. I > will 
attach (I hope) a data sheet. > > Any splitter without amplification 
will have reduced antenna signal > to each output. If you will have a 
long coax run from the antenna to > the splitter as I do, use of an 
amplified spiltter will prevent > further loss within the splitter. > > 
I also have a Symmetricon 58517A 8-way GPS splitter. This model has a > 
unity gain amplifier ahead of the splitter so the gain to each output > 
is specified as ±4 dB. A data sheet is attached. These also turn up > on 
eBay. > > Passive splitters offered on eBay are sometimes not GPS 
splitters but > passive satellite TV splitters. If the price is low, 
suspect a > satellite TV splitter. These also typically have poor 
isolation > port-to-port. > > My GPS antenna is located atop my roof, in 
the clear with > horizon-to-horizon view and fed with 5/8-inch Heliax 
flexible hard > line down to the splitter. > > Four-way splitters are 
likely most common, with 8-way next. I've > never seen a 3-way splitter. 
> > Larry > > On 4/29/2020 5:18 PM, Frank O'Donnell wrote: >> I'm 
looking for a splitter to allow three or four GPSDO's to share >> my 
roof-mounted Lucent PCTEL KS24019L112C 26db GPS twist antenna. >> >> I 
understand from scanning past threads that inexpensive splitters >> by 
companies like Mini-Circuits often turn up on eBay, but I'm >> having 
trouble narrowing down to one that will work for my >> situation. Can 
anyone recommend a specific splitter that wouldn't >> be too expensive? 
>> >> Thanks much, >> >> Frank >> >> >> 
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Re: [time-nuts] Vaperware Parts and pulse stretching circuits

2020-04-26 Thread Robert DiRosario

You can also get it from Universal-solder in Canada:

ebay:
https://www.ebay.com/itm/Real-Time-Clock-DS3231SN-for-Arduino-32kB-EEPROM-I2C-Battery-Backup/263183091193

C $4.92 Approximately US $3.49

Or from the web site:
https://www.universal-solder.ca/product/rtc-real-time-clock-ds3231-32kb-eeprom-i2c-interface-cr2032-arduino/
CAD 4.56

Unlike Adafruit, in NYC, Universal-solder, in Canada, is open.

I have one on the way.

I've bought stuff from them before, no problems, same for Adafruit.

Robert

On 04/25/2020 01:04 PM, Ben Bradley wrote:

Adafruit and Sparkfun sell a remarkable number of SMT parts already on
breakout boards for moderate prices. I looked up the three parts and
found the DS3231 on a board (two different boards even), in stock and
ready to order from Adafruit (most Adafruit and Sparkfun products are
also sold through Digikey):
https://www.adafruit.com/?q=DS3231

These links bring up the others, each site has hundreds:
https://www.adafruit.com/?q=breakout

https://www.sparkfun.com/search/results?term=breakout

On Fri, Apr 24, 2020 at 7:47 PM John Ackermann N8UR wrote:

Hi Perry --

The circuit in the FatPPS is really simple and would be easy to duplicate.

Frankly, the reason we had to significantly increase the cost is because
we provide the board fully assembled (it's all surface mount parts), and
with the low volume we've had in the last few years, the per-unit
assembly cost has gone way up.

John

On 4/24/20 7:19 PM, Perry Sandeen via time-nuts wrote:

Learned Gentlemen,
Several poster wrote:
TAPR offers a FatPPS kit to stretch the pulse out, and it looks likethey're
back in stock. I have one but haven't assembled it
yet.https://tapr.org/product/fatpps-pulse-stretcher/
OK no problemo. But it's $55. It's probably a great device, but does this
application warrant such expense?
I looked up *pulse stretcher circuits* and found over a dozen inexpensive
circuits.

DRV8662and is available from Digikey for $3.35. It is a small-pitch
device(0.5mm) but not impossible to solder.

RV-3028 is 3.2x1.5 mm in size, 1.5ppm, additionally trimmable, 45 nAstandby
current, under $3 USD in price and in stock at Mouser andDigikey.

Aswonderful as the DS3231 is, there is a newer chip from Micro Crystalthat is
smaller, more accurate than the DS3231M, much cheaper, anddraws less power

These three chips fall into the *Vaperware Parts* category. Yes, they are great
chips and I don't mind someone posting their advantages.
I believe It is a bit disingenuous to say: *It is a small-pitch device but not
impossible to solder*.
Really? If you've dropped $750 to $1K for a stereo microscope and other
specialized soldering equipment then you can probably do it without too much
difficulty. Or some may access to such specialized equipment.
But for us *Po Folks* hobbyist we have to stick with older but larger parts.
Now if there was a service where you could order the part soldered to a
breakout board with .1 inch breakout pins for say, $20 then using many of the
latest chips would be feasible. But until then I believe 99.9 percent of us
have to find a commercial product or some other workaround.
Regards,
Perrier

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Re: [time-nuts] Connector options for HP10811A?

2020-04-10 Thread Robert DiRosario

Have you used the Mouser part you listed? When you look at the spec
sheet it only shows 8 of the 15 pins installed in the connector.

https://www.mouser.com/datasheet/2/123/307-030-520-201_-_EDAC_Card_Edge_Connector-1653445.pdf

I have used this, and it show all the pins installed:

https://www.mouser.com/datasheet/2/123/305-030-500-202_-_EDAC_Card_Edge_Connector-1652975.pdf

Graham / KE9H listed:

https://www.mouser.com/datasheet/2/123/306-015-500-102_-_EDAC_Card_Edge_Connector-1653038.pdf

which also shows all of the pin installed.

Why would they not install all of the pins? If they do install all of
them why do they show some missing, when they show them installed on the
other two products? I would like to use the through hole pins socket.

Robert, KA3ZYX

On 04/08/2020 10:06 PM, Bob kb8tq wrote:

The connector is a very normal 2 x 15 position 0.156” spaced edge connector.
You can buy them on Amazon:

https://www.amazon.com/gp/product/B0721L5VSD/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

From Mouser:

https://www.mouser.com/ProductDetail/587-307-030-520-201

From various people on eBay:

https://www.ebay.com/itm/Card-edge-connector-row-30-Pin-3-96mm-pitch-805-slot-solder-PCB-2x15-socket-NMGG/293411808673?ssPageName=STRK%3AMEBIDX%3AIT&var=592241315857&_trksid=p2057872.m2749.l2649

https://www.ebay.com/itm/TRW-Cinch-Connector-252-18-30-301-Lot-of-6/122819145572?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

( ummm …. errr …. no, not that last one, it’s 18 pin … I only counted the pins
*after* they got here :) )

or from a variety of other sources.

If you dig a bit there is even a guy selling the full adapter for the 10811,
(for a crazy price) but not identifying it
as working with the 10811

Bob

On Apr 8, 2020, at 9:39 PM, Frank O'Donnell wrote:

I recently bought an HP10811A oscillator on eBay, only belatedly realizing that
it's designed to interface to a 15-contact connector that the manual identifies
as a CINCH 250-15-30-210 or equivalent.

A search turns up a vendor in Massachusetts called BMI Surplus Inc., that
appears to have these in stock in new condition at a minimal price. The only
hitch is that BMI's website says they're closed down due to COVID-19 and will
not process any orders until their state government authorizes businesses to
return. (And at this point, it's anyone's guess when that will be.)

To get going with the oscillator, it occurs to me that I could rig up a few
small alligator clips and use them on the required contacts for the time being.
Any other thoughts or suggestions on how to work this? By any chance are there
other known sources for the right size of connector that might be operating
right now?

Thanks much,

Frank O'Donnell
South Pasadena, California

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Re: [time-nuts] Connector options for HP10811A?

2020-04-10 Thread Robert DiRosario


I just ordered some from Mouser in November, this is it:

https://www.mouser.com/ProductDetail/587-305-50-030

They list 41 in stock, for 1 to 9 the price is $8.43

Robert


On 04/08/2020 09:39 PM, Frank O'Donnell wrote:
I recently bought an HP10811A oscillator on eBay, only belatedly 
realizing that it's designed to interface to a 15-contact connector 
that the manual identifies as a CINCH 250-15-30-210 or equivalent.


A search turns up a vendor in Massachusetts called BMI Surplus Inc., 
that appears to have these in stock in new condition at a minimal 
price. The only hitch is that BMI's website says they're closed down 
due to COVID-19 and will not process any orders until their state 
government authorizes businesses to return. (And at this point, it's 
anyone's guess when that will be.)


To get going with the oscillator, it occurs to me that I could rig up 
a few small alligator clips and use them on the required contacts for 
the time being. Any other thoughts or suggestions on how to work this? 
By any chance are there other known sources for the right size of 
connector that might be operating right now?


Thanks much,

Frank O'Donnell
South Pasadena, California





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Re: [time-nuts] Synchronisation of crystal oscillators

2020-03-10 Thread Robert DiRosario

>  OTOH, if you carefully
>adjust a couple of HP10811's to zero beat, you will have to
>go to extraordinary measures to keep them from injection locking.
>A lot more than just running them on individual voltage
>regulators.

How are they connected, or coupled?  They seem to be well shielded, do 
you tie the

outputs together?  Don't they have a transistor buffer stage on the output?

Robert

On 03/01/2020 05:46 PM, Richard (Rick) Karlquist wrote:

On 3/1/2020 2:28 PM, John Moran, Scawby Design wrote:
My apologies if this is slightly off-topic, but it does concern 
crystal oscillators.

However, I then remembered Huygens's discovery that 1S pendulums 
mounted on the same wall, or beam, would synchronise and swing 
either in phase, or out of phase and sometimes one would be stopped, 
by the minute interactions.

So, my question is - will my row of low frequency crystals 'talk' to 
each other and synchronise in their frequency groups as well? 
Remember that these crystals are long thin bars of quartz - one of 
the 3,600Hz crystals being 2mm square by 60mm long - so they will 
possibly vibrate quite vigorously compared w

Injection locking requires that the oscillators be within each
others 3 dB bandwidth, or at least close to that.  Oscillators
on different nominal frequencies are no problem (EG 3 MHz and
10 MHz).  Even two "10 MHz" oscillators won't lock unless they
are adjusted to close to zero beat.  OTOH, if you carefully
adjust a couple of HP10811's to zero beat, you will have to
go to extraordinary measures to keep them from injection locking.
A lot more than just running them on individual voltage
regulators.

Bottom line: probably not worth worrying about for your
hobby project.

Rick N6RK

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Re: [time-nuts] HP 5335A and using the HPIB for control

2020-03-05 Thread Robert DiRosario

> he said that any HPIB controls would involve some programming which 
is impossible to do.
What??? As a software developer for 30+ years I have a major problem 
with that!!
I have done HPIB programming before, it's not very hard.  What type of 
programming was he talking about?


I'm setting up my own "time lab" right now.  I just got a HP 5370A and a 
HP 5335A.
I already have a 5334A, 5334B and a pair of 5385As, and a NI PCI HPIB 
card that I just put in a Linux box.
I plan on using the card to collect data from the counters. Starting 
with logging measurements.
I don't know if any of my counters support reading while actively 
counting.  (Reading and clearing the counter

while the gate is open and it's actively counting.)

Do other "time-nuts" make use of HPIB?

Robert


On 03/04/2020 03:28 PM, Perry Sandeen via time-nuts wrote:

Learned Gentlemen,
While my TN stuff is packed for moving, I took a look at the HP 5335 spec sheet.
It appears that the gate time can be extended up to 10^7 seconds which would be 
very useful.
Talking with Bob Camp off list he said that any HPIB controls would involve 
some programming which is impossible to do. There is a labview home program for 
about $100 but that would also require some programing.

I could make extended gate times by making a 1PPS from my 10MHz reference and 
using it for the external gate start and counting it to get my desired stop 
time or perhaps there is the possibility of doing an internal mod to the 
counter which if it wouldn't be fairly simple, I'd rather not try.
Does anyone know of or have a program that I could put on a laptop (windoz) to 
control the gate time function?  For several reasons at this time  buying 
something newer like a HP53131 or equivalent to accomplish this is not feasible.
Thoughts?
Regards,
Perrier






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Re: [time-nuts] Frequency standards for different tau in Allen Dev measurement

2020-02-23 Thread Robert DiRosario via time-nuts

SDRs (Software Defined Radio) decimate / downsample.  Look at SDR 
documentation.


Google turns up: https://dspguru.com/dsp/faqs/multirate/decimation/

Robert

On 02/21/2020 03:09 PM, Gary E. Miller via time-nuts wrote:

Yo Magnus!

On Fri, 21 Feb 2020 20:33:46 +0100
Magnus Danielson via time-nuts  wrote:


As one decimate data, one needs to be very very careful with
bandwidth. It would make biases in values which would over-state
stability. Yes, we have seen it happen. Even big names has come clean
and confessed doing it wrong when they decimated the data.

Anyone have any references to how to decimate properly?

RGDS
GARY
---
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
g...@rellim.com  Tel:+1 541 382 8588

Veritas liberabit vos. -- Quid est veritas?
 "If you can't measure it, you can't improve it." - Lord Kelvin


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Re: [time-nuts] 10811 performance

2020-01-05 Thread Robert DiRosario

We have four HP distribution amps.  Most of the line distribution cards 
are 1 and 5 MHz, some 100 KHz and a few 10 MHz.


As for the power use by the 10811 oscillators when the equipment is 
turned off but still plugged in, we are at a government facility with 
almost 40 major buildings.  Nothing we can do in our three little ex 
FEMA trailers could show up on the electric meter, even if we tried.


The fun part will be at home, where I try to test the different 
standards, using the test equipment I have.


Robert


On 01/05/2020 02:09 PM, Bob kb8tq wrote:

Hi

The simple answer is that a ~ $100 Chinese GPSDO and a ~ $20 MiniCircuits power 
splitter
(all off of eBay) should be able to drive a couple of counters and a few other 
pieces of gear.

If they are all “power on” when the bench is in use, daisy chain from the 
“important” stuff to
the less accurate gear is fine. Indeed this adds to the maintenance checks 
while reducing the
cost of the distribution hardware. ( = no free lunch).

For normal lab use, the GPSDO output will do fine and it will be more accurate 
than normal
bench gear. There’s also the “cool kid” factor :). The 10 MHz output can be 
provided for members
to cal their gear against.

One advantage of the GPSDO approach is that the rest of the bench can be fully 
shut down
when nobody is around. A simple timer could do the job without anybody needing 
to remember
this or that switch.

The power savings from shutting the bench down fully will easily pay for the 
GPSDO in under
a year …..

Bob


On Jan 5, 2020, at 1:29 PM, Robert DiRosario  wrote:

I'm back, sorry for the delayed response.

My understands is in the HP 5340A counter (all HP counters?) the 10544 or 10811 
always has  power, regardless  of the power switch, as long as it is plugged 
in.  Everything at our work bench is always plugged in.

History
We (the radio club) have three HP 5340A counters, two 5345A counters and an HP 
106B.  We took one of the 5340As and the 106B to the building with the Cs 
standard in a minivan with a 12V to 120V inverter.  The 106B had a good battery 
pack, but it was still powered with the inverter.  The first test was to put 10 
MHz from the Cs standard into the counter, and it read 1000. MHz.  We moved 
on to plan B, we put the output of the OCXO into a counter what was driven by 
the Cs standard.  The error was less then 0.1 Hz.  We made a little change to 
the 10811 and moved on to the 106.  The error on the 5 MHz output was again 
less than 0.1 Hz, we made a small change to it.  We ate our lunch and moved the 
counter cable back and forth between the 5340A and 106B and watched them. They 
both stabilized.  20 years latter, I don't recall what the final error was.  It 
was much better than any piece of ham gear anyone would have.

In 2011 the club got relocated to three mobile home trailers. They have HVAC 
wall-packs, so we have Heat and AC 24/7 year-round.
Before the move the HVAC in the one room building that housed our work bench 
and VHF station stopped working.  The 106 also stopped working.  I started 
looking at a GPSDO after the move.  I picked up some 10811s and Navman Jupiter 
TU modules with 10 KHz output, but other projects came along and I lost 
interest in this.

Today:
This fall at a hamfest I got a working TrueTime XL-DC with antenna and feedline 
for $45, it has 1 ppp and IRIG-B, but no 10 MHz output.  This restarted my 
interest in this project.  Then I got some complaints from other club members 
that our HP Modulation Analyzer was both off frequency and the deviation 
measurement it was giving was also wrong.

The first goal is to have fun and learn something new.

At the club we  have 3 5340As (18 GHz), the 53131A (225 MHz), a pair of 5435As 
that don't work, and the 106B that doesn't work.
The goal is to have a calibrated standard to drive all of our test equipment.  
It should be accurate and precise enough to allow club members to calibrate 
their own equipment.  That would point to a GPSDO.  A 10811 for start, the 106 
if I can fix it.

At home I have several HP counters, 5340A (18 GHz), 5341A (4.5 GHz), 5385A (1 
GHz), 5386A (3 GHz) and a 5334B (100 MHz, dual channel, sill do TI), but none 
are calibrated.  I have a NI HPIB card I need to get working.  I have a HP 
Z3801A that I need to get a power supply for.  I have several 10811s, a pair of 
105Bs, a Trimble 57963 board, and the simple complete Trimble 57963 system.  I 
also have a Brooks Shera board that is built, I have some connectors for it on 
the way.

I have a full set of time-nut toys to play with!  My view is I have no known 
working primary standards yet, so I'm starting from scratch.
I need to compare the Trimble GPSDO to something else.  The Z3801A or Brooks 
Shera's board controlling a 10811 or one of the 105Bs.

Thanks

Robert

On 12/26/2019 11:51 PM, Robert DiRosario wrote:

I am trying to calibrate some equipment at the amateur radio club at work, and 
my stuff.  We

Re: [time-nuts] 10811 performance

2020-01-05 Thread Robert DiRosario


I'm back, sorry for the delayed response.

My understands is in the HP 5340A counter (all HP counters?) the 10544 
or 10811 always has  power, regardless  of the power switch, as long as 
it is plugged in.  Everything at our work bench is always plugged in.


History
We (the radio club) have three HP 5340A counters, two 5345A counters and 
an HP 106B.  We took one of the 5340As and the 106B to the building with 
the Cs standard in a minivan with a 12V to 120V inverter.  The 106B had 
a good battery pack, but it was still powered with the inverter.  The 
first test was to put 10 MHz from the Cs standard into the counter, and 
it read 1000. MHz.  We moved on to plan B, we put the output of the 
OCXO into a counter what was driven by the Cs standard.  The error was 
less then 0.1 Hz.  We made a little change to the 10811 and moved on to 
the 106.  The error on the 5 MHz output was again less than 0.1 Hz, we 
made a small change to it.  We ate our lunch and moved the counter cable 
back and forth between the 5340A and 106B and watched them. They both 
stabilized.  20 years latter, I don't recall what the final error was.  
It was much better than any piece of ham gear anyone would have.


In 2011 the club got relocated to three mobile home trailers. They have 
HVAC wall-packs, so we have Heat and AC 24/7 year-round.
Before the move the HVAC in the one room building that housed our work 
bench and VHF station stopped working.  The 106 also stopped working.  I 
started looking at a GPSDO after the move.  I picked up some 10811s and 
Navman Jupiter TU modules with 10 KHz output, but other projects came 
along and I lost interest in this.


Today:
This fall at a hamfest I got a working TrueTime XL-DC with antenna and 
feedline for $45, it has 1 ppp and IRIG-B, but no 10 MHz output.  This 
restarted my interest in this project.  Then I got some complaints from 
other club members that our HP Modulation Analyzer was both off 
frequency and the deviation measurement it was giving was also wrong.


The first goal is to have fun and learn something new.

At the club we  have 3 5340As (18 GHz), the 53131A (225 MHz), a pair of 
5435As that don't work, and the 106B that doesn't work.
The goal is to have a calibrated standard to drive all of our test 
equipment.  It should be accurate and precise enough to allow club 
members to calibrate their own equipment.  That would point to a GPSDO.  
A 10811 for start, the 106 if I can fix it.


At home I have several HP counters, 5340A (18 GHz), 5341A (4.5 GHz), 
5385A (1 GHz), 5386A (3 GHz) and a 5334B (100 MHz, dual channel, sill do 
TI), but none are calibrated.  I have a NI HPIB card I need to get 
working.  I have a HP Z3801A that I need to get a power supply for.  I 
have several 10811s, a pair of 105Bs, a Trimble 57963 board, and the 
simple complete Trimble 57963 system.  I also have a Brooks Shera board 
that is built, I have some connectors for it on the way.


I have a full set of time-nut toys to play with!  My view is I have no 
known working primary standards yet, so I'm starting from scratch.
I need to compare the Trimble GPSDO to something else.  The Z3801A or 
Brooks Shera's board controlling a 10811 or one of the 105Bs.


Thanks

Robert

On 12/26/2019 11:51 PM, Robert DiRosario wrote:
I am trying to calibrate some equipment at the amateur radio club at 
work, and my stuff.  We have an HP 5340A with a 10811 inside. It must 
have been upgraded at some point in the past, the display uses Nixie 
tubes.  I calibrated it c2000 using a HP Cs standard. That lab and 
it's equipment are gone.  :-(


From ebay / China I got a simple GPSDO that uses a Trimble 57963 
inside.  I use the output of the 10811 in the 5340A to drive an HP 
53131A.  I then measured the 10 MHz output of the GPSDO using the HP 
53131A and got 10,000,000.08 Hz.


Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a 
reasonable amount of drift for an 10811?


I have an HP Z3801A, once I get a power supply for it I can check the 
other GPSDO.


Thanks

Robert
KA3ZYX

______


On 12/26/2019 11:51 PM, Robert DiRosario wrote:
I am trying to calibrate some equipment at the amateur radio club at 
work, and my stuff.  We have an HP 5340A with a 10811 inside. It must 
have been upgraded at some point in the past, the display uses Nixie 
tubes.  I calibrated it c2000 using a HP Cs standard. That lab and 
it's equipment are gone.  :-(


From ebay / China I got a simple GPSDO that uses a Trimble 57963 
inside.  I use the output of the 10811 in the 5340A to drive an HP 
53131A.  I then measured the 10 MHz output of the GPSDO using the HP 
53131A and got 10,000,000.08 Hz.


Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a 
reasonable amount of drift for an 10811?


I have an HP Z3801A, once I get a power supply for it I can check the 
other GPSDO.


Thanks

Robert
KA3ZYX

___
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[time-nuts] 10811 performance

2019-12-27 Thread Robert DiRosario

I am trying to calibrate some equipment at the amateur radio club at 
work, and my stuff.  We have an HP 5340A with a 10811 inside. It must 
have been upgraded at some point in the past, the display uses Nixie 
tubes.  I calibrated it c2000 using a HP Cs standard. That lab and it's 
equipment are gone.  :-(


From ebay / China I got a simple GPSDO that uses a Trimble 57963 
inside.  I use the output of the 10811 in the 5340A to drive an HP 
53131A.  I then measured the 10 MHz output of the GPSDO using the HP 
53131A and got 10,000,000.08 Hz.


Assuming the GPSDO is correct, is 0.08 Hz drift over 20 years a 
reasonable amount of drift for an 10811?


I have an HP Z3801A, once I get a power supply for it I can check the 
other GPSDO.


Thanks

Robert
KA3ZYX

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Re: [time-nuts] Trimble 57963

2019-12-12 Thread Robert DiRosario


Roger,

Thanks for the information.  That explains the lack of information on 
the web.


Robert


On 12/10/2019 07:38 PM, Roger Tilsley wrote:

Greetings Robert,

I have one of these and it works very well running on 6 V.  I have been warned 
off low operating voltage OCXOs by an OCXO manufacturer.  This manufacturer 
would not countenance manufacturing OCXOs operating on 5 V.  There is little 
technical information available,  I tried Trimble for info and was told that it 
was designed for a specific customer and that all the information was customer 
confidential - if I had paid a contractor a substantial sum to produce a 
specific design for me, I would not be happy if the manufacturer sent technical 
details to anyone who enquired!  I can therefore understand the policy and it 
does explain the shortage of technical information.

Regards,
Roger T.

On Tue, 10 Dec 2019 09:43:23 -0500, Robert DiRosario  wrote:


I just received an Trimble 57963-D GPSDO with a Trimble 73090 OCXO.

There is very little information about this on the web.  What voltage
does this run on?

Some information I found online says 6 volts.  The seller says 5.5V.  I
got it from ebay / China.

I did get a breakout board and the 50 pin cable. \

Thanks
Robert


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[time-nuts] Trimble 57963

2019-12-10 Thread Robert DiRosario


I just received an Trimble 57963-D GPSDO with a Trimble 73090 OCXO.

There is very little information about this on the web.  What voltage 
does this run on?


Some information I found online says 6 volts.  The seller says 5.5V.  I 
got it from ebay / China.


I did get a breakout board and the 50 pin cable. \

Thanks
Robert


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[time-nuts] HP 105 option C89

2019-12-07 Thread Robert DiRosario


What is HP option C89 on an HP 105B?

Thanks

Robert


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[time-nuts] TrueTime XL-DC questions

2019-11-15 Thread Robert DiRosario

At a hamfest a few of weeks ago I got a TrueTime XL-DC, with antenna and
feedline for $45. :-) With the antenna setup in my living room it works
great, in good weather. It's the 1U version, with only the center LCD
display. The IRIG-B output works. I found a manual at

https://web.archive.org/web/2016111531/glacier.lbl.gov/gtp/DOM/Support/xl-dc-manual.pdf.
There is also on at
https://web.archive.org/web/20161226212915/https://ics-web.sns.ornl.gov/timing/151-652-893man.pdf,
but it's newer than my unit. The manual shows the unit labeled as
Symmetricom. with a large LCD for the time/date only and the small LCD.
Mine is labeled TrueTime and has only the small LCD. The manuals do not
have any information on the option cards. Is that documentation on the
web anywhere?

I have two option cards. One is an NTP card, labeled NTL-XL 87-6003-XL,
with an AUE Ethernet port.

The second card is labeled “HAVE QUICK II” 86-396-3 and has one of three
BNC connectors installed. A scope shows that it puts out a low speed
serial digital signal. Does anyone know what this card is for? The US
military has a secure radio system named Have Quick, everything Google
turns up is for that.

Can I upgrade this unit with one of these cards, to get 10 MHz output?

https://www.ebay.com/itm/Used-Truetime-XL-DC-GPS-Time-Frequency-Receiver-Module-Card-85-600-Rev-C/312792439289

It's made to go into the larger 2U version. If I remove the top bracket
it will fit in my unit, but will it work?

Is the 10 MHz output a GPSDO?

On my unit Function 71 shows on the LCD display:

Osc Phase, I see numbers +/- in the range of e-9 to e-10. It updates at 2 Hz

Osc Offset, same as above but the scale is +/- e-10 to e-11, sometimes
down to e-14. It also updates at 2 Hz

Osc Drift is of the order of 10e-9 per day. It updates at 2 Hz, or slower.

DAC is -17645, +/- 30 or so, and it doesn't update/change very often.

Respone Time 1.250E+01 seconds. It does not change, and the maual makes
to mention of it.

Manual:

"Oscillator phase" is the instantaneous error between the XL-DC timing
outputs and GPS.

"Oscillator offset" is the frequency offset or error with respect to the
GPS frequency

"Oscillator drift" is the change in oscillator frequency per day.

"Oscillator DAC" is the signed 16 bit DAC control integer which sets the
DAC output voltage to control

the internal or external oscillator.

On this list the next question is, how good is this? Looking at the
manual and inside of the unit I think

it has just a TCXO.

I will use the 1 PPS output to drive a Shera board.

Thanks

Robert

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[time-nuts] Re: HP105B

[time-nuts] Raspberry Pi with TimeHat thinks it's 2002!

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[time-nuts] Re: TimeHat

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[time-nuts] ThunderBolt question

Re: [time-nuts] GPS antenna splitter recommendation?

Re: [time-nuts] Vaperware Parts and pulse stretching circuits

Re: [time-nuts] Connector options for HP10811A?

Re: [time-nuts] Connector options for HP10811A?

Re: [time-nuts] Synchronisation of crystal oscillators

Re: [time-nuts] HP 5335A and using the HPIB for control

Re: [time-nuts] Frequency standards for different tau in Allen Dev measurement

Re: [time-nuts] 10811 performance

Re: [time-nuts] 10811 performance

[time-nuts] 10811 performance

Re: [time-nuts] Trimble 57963

[time-nuts] Trimble 57963

[time-nuts] HP 105 option C89

[time-nuts] TrueTime XL-DC questions

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