Re: [time-nuts] TAPR "PulsePuppy" Pot Selection

[Brian, WA1ZMS]

I have seen similar issues to Dana's and have told myself it must be torque 
left in the gear-train within the pot. Maybe all in my mind as well, but it 
seems real to me on some equipment.

-Brian, WA1ZMS

> On Dec 24, 2017, at 5:26 PM, Dana Whitlow <k8yumdoo...@gmail.com> wrote:
> 
> I think I need to clarify what I mean by "backlash".  It is not simple free
> play in
> the adjustment mechanism- it is something much more irritating, as follows:
> 
> I sneak up on the desired result, but manage to overshoot slightly.  So I
> back
> off on the screw, and find that at first the result continues to change in
> the
> *original* direction (making the overshoot even worse) for a bit before
> finally
> reversing as I wanted it to.  This behavior is not conducive to having a
> good
> time making critical adjustments, nor does it lend any confidence in the
> stability
> of the adjustment in the face of handling.
> 
> Dana
> 
> 
> On Sun, Dec 24, 2017 at 4:06 PM, Charles Steinmetz <csteinm...@yandex.com>
> wrote:
> 
>> John wrote:
>> 
>> I didn't really notice much backlash, though when setting oscillators I
>>> try to approach (slowly) from one direction until it's "good enough" and
>>> then stop, to avoid that problem.
>>> 
>> 
>> The hot tip is not to just "sneak[] up on the sweet spot and then walk[]
>> away," as Dana put it.
>> 
>> Anytime you have an adjustment with some hysteresis (classic example is
>> setting a d'Arsonville movement to zero), you want to sneak up to the
>> perfect setting and then run the adjuster *back* the way you came just a
>> touch, to leave the adjusted part on its own without any mechanical
>> connection to the adjustor mechanism.  Such contact is almost always the
>> culprit if the adjustment drifts after you set it.
>> 
>> This takes some "feel" for the motion of the adjuster mechanism, but it is

___
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.

[time-nuts] Why 80MHz?

[Brian, WA1ZMS]

I have noticed, of late, several used 80MHz OCXOs for sale.  Is there a 
particular industry that uses 80MHz as a typical reference freq?

I'm sure there's a reason why it is 80 vs. 100 or 10 or 5..  I just don't 
know what it is.

-Brian
___
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.

Re: [time-nuts] WWV 25 MHz antenna switched to circular polarization

[Brian, WA1ZMS]

FWIW.We're at an 11 yr low for solar activity. Thus no big suprise that 
25MHz is not covering the US very well, but a rare opening is always possible.

-Brian
> On Jul 16, 2017, at 7:32 PM, paul swed  wrote:
> 
> Not hearing wwv on 25 MHz but 15 is fine. Using a beam and r1051 receiver.
> Maybe its not on for the weekend. Its a 2 KW signal so should be able to
> hear something.
> Regards
> Paul
> WB8TSL
> 
>> On Fri, Jul 14, 2017 at 9:29 PM, paul swed  wrote:
>> 
>> Sorry its a bit lower in the site that they resumed broadcasting.
>> I thought it had been off for many years. Amazing that they kept the
>> transmitter in shape for operation.
>> Regards
>> Paul
>> WB8TSL
>> 
>>> On Fri, Jul 14, 2017 at 9:27 PM, paul swed  wrote:
>>> 
>>> I went to the wwv site and do not see 25 MHz mentioned. I do see 20 MHz.
>>> 
 On Fri, Jul 14, 2017 at 1:17 PM, paul swed  wrote:
 
 Gregory,
 I have to be honest and say I didn't even think wwv was on 25 MHz
 anymore.
 Son of a gun. I will have to listen.
 Paul
 WB8TSL
 
> On Fri, Jul 14, 2017 at 1:14 PM, Gregory Beat  wrote:
> 
> As reported by ARRL, a few days ago, on July 7th the 25 MHz antenna for
> WWV was changed to circular polarization.
> http://www.arrl.org/news/wwv-25-mhz-signal-swapped-to-circul
> ar-polarization
> 
> Matt Deutch, N0RGT the Lead electrical engineer at WWV said it’s hoped
> that the latest antenna change to circular polarization might be helpful 
> to
> anyone studying radio propagation (ionosphere) during next month’s total
> solar eclipse (August 21, 2017), which will be visible across the US.

___
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.

[time-nuts] WWV off-air for 2 days...

[Brian, WA1ZMS]

https://www.nist.gov/pml/time-and-frequency-division/time-services/wwv-broadcast-outages



-Brian, WA1ZMS
iPhone
___
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.

Re: [time-nuts] 5061A Beam Current went high

[Brian, WA1ZMS]

I know this sounds "insane", but could the unit have been on the wrong Cs peak 
for some time now?


-Brian, WA1ZMS
iPhone

> On Aug 22, 2016, at 3:02 PM, Pete Lancashire <p...@petelancashire.com> wrote:
> 
> I fired up my old 5061A about 3-4 times a year to keep the tube pumped
> down. I usually run it for 1 to 2 hours to keep it pumped down.
> 
> 
> This time was different,
> 
> 
> My GPSs have been off the air from getting a new roof and not being in any
> rush to get the antennas back up, etc.
> 
> 
> So ... I wanted to calibrate a couple devices for a friend and fired up the
> 5061A, got it locked "Green Light" and gave him a call.
> 
> 
> Up until now, beam current for me has been about 8-10 when peaked. The
> number recorded on the door is 19.
> 
> 
> He got delayed, and showed up about 8 hours later. We went to the lab, and
> the green light was still on, BUT the beam current was around 30.
> Everything else was where it was normally which is pretty much was was
> recorded on the door long ago.
> 
> 
> Any ideas of what I should look for first, before starting from the power
> supplies and checking everything ?
> 
> 
> -pete
> ___
> 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.
___
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.

Re: [time-nuts] FS: Distribution amps

[Brian, WA1ZMS]

The FS710 has been sold.

-Brian, WA1ZMS
iPhone

> On Sep 27, 2015, at 2:19 PM, "Brian, WA1ZMS" <wa1...@att.net> wrote:
> 
> Hi all-
> 
> Time to clean out some extra items.
> 
> I have one SRS FS710. Tested & works. Time-nuts price $150 + shipping to US
> address.
> I have two HP5087A dist. amps. Each one optioned a bit different. Tested &
> work. $75/each + shipping to US address.
> Also have one Austron 2100F. Make offer!
> 
> Contact *off-list* if interested.
> 
> Thanks,
> -Brian, WA1ZMS
> 
> 
> ___
> 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.
___
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.

Re: [time-nuts] FS: Distribution amps

[Brian, WA1ZMS]

Both HP5087's have been sold.

-Brian, WA1ZMS
iPhone

> On Sep 27, 2015, at 2:19 PM, "Brian, WA1ZMS" <wa1...@att.net> wrote:
> 
> Hi all-
> 
> Time to clean out some extra items.
> 
> I have one SRS FS710. Tested & works. Time-nuts price $150 + shipping to US
> address.
> I have two HP5087A dist. amps. Each one optioned a bit different. Tested &
> work. $75/each + shipping to US address.
> Also have one Austron 2100F. Make offer!
> 
> Contact *off-list* if interested.
> 
> Thanks,
> -Brian, WA1ZMS
> 
> 
> ___
> 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.
___
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.

Re: [time-nuts] OCXO with ADEV of 1E-13 on Pluto Mission

[Brian, WA1ZMS]

The crystal in the ref osv. came from Bliley. The part number is BG-61.  I have 
no idea what the current cost is, but like most very good oscillators the 
crystals were hand sorted and graded.

-Brian, WA1ZMS
iPhone

 On Jul 16, 2015, at 11:17 AM, John Stuart j.w.stu...@comcast.net wrote:
 
 Here is an interesting link to the New Horizons Mission to Pluto radio
 system design.
 Note last section describes an OCXO with ADEV = 1E-13 at 1s, and aging rate
 of 1E-11 per day.
 
 http://www.uhf-satcom.com/amateurdsn/Paper-969.pdf 
 
 
 
 I wonder if their spares will show up on eBay? 
 
 
 
 John Stuart, KM6QX
 
 Lafayette, CA
 
 ___
 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.
___
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.

Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Article

[Brian, WA1ZMS]

Gentlemen-

I have my paper copy in front of me with the original article.
I am not certain that I can just scan it and send it around due to
ARRL  Author copyright matters.  But I am willing to scan it.

With all due respect to John, K6IQL the author who spent much time
on his design..I would opine that an equivalent doubler could be
made from the Wenzel doubler circuits that are on the Wenzel web
page and from first-hand experience...I used such a 5-to-10 MHz doubler
for all of my amateur radio projects up through 403GHz.

The K6IQL design, in brief, splits the 5MHz signal into two paths.
One passes to the LO port of a Double Balanced mixer, while the
second path goes through a 90-deg phase shift network and into the
RF port of that JMS-1MH mixer.  The output is taken from the IF
port. The output is then buffered  filtered. He spent much design effort
on the 90-deg phase shift network to keep it all temp stable.

Personally, I'm lazy and like the Wenzel full wave rectifier design with
a nice BPF on the output to obtain a clean 10MHz.

-Brian, WA1ZMS/4


-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Oz-in-DFW
Sent: Wednesday, November 12, 2014 4:41 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Quad Driven Mixer 5 to 10 MHz Doubler Atricle

Only a small subset of QEX articles on available in digital format. This isn't 
one of them. We'll either need to get a copy from the author, or from a QEX 
subscriber.

On 11/12/2014 2:34 PM, Dave M wrote:
 I am able to download the files associated with the article, but not 
 the article itself.  Guess I need to be a paying member to get the 
 article.  The only files in the download are the XLS file for 
 calculating the filter values, and the parts list.

 It's at http://www.arrl.org/qexfiles in the year 2011 listings, 
 filename 3x11_Roos.zip titled Converting a Vintage 5 MHz Frequency 
 Standard to 10 MHz with a Low Spurious Frequency Doubler

 Dave M

 John C. Roos via time-nuts wrote:
 Several list members contacted me expressing interest in the article. 
 None of them were able to download much or anything from the ARRL QEX 
 web site. That includes me and other ARRL members.
 I am working the issue with one call to ARRL so far today. I will 
 contact Larry Wolfgang at ARRL and see what Ican bust loose. So hang 
 in there. It is a cute technique, not originated by me, but useful. 
 Right now I have to get the ARRL FMT done first.
 -73 john c roos k6iql


 ___
 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.


--
mailto:o...@ozindfw.net
Oz
POB 93167
Southlake, TX 76092 (Near DFW Airport)



___
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.

___
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.

Re: [time-nuts] MH370 Doppler

[Brian, WA1ZMS]

I thought that Inmarsat terminals had AFC to the sat's down-link.  Not to the 
degree of true phase-lock like DSN has but enough so that the sat's abillity to 
do doppler correction on the uplink is valid to help with BER, etc... Otherwise 
the doppler correction would be of no help and not be needed.

-Brian, WA1ZMS/4
iPhone

 On Aug 18, 2014, at 12:53 PM, Joe Leikhim jleik...@leikhim.com wrote:
 
 Is anyone paying attention to all the chatter about the lost aircraft MH370, 
 Inmarsat's supposed flight tracks based on 6 or 7 pings (1 per hour), the 
 Doppler shift (BFO) and transaction timing (BTO) etc??
 
 Basically from my perspective they are putting too much stock into the 
 Doppler which relies in part upon the stability of the satellite terminal in 
 the 777 aircraft. My question is how stable an oscillator (reported OCXO - 
 not confirmed)  would be under the extremes of either or both a cabin fire or 
 decompression event. There is a website (Duncan Steel Blog) where some math 
 brains are trying to sort out the raw data provided by Inmarsat. They have 
 made assumptions about the stability of the local oscillator in the 
 satellite, but I think the aircraft satellite terminal's master oscillator is 
 a variable they have pushed aside.
 
 -- 
 Joe Leikhim
 
 
 Leikhim and Associates
 
 Communications Consultants
 
 Oviedo, Florida
 
 jleik...@leikhim.com
 
 407-982-0446
 
 WWW.LEIKHIM.COM
 
 ___
 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.
___
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.

[time-nuts] Cutler NAA on 24.0kHz....

[Brian, WA1ZMS]

So does anyone know what frequency stability NAA has as of today?

 

When I fire-up my VLF RX converter they are so loud I'd hate to live near
the site.

One might be able to hear it with silver fillings in their teeth while
eating a lemon! ;- )

 

 

-Brian, WA1ZMS

 

___
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.

Re: [time-nuts] OT Gel Cell question

[Brian, WA1ZMS]

At the risk of adding fuel to the fire, I'd like to chime in and then will
go quiet.

Based on my first-hand day-job experience:
The consumer UPS units I have seen seem to run the float-voltage on Gel
Cells
at the very high-end of the cell's spec.  The goal appears to be to get the
battery
back to full terminal voltage and do it fast. That way the next AC mains
drop out
can utilize the full capacity of the Gel Cells.  The long term downside is
that the
cell would rather float at about a volt less or so and thus the life of the
cells are
reduced rather sharply.  Great for the UPS vendors; they get to sell
replacement
cells!

If one enters the 10kW and up category the game changes and the UPS vendors
take
much care to use a multi-stage charger system to get bulk charge into the
cells, but
not to float or top off charge the cells too much.

Enter the modern AGM-I and AGM-II cells and it becomes a grey area that I am
not
well educated about.  I asked for hard data from the battery vendors, but
the answers
were mixed at best.

Blunt answer I see is:
Do not treat flooded lead acid the same as Gel nor as AGM-I nor AGM-II.
And ALWAYS use temp sensors for best performance!

My 2 cents in the RF/Telecom World.

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of paul swed
Sent: Monday, July 28, 2014 8:17 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] OT Gel Cell question

Elio
Oh man I have seen the amp hour magic also.
Thought maybe I was just getting older batteries. We have major home chains
in the US that batteries sit around for quite some time as measured by the
dust on them. So I was thinking that was the case.
Regards
Paul.



On Mon, Jul 28, 2014 at 6:50 PM, Elio Corbolante elio...@gmail.com wrote:

 In my previous work I was developing UPSs: I can confirm that in the 
 last years the quality of the typical gel batteries has declined.
 What once was 7Ah batteries now are sold as 9Ah ones!
 And 5-6Ah ones are sold as 7Ah... :(
 One of the best way to identify the quality of sealed batteries is 
 to weigh them: the heaviest have the highest capacity (and in general 
 are also the best because the producer didn't spare on materials).

 _   Elio Corbolante.
 ___
 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.

___
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.

___
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.

[time-nuts] Looking for a particular OCXO....

[Brian, WA1ZMS]

I am trying to repair my HP-8920 RF Com test set since its internal

10MHz OCXO has aged way beyond the DAC EFC cal range.  (There

is no trimmer cap to allow adjustment.)

 

The OCXO is 10MHz and is marked PTI XO1145.

PTI no longer lists nor seems to sell this OCXO.

 

Has anyone seen or have a replacement OCXO or already been

done this path before?  I hate to re-invent the wheel.

I can buy a used A15 ref module but I still may end up with one

that has an OCXO that's out of cal range.

 

Reply off-list is fine.

 

-Brian, WA1ZMS

 

___
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.

Re: [time-nuts] Looking for a particular OCXO....

[Brian, WA1ZMS]

My high-spec ULN Wenzels have trimmers.

This this thing is 16Hz high at 10MHz so it's way off.  Must be sudden failure. 
If I use an external ref the test set is fine. OK for lab use. But a pain when 
out working in the field on ham repeaters. It may be an OEM number.  At work we 
noticed quite a change in PTI product lines after MTron bought them.

-Brian, WA1ZMS/4
iPhone

 On May 26, 2014, at 5:15 PM, Bob Camp kb...@n1k.org wrote:
 
 Hi
 
 On May 26, 2014, at 4:31 PM, Brian, WA1ZMS wa1...@att.net wrote:
 
 I am trying to repair my HP-8920 RF Com test set since its internal
 
 10MHz OCXO has aged way beyond the DAC EFC cal range.
 
 How far out is it?
 
 (There
 
 is no trimmer cap to allow adjustment.)
 
 Trimmer caps went out a long time ago on OCXO's
 
 
 
 The OCXO is 10MHz and is marked PTI XO1145.
 
 It’s probably an OEM part number
 
 PTI no longer lists nor seems to sell this OCXO.
 
 They likely only sold that part to HP
 
 
 
 
 Has anyone seen or have a replacement OCXO or already been
 
 done this path before?  I hate to re-invent the wheel.
 
 I can buy a used A15 ref module but I still may end up with one
 
 that has an OCXO that's out of cal range.
 
 
 
 Reply off-list is fine.
 
 
 
 -Brian, WA1ZMS
 
 
 
 ___
 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.
 
 Bob
 
 
 ___
 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.
___
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.

Re: [time-nuts] Looking for a particular OCXO....

[Brian, WA1ZMS]

Boy you are spot on about what damage sales guys can do.

The original OCXO spec is x10 better than the 16Hz I get with the DAC at the 
limit.

Thanks.

-Brian, WA1ZMS/4
iPhone

 On May 26, 2014, at 6:25 PM, Bob Camp kb...@n1k.org wrote:
 
 Hi
 
 
 On May 26, 2014, at 5:54 PM, Brian, WA1ZMS wa1...@att.net wrote:
 
 My high-spec ULN Wenzels have trimmers.
 
 
 I doubt that HP has put a trimmer OCOX  into a new design since the 10811 was 
 new. The Wentzel ULN’s are *not* high volume parts.
 
 This this thing is 16Hz high at 10MHz so it's way off.
 
 16 Hz is 1.6 ppm. That’s not really all that far. If the oven failed it would 
 be much farther off
 
 Must be sudden failure. If I use an external ref the test set is fine. OK 
 for lab use. But a pain when out working in the field on ham repeaters. It 
 may be an OEM number.  At work we noticed quite a change in PTI product 
 lines after MTron bought them.
 
 Renumbering all the products is what keeps the marketing guys employed…
 
 
 -Brian, WA1ZMS/4
 iPhone
 
 On May 26, 2014, at 5:15 PM, Bob Camp kb...@n1k.org wrote:
 
 Hi
 
 On May 26, 2014, at 4:31 PM, Brian, WA1ZMS wa1...@att.net wrote:
 
 I am trying to repair my HP-8920 RF Com test set since its internal
 
 10MHz OCXO has aged way beyond the DAC EFC cal range.
 
 How far out is it?
 
 (There
 
 is no trimmer cap to allow adjustment.)
 
 Trimmer caps went out a long time ago on OCXO's
 
 
 
 The OCXO is 10MHz and is marked PTI XO1145.
 
 It’s probably an OEM part number
 
 PTI no longer lists nor seems to sell this OCXO.
 
 They likely only sold that part to HP
 
 
 
 
 Has anyone seen or have a replacement OCXO or already been
 
 done this path before?  I hate to re-invent the wheel.
 
 I can buy a used A15 ref module but I still may end up with one
 
 that has an OCXO that's out of cal range.
 
 
 
 Reply off-list is fine.
 
 which takes all the fun out of it 
 
 
 
 
 -Brian, WA1ZMS
 
 
 
 ___
 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.
 
 Bob
 
 
 ___
 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.
 ___
 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.
 
 Bob
 
 ___
 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.
___
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.

[time-nuts] testing thanks to Yahoo....please ignore.

[wa1zms]

-Brian, WA1ZMS

 

 

___
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.

[time-nuts] TEST 123... please ignore.....

[Brian, WA1ZMS]

 

 

-Brian, WA1ZMS/4

 

___
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.

[time-nuts] maybe OT: GLONASS

[Brian, WA1ZMS]

I do not have a GLONASS receiver running at home at

this time, but the media reported a total GLONASS

outage a day or so ago.  Was it real or just rumor?

 

A co-worker in the lab at my day-job says he thinks

he caught a GLONASS RX acting badly.

 

Just technical curiosity. 

Sorry for BW.

 

-Brian, WA1ZMS/4

 

___
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.

[time-nuts] Interesting video....well done....

[Brian, WA1ZMS]

I found this to be a nice video for the non-Time Nut to try and understand
what  why about time..

 

http://knowmore.washingtonpost.com/2014/03/17/this-man-knows-what-time-it-is
-but-not-what-time-is/

 

 

-Brian, WA1ZMS/4

 

 

___
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.

Re: [time-nuts] New WWVB modulation format receivers (NOT)

[Brian, WA1ZMS]

500GHz? You must mean 50GHz.
Because 1Hz at 500GHz is 2E-12.  (You're already there at your goal.)  And
what frequency counter are you using at half a THz? :- )

(My highest freq 2-way ham contact has been on 403GHz and that took me years
to make.)

-Brian, WA1ZMS/4


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Albert
Sent: Friday, February 21, 2014 1:41 PM
To: Chris Albertson; Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] New WWVB modulation format receivers (NOT)

Well if we are talking about $50 then you have my attention.


No I am not afraid to use a soldering iron.  Amateur radio is not my main
interest here.  I have the same compulsion many of you out there seem to
have, that if I can get more accuracy I want it.  I get that content smile
on my face when my counter reads a string of zeroes on a measurement that is
supposed to do just that.

I am doing a lot better than 1 ppm right now.  I have my counter and signal
generator agreeing within about 1 Hz at over 500 GHz.  When I get one beat
in 10 seconds against 20 MHz WWV I have 5 ppb I think.  I am close to that
but it gets sticky using 20 MHz to communicate, plus the signal is only
available in my location for a few hours on most days.

I am doing similar things with voltage but you can't communicate voltage
over the radio so I don't have that kind of agreement, more like 50 ppm.

It's all in fun; I have no legitimate need for this accuracy.

Bob


___
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.

Re: [time-nuts] The pendulum problem...

[Brian, WA1ZMS]

Mike-

Yes, I was wrong. The idea of constant driving power was around. Sadly most of 
these early American tall clocks with often sand filled weights used a simple 
design since as you noted cost was important and raw metals such as brass was 
hard to produce locally and often imported from Europe.

I think the best I can do is to use the basic design from the article that 
David noted and will have to adjust the clock once a week after winding.

-Brian, WA1ZMS/4
iPhone

On Jan 31, 2014, at 4:33 AM, mike cook michael.c...@sfr.fr wrote:

 
 Le 31 janv. 2014 à 06:06, Brian, WA1ZMS a écrit :
  snip
 
 Modern pendulum clocks have a modified gear drive where the
 
 escapement is still being driven while the main wheel is being advanced
 
 to wind the weight cable. Not the case for 200+ year old clocks.
 
 
 
 It is not so much the case that it wasn't available as not always implemented 
 . The problem, and its solution maintaining power  had been addressed by 
 many since Christian Huygens in the 17th C. and also John Harrison , the 
 inventor if the marine chronometer in the mid 18th C.  Similarly the 
 principle exists for spring wound clocks, but is often omitted to keep the 
 price down. 
 
 
 Regards,
 
 -Brian, WA1ZMS/4
 
 
 
 
 
 ___
 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.
___
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.

Re: [time-nuts] The pendulum problem...

[Brian, WA1ZMS]

Thanks for all the ideas and replies.  Let me see if I can address all
points in just
one e-mail.

1) The clock(s) in question are very costly and to modify them in any way
would
instantly kill the value. These are part of history collection in 100%
original condition.

2) These clocks wind with a crank handle and winding rolls the cable back
onto the
main-wheel drum.  (Chain drive clocks were a ~100 year later design in
America)

3) The pendulum is 1 meter long and takes a full second to travel from one
end to the
other. So 1PPS or 0.5PPS synching is easy to do with a magnet, etc...

4) The escapement is of the anchor type, and as such when you wind the
running weight
you are driving the main wheel backwards. Such an escapement will run
backwards during
the winding and so I lose about 20 seconds or so during the winding.  The
speed of the wind
also can allow for a typical forward second to happen between the clicks on
the drum.
Sometimes I get a loss of 15 seconds, sometimes 20, etc...

5) The pendulum is still swinging during the wind. It's a 1kg weight on a 1m
rod. Takes
lots of energy to stop it.

6) The escapement shaft comes through the front dial to a small second hand
and so you
can see the second hand either pause, run forward, run backwards during a
wind.

I am concluding that without a fancy way to wind such a clock, it will only
be locked to
an external source during a typical 7-day run.  I'm asking for a solution to
a problem that
exists only as a want, not a need. Nevertheless, it is still very satisfying
to hear the tick
of such an old clock as the trigger LEDs on a 5370B blink at the same rate.
It was TVB that
pointed out to me the idea of just how many of our Rb's, Cs's, and OCXOs
will still be
running 200 years from now.  That thought still gives me pause.


-Brian, WA1ZMS

___
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.

Re: [time-nuts] The pendulum problem...

[Brian, WA1ZMS]

Joe-

You might be on to a good idea. If I could use a pair of optical sensors to 
watch the escapement wheel when winding, then I could count any movement in 
either direction or no movement at all and know how much to slew the timing 
pulses say over the next hour or two to get the clock back on time.

The nice thing is I can clip the opto sensors and remove them just as quickly 
with no change to the mechanism itself.

Again...what a great bunch the Time Nut crowd is!


-Brian, WA1ZMS/4
iPhone

On Jan 31, 2014, at 4:00 PM, Joe Leikhim jleik...@leikhim.com wrote:

 Count the period where the counterweight is disconnected from the movement 
 using a microswitch and then program the controller to speed up the clock to 
 make up the difference until the next time the clock needs to be rewound.
 
 Sort of like the way my bank just recalculated my escrow fund:-)
 
 -- 
 Joe Leikhim
 
 
 Leikhim and Associates
 
 Communications Consultants
 
 Oviedo, Florida
 
 jleik...@leikhim.com
 
 407-982-0446
 
 WWW.LEIKHIM.COM
 
 ___
 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.
___
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.

Re: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)

[Brian, WA1ZMS]

Tom-

A friend of mine John Delaney, of Delaney Antique Clocks (who has sold me some 
VERY nice 210+ yr old tall clocks made in my home town in Vermont) was there 
and told me he was impressed with your talk and that he now closed the loop 
with the idea of the Time Nuts which I told him I was involved with at the 
other-end of time keeping.

So for me.it's $20k for an extra Cs or the same for a clock that's over 200 
years old that was made where I call home.

I still need to synch an old clock to GPS, but have yet to work out the issue 
when I wind the clock once a week it takes load off the weight and the clock 
loses time. Yet another problem to solve.

-Brian, WA1ZMS/4
iPhone

On Jan 30, 2014, at 7:04 PM, Tom Van Baak t...@leapsecond.com wrote:

 I remember they recorded it. I just found out today it's on YouTube! Cool. I 
 guess. It's always weird to hear or see oneself speak, but if you watch it I 
 think it describes the time nut hobby pretty well.
 
 If you want to follow the PowerPoint presentation instead of the long talk, a 
 copy if it is here:
 
 http://leapsecond.com/dcc2013/
 
 /tvb
 
 - Original Message - 
 From: Bob Stewart b...@evoria.net
 To: Discussion of precise time and frequency measurement 
 time-nuts@febo.com
 Sent: Thursday, January 30, 2014 11:11 AM
 Subject: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)
 
 
 Today's SouthGateARC.org page has a link to Tom's talk at the 2013 TAPR/ARRL 
 Digital Communications Conference. I don't know whether this has been linked 
 to time nuts in the past, but it's an enjoyable presentation.
 
 southgatearc.org/news/2014/january/adventures_of_a%20_time_nut.htm#.UuqiQ5Uiwag
 
 Bob - AE6RV
 
 
 ___
 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.
___
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.

Re: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)

[Brian, WA1ZMS]

Oppps!
Thought I deleted the reflector e-mail!

Sorry for BW.
I am blushing.  :- (


-Brian, WA1ZMS/4
iPhone

On Jan 30, 2014, at 7:16 PM, Brian, WA1ZMS wa1...@att.net wrote:

 Tom-
 
 A friend of mine John Delaney, of Delaney Antique Clocks (who has sold me 
 some VERY nice 210+ yr old tall clocks made in my home town in Vermont) was 
 there and told me he was impressed with your talk and that he now closed the 
 loop with the idea of the Time Nuts which I told him I was involved with at 
 the other-end of time keeping.
 
 So for me.it's $20k for an extra Cs or the same for a clock that's over 
 200 years old that was made where I call home.
 
 I still need to synch an old clock to GPS, but have yet to work out the issue 
 when I wind the clock once a week it takes load off the weight and the clock 
 loses time. Yet another problem to solve.
 
 -Brian, WA1ZMS/4
 iPhone
 
 On Jan 30, 2014, at 7:04 PM, Tom Van Baak t...@leapsecond.com wrote:
 
 I remember they recorded it. I just found out today it's on YouTube! Cool. I 
 guess. It's always weird to hear or see oneself speak, but if you watch it I 
 think it describes the time nut hobby pretty well.
 
 If you want to follow the PowerPoint presentation instead of the long talk, 
 a copy if it is here:
 
 http://leapsecond.com/dcc2013/
 
 /tvb
 
 - Original Message - 
 From: Bob Stewart b...@evoria.net
 To: Discussion of precise time and frequency measurement 
 time-nuts@febo.com
 Sent: Thursday, January 30, 2014 11:11 AM
 Subject: [time-nuts] Tom's Adventures of a Time Nut (Banquet Talk)
 
 
 Today's SouthGateARC.org page has a link to Tom's talk at the 2013 TAPR/ARRL 
 Digital Communications Conference. I don't know whether this has been linked 
 to time nuts in the past, but it's an enjoyable presentation.
 
 southgatearc.org/news/2014/january/adventures_of_a%20_time_nut.htm#.UuqiQ5Uiwag
 
 Bob - AE6RV
 
 
 ___
 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.
 ___
 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.
___
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.

[time-nuts] The pendulum problem...

[Brian, WA1ZMS]

Now that I have exposed myself as being an antique time-nut as well

as a modern one, (I'm a man of extremes!) I have a question to the group..

 

Has anyone addressed the issue of trying to keep a pendulum clock

locked to an external reference (i.e.: via electro-magnet, etc.) and yet

can work around the problem that very old pendulum clocks have

an issue with the escapement drive stopping while such a typical 8-day

antique clock is being wound?

 

I can understand and deal with syncing the pendulum to an external

reference.. but you end up with a time offset when the clock's main

wheel is being wound once a week.  The pendulum does keep swinging

however the drive power to the 2nd gear is being removed while the

clock is being wound.

 

Modern pendulum clocks have a modified gear drive where the

escapement is still being driven while the main wheel is being advanced

to wind the weight cable. Not the case for 200+ year old clocks.

 

Regards,

-Brian, WA1ZMS/4

 

 

___
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.

[time-nuts] FS: HP-10811 variant....

[Brian, WA1ZMS]

I need to clean the ham-shack here...

I have one of these HP-10811 variants that I posted about last week that I'm
willing to part with.

It is marked HP-05071-60219.   It is a single oven version. It has been
tested and works .

 

Make me an offer above $60 and it is yours plus shipping. (USPS is best for
domestic sale)

Is it worth $60??? Based on e-pay prices that are all over the place, I
think it's a valid first try.

 

Please reply off-list.  First one wins.

Thanks for the BW.

 

Regards,

-Brian, WA1ZMS/4

Forest, VA

 

 

___
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.

[time-nuts] Interesting HP oscillators...

[Brian, WA1ZMS]

I have happened upon a pair of working HP 10811-like oscillators. They are
marked HP 0507-60219.  I do know they came from a special custom 1990's
attempt at a single oven version of the Z3801A.

 

Does anyone have any info or specs on such an OCXO?

 

They are surplus to my needs and they both test fine so unless they are
determined to be some kind of ultra-low PN oscillator, I could as well offer
them for sale to the Time-Nuts group.

 

Comments welcome.

 

Regards,

-Brian, WA1ZMS/4

 

 

___
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.

Re: [time-nuts] WAAS.....

[Brian, WA1ZMS]

In this case the timing rcvrs are located all with in a 20km radius with fixed 
known surveyed locations. The problem is GPS jamming that happens at random 
times. So one what if idea is to use a WAAS enabled rcvr and a yet to be 
selected parabolic antenna to point at a given WAAS sat. The concept is to give 
all rcvrs a single common view for critcal timing use in a comm system.

The ultimate goal is to try and reduce the number of times when full sky view 
GPS antennas are victims of GPS band interference.  This is only a half-baked 
idea of mine (in my day-job) but wanted Time Nuts feedback to see if it has any 
merit at all. BTW, the system has Rb for hold-over when there are problems but 
the frequent system error alarms indicating hold-over events is what I/we would 
like to reduce. New SNMP traps could mask off the events, but being an RF 
guy.I was thinking about a HW solution. :- )


-Brian, WA1ZMS/4
iPhone

On Jan 7, 2014, at 11:05 PM, Magnus Danielson mag...@rubidium.dyndns.org 
wrote:

 Brian,
 
 On 2014-01-08 02:25, Brian, WA1ZMS wrote:
 Hypothetical question
 For a given set of GPS timing grade receivers at multiple locations, is 
 there any advantage by limiting allowable SVN numbers to only be the WAAS 
 satellites?
 
 Well, if you do common view GPS comparision and is not into monitoring 
 observables separately (which is recommended), then there is some use for it, 
 as you configure the WAAS acceptance statically and only need to update it 
 once a new bird becomes available or one disappears. However, I wonder if 
 they are any good for that purpose anyway.
 
 So, in a more general way, I'd say no.
 
 More importantly, what are you trying to achieve?
 
 Cheers,
 Magnus
 ___
 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.
___
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.

Re: [time-nuts] WAAS.....

[Brian, WA1ZMS]

Hal-

Maybe *I* don't understand the WAAS data stream then.  In the case of a 
common-view single satellite timing transfer or calibration like is done 
every day by NIST, et al., could not a WAAS SVN be used for such an 
application? I short, my idea was to use just such a fixed common-view single 
WAAS SVN as the common source of 1PPS. Now if the WAAS data format does not 
fully replicate a classic GPS satellite, then yes my idea is all hog-wash.

As I said before, usual hold over during jamming events is working fine. But an 
idealy placed GPS antenna with full 360 degs of azimuth view only helps to hear 
more RF jamming sources in heavy urban environments. The result is our 
customers see log files that show sometimes  frequent (say once every 10 days) 
events where BOTH the active and hot standy by GPS timing receivers go into 
hold-over from jamming. 

My desire is to try and mitigate the appearence that our critical RF comm 
systems are of poor quality since there are these hold-over events taking place 
more often today than say 5 years ago.

We do not build the timing receivers, but we buy brand X. Switching to brand Y 
as a new vendor and getting them
qualified is painfull. Thus my original thought of trying a narrow beam width 
fixed antenna aimed at a WAAS satellite to reduce the effective antenna 
apperature and not hear the cars and trucks on the highways with their 
personal GPS jammers as they drive by  a classic GPS antenna.

Does that help explain it?
Or does WAAS not offer a classic 1PPS signal in it's data stream? I thought it 
had to in order to offer compatability.


-Brian, WA1ZMS/4
iPhone

On Jan 8, 2014, at 3:50 AM, Hal Murray hmur...@megapathdsl.net wrote:

 
 wa1...@att.net said:
 In this case the timing rcvrs are located all with in a 20km radius with
 fixed known surveyed locations. The problem is GPS jamming that happens at
 random times. So one what if idea is to use a WAAS enabled rcvr and a yet
 to be selected parabolic antenna to point at a given WAAS sat. The concept
 is to give all rcvrs a single common view for critcal timing use in a comm
 system. 
 
 Either you are trying to do something crazy or I don't understand what you 
 are trying to do.
 
 The WAAS satellites don't provide timing info.  They provide corrections to 
 the timing a receiver gets from normal GPS satellites.  So if all you can 
 hear is the WAAS satellites, you won't have any timing info to correct.
 
 How long does the jamming last and how close do your receivers have to track? 
 Can you use normal GPSDO hold-over mechanisms?
 
 
 
 -- 
 These are my opinions.  I hate spam.
 
 
 
 ___
 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.
___
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.

Re: [time-nuts] WAAS.....

[Brian, WA1ZMS]

Guys-

Thanks for the inputs and the mention of FEI and related patents. I thought the 
idea was not new but did not remember the details.

As for some answers:
As far as I have seen first-hand, the jamming is short in nature and events 
that I saw were from trucks on highways trying to defeat any tracking systems 
in the trucks.  An FCC enforcement issue here in the US resulted in one such 
user being made an example of by heavy fines since his truck was near a major 
airport where the FAA was trying to test GPS landing aids.

In my case, SW masking of hold-over alarms may be a shorter fix without any HW 
fixes. But that said, I wanted to be sure I understood the situation/mitigation 
at least well enough to talk about it with some info as back-up.

As for Hal's drop-out of GPS in the SFO area, that was a location that I had to 
address with a customer 18 months ago who was having chronic GPS drop-outs that 
I traced to GPS jamming and documented. Could be the same or not.

This latest issue is on the East Coast.

Again, there is a wealth of great knowledge here in Time Nuts and I'm glad to 
be able to call on help!

-Brian, WA1ZMS/4
iPhone

On Jan 8, 2014, at 11:57 AM, Björn b...@lysator.liu.se wrote:

 Hi Brian!
 
 Hmmm... should I finish the thread before commenting...
 
 The scenario has been discussed on the list before. There are publications 
 from Zyfer (fei) on Waas timing with a fixed dish antenna. There is also a 
 Fenton(Novatel) patent.
 
 --  
 
Björn
 
 div Originalmeddelande /divdivFrån: Brian, WA1ZMS 
 wa1...@att.net /divdivDatum:2014-01-08  09:25  (GMT+01:00) 
 /divdivTill: Discussion of precise time and frequency measurement 
 time-nuts@febo.com /divdivRubrik: Re: [time-nuts] WAAS. /divdiv
 /divIn this case the timing rcvrs are located all with in a 20km radius 
 with fixed known surveyed locations. The problem is GPS jamming that happens 
 at random times. So one what if idea is to use a WAAS enabled rcvr and a 
 yet to be selected parabolic antenna to point at a given WAAS sat. The 
 concept is to give all rcvrs a single common view for critcal timing use in a 
 comm system.
 
 The ultimate goal is to try and reduce the number of times when full sky view 
 GPS antennas are victims of GPS band interference.  This is only a half-baked 
 idea of mine (in my day-job) but wanted Time Nuts feedback to see if it has 
 any merit at all. BTW, the system has Rb for hold-over when there are 
 problems but the frequent system error alarms indicating hold-over events is 
 what I/we would like to reduce. New SNMP traps could mask off the events, but 
 being an RF guy.I was thinking about a HW solution. :- )
 
 
 -Brian, WA1ZMS/4
 iPhone
 
 On Jan 7, 2014, at 11:05 PM, Magnus Danielson mag...@rubidium.dyndns.org 
 wrote:
 
 Brian,
 
 On 2014-01-08 02:25, Brian, WA1ZMS wrote:
 Hypothetical question
 For a given set of GPS timing grade receivers at multiple locations, is 
 there any advantage by limiting allowable SVN numbers to only be the WAAS 
 satellites?
 
 Well, if you do common view GPS comparision and is not into monitoring 
 observables separately (which is recommended), then there is some use for 
 it, as you configure the WAAS acceptance statically and only need to update 
 it once a new bird becomes available or one disappears. However, I wonder if 
 they are any good for that purpose anyway.
 
 So, in a more general way, I'd say no.
 
 More importantly, what are you trying to achieve?
 
 Cheers,
 Magnus
 ___
 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.
 ___
 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.
 ___
 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.

___
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.

Re: [time-nuts] WAAS.....

[Brian, WA1ZMS]

We have a Rb for hold-over that is good for 72hrs per our needs. So we are fine 
in that regard.

That said, the vendor of the GPS box is a bit to fast and our equipment is also 
in some regards a bit too fast to report a string of alarms when both the main 
and hot-standby units go into hold-over.
We can manage that with the vendor and our own equipment alarm reporting.

The jamming events are fast and unpredictable given the ever-growing use of 
GPS jammers that anyone can find via a fly-by-night web page. The FCC is also 
staff limited to deal with fast and dynamic events. I am not sure that anybody 
can find a mobile and time dynamic jammer. One thing I did learn is that you 
will never find a truck with an active jammer at a sea port or transfer 
station. They WANT to be logged as being at those locations. Yet once on the 
road, jammer is often on so they can get cargo to destination ahead of 
schedule and get a pay bonus for doing a prompt job. Keep in mind that L1 
jammers are easy to obtain that make as much as 3W of RF power on the L1 freq. 
Please don't ask me how I know.

On this forum I cannot go into details due to nature of my day-job and our 
customers, but that said my original question has been answered by the FEI  
papers that claim that a WAAS directional antenna has some advantage.  As usual 
for me, I tried to re-invent the wheel.

CDMA or cellular timing is not a viable option if our systems need to be more 
robust than a cell phone network.

Sorry, I cannot go into our customer base.

-Brian, WA1ZMS/4
iPhone

On Jan 8, 2014, at 5:18 PM, Nathaniel Bezanson mys...@telcodata.us wrote:

 
 Brian, WA1ZMS  wrote:
 In my case, SW masking of hold-over alarms may be a shorter fix without any 
 HW fixes. 
 
 If you can mask short-duration alarms while still finding out about 
 persistent ones, then yes, that's probably the most pragmatic solution. 
 What's your holdover tolerance?
 
 Following from that, suppose a jammer parks nearby and doesn't leave in a 
 timely fashion. How long does it take for the FCC to swoop in (do they swoop? 
 in my mind they do) and find the source? Is that within your permissible 
 holdover window?
 
 But back to your original WAAS question, it sounds like it's time to haul out 
 the spare hardware and do some experiments! Even with the normal antenna, you 
 should be able to assess the validity of the configuration. Will the receiver 
 even let you specify just those few birds? It's almost a question of whether 
 they bothered to code an error message for such a stunt...
 
 (This next part may deserve its own thread. Please edit the subject-line if 
 replying to just this bit.)
 
 You might look into a CDMA-derived time source, long term. By working one 
 stratum away from GPS, you'll be listening to a plurality of pilots, each of 
 which is GPS-derived, and which are geographically diverse. A single GPS 
 jammer shouldn't knock out more than one tower at a time, and even if the 
 tower's local holdover OCXO isn't stellar and it begins to drift, your 
 CDMA-derived receiver is continually comparing and assessing the different 
 signals to discard the outliers. 
 
 Ideally, it's like having a bunch of diverse receive sites feeding back to 
 you on a jam-resistant (very strong) channel. Pessimistically, you've got no 
 visibility into the internal operation of those sites, and the only way to 
 infer their status is by comparing them against each other (or a local GPS 
 receiver, if you're not presently jammed yourself).
 
 As far as I can tell, the CDMA receivers are less explored than GPS, so you'd 
 be largely taking the manufacturer's word on a lot of things. 
 
 73 de NJ8Z
 ___
 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.
___
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.

[time-nuts] WAAS.....

[Brian, WA1ZMS]

Hypothetical question
For a given set of GPS timing grade receivers at multiple locations, is there 
any advantage by limiting allowable SVN numbers to only be the WAAS satellites? 
 

-Brian, WA1ZMS/4
iPhone

___
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.

Re: [time-nuts] Shortt Clock Recent Measurements

[Brian, WA1ZMS]

FWIW

Let me just second Tom's last comment:
Some of you readers might wonder why in this GPS age, two time nuts, each
with plenty of atomic clocks at home, would be talking about vintage
pendulum clocks. It turns out that pendulum clocks are still extremely
interesting timekeepers, from an experimental, scientific, and historical
perspective.

About 2 years ago the Time Nut in me became very interested in pendulum
clocks that were made in my home town in Vermont going back as far as 1797.
I now own several and a project is to take one of them that has a dead-beat
escapement (often noted for its better accuracy display of seconds with an
10 inch sweep hand in its day) into the 21st century with frequency locking
of the pendulum to the 1PPS from one of my GPS receivers.

AlsoAn antique clock dealer who is friend of mine was well pleased with
TVB's talk at a recent time conference on the West Coast.  So it is a mix of
old and new for me at this point.   Apologies if this goes OT.

Regards,
-Brian, WA1ZMS/4


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Tom Van Baak
Sent: Tuesday, December 10, 2013 5:48 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Shortt Clock Recent Measurements

 The Wiki page for the Shortt pendulum clock has a Recent Measurements
(1984)  paragraph that's in error.
 http://en.wikipedia.org/wiki/Shortt-Synchronome_clock#Recent_accuracy_
 measurement
 
 While it's probably true that the clock is stable to 200 uS per day 
 (i.e. 2E-9) I believe Alfred Loomis discovered the effect of the moon on
this clock a long time ago.

Hi Brooke,

The wiki page is correct. The heading is Recent Measurements and Pierre
Boucheron's 1984 effort certainly qualifies. Note the wiki doesn't claim
Boucheron was the first. In fact, even 30 years old, it is still the most
recent, and the only Shortt experiment for which we have raw data. See
http://leapsecond.com/pend/shortt/ for details.

One could try claiming that Loomis was the first to make detailed
measurements of a Shortt, but it would take some digging to prove he was
first and not just one of the first. I mean, if you look at the list of
who received the one hundred Shortt's that were manufactured, many
laboratories had more than one, not to mention the ones that William Shortt
himself owned at the factory. Certainly there was a lot of time measurement
going on in the 20's and 30's. It would take a lot of work to uncover what
was known by whom and when. Or who published first or not.

I think Loomis took it a wonderful extreme with his spark chronograph and
quartz oscillator via telephone time transfer setup. And that be bought
three clocks at once is classic and inspiring to any time nut! So I agree,
Loomis deserves mention on the Shortt wiki page.

Unrelated to gravity and tides, is the role that vacuum pendulum and
ovenized quartz clocks had in confirming that earth rotation was itself
irregular at the millisecond level. Credit for that usually goes to Scheibe
and Adelsberger in the late 30's, not Shortt or Loomis. And that of course
blends into the story of the leap second...

See my scan/OCR historical pendulum collection:
http://leapsecond.com/pend/pdf/ And my own precision pendulum-nut articles:
http://leapsecond.com/hsn2006/

Some of you readers might wonder why in this GPS age, two time nuts, each
with plenty of atomic clocks at home, would be talking about vintage
pendulum clocks. It turns out that pendulum clocks are still extremely
interesting timekeepers, from an experimental, scientific, and historical
perspective.

/tvb


___
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.

___
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.

Re: [time-nuts] GPS outage?

[Brian, WA1ZMS]

Guys-

Please forgive me for the BW..

My day-job mgmt. has also asked me today if I knew of any US regional GPS
issues, as we too have had several reports of
our customers systems going into Rb hold-over on or about the 4th of Sept.
Only fact I can find is that SVN 4 was noted as
an issue via: http://adn.agi.com/SatelliteOutageCalendar/SOFCalendar.aspx
But that can't be the root cause.

At work, I am now the go-to-guy for ANYTHING GPS related since I'm a
Time-Nut and we have customers who depend on
GPS timing for their  comm. systems;  and for reasons I cannot go into here
on this reflector.

So like Brad.I too have anecdotal reports of issues.  The sky is not
falling, nor was it a serious issue.
However if anyone has info that they cannot share via the reflector, a
private reply would be much appreciated.
I am not looking for info that cannot be openly shared. But if anyone has
hint or clue, I would much appreciate it.

BTWmy GPS receivers here in VA seemed to have had no issue. Go figure.

-Brian, WA1ZMS



-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Brad Dye
Sent: Wednesday, September 04, 2013 6:14 PM
To: Time Nuts
Subject: [time-nuts] GPS outage?

Readers of my newsletter are reporting a strange interruption of their GPS
reception yesterday -- mainly in the northeastern US but also in SC. This is
my first day on this mailing list -- for a while -- so I don't know if this
has been discussed or reported previously. Has anyone else noticed this? We
are trying to find out is there was some sort of system-wide issue or maybe
if it was local interference possibly caused by those GPS jammers that some
of the truckers have been using.

By the way, my newsletter is mostly about Paging, and we use GPS/DOs to keep
the paging transmitters (in simulcast mode) synchronized and on frequency.

Best regards,

Brad Dye, K9IQY
Editor, Wireless Messaging News
P.O. Box 266
Fairfield, IL  62837 USA
Telephone: 618-599-7869
Skype: braddye
http://www.braddye.com

___
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.

___
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.

Re: [time-nuts] GPS outage?

[Brian, WA1ZMS]

John-

I agree. We all should/would have seen
even a minor outage. That's what makes the event from early this week a rather 
odd event.

I have personally observed GPS jamming events from truck drivers trying to 
prevent being tracked. But those events are very localized it seems and are 
well bounded.

I cannot speak for others, but I am on
a presumption/ theory for our vendor supplied gear that the GPS engines may not 
have dealt very well with SVN 4 being tagged as not for use on
Sept 3  4.  Just a theory from an RF guy since I have no other explanation why 
some gear had issues yet 99% of us Time-Nuts never noticed an issue.

Oh well..

-Brian, WA1ZMS

On Sep 6, 2013, at 12:23 AM, John C. Westmoreland, P.E. 
j...@westmorelandengineering.com wrote:

 Hello All,
 
 Not to go off on a tangent here but are there 'time nuts' distributed
 around the globe in such a way as we'd know about an outage?
 
 One good hiccup by the Sun and it could cause an outage - correct?  (
 http://www.spaceweather.com)
 
 It wasn't so long ago we were told the Iridium 'Flares' were all that were
 left of Motorola's project and now you can go buy a phone here:
 http://iridium.com/default.aspx
 
 Regards,
 John W.
 
 
 
 
 
 
 On Thu, Sep 5, 2013 at 8:06 PM, Chris Albertson
 albertson.ch...@gmail.comwrote:
 
 Can anyone estimate how many GPS jammers there are in the New England
 area?   There just might be thousands.  I don't know.
 
 I think the reason most people are not effected is that most GPS user
 are mobile and if they are near a jammer it is only for a few minutes
 
 On Thu, Sep 5, 2013 at 4:59 PM, Bob Camp li...@rtty.us wrote:
 Hi
 
 You could indeed deploy a few thousand gizmos and have a pretty
 significant impact. I'm not at all sure that would be the easier task ….
 
 
 --
 
 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.
 
 ___
 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.
___
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.

Re: [time-nuts] 5MHz x 10MHz

[Brian, WA1ZMS]

My 2 cents

In a talking to Charles Wenzel about
this very topic some 13 yrs ago, I liked
it when he said sometimes it comes
down to the quartz-to-crud ratio of
the crystal that makes all the difference
for a given crystal frequency.

-Brian, WA1ZMS

On Aug 4, 2013, at 8:40 PM, Bob Camp li...@rtty.us wrote:

 Hi
 
 As with any real question, the answer is always that depends….
 
 Different offsets at different carrier frequencies will make you look at 
 different things….
 
 Bob
 
 On Aug 3, 2013, at 9:01 AM, Magnus Danielson mag...@rubidium.dyndns.org 
 wrote:
 
 On 08/03/2013 02:28 PM, Bob Camp wrote:
 Hi
 
 The whole drop frequency / better Q thing really only applies if you are 
 looking for ADEV with tau's  = 0.1 second.  If you are after phase noise, 
 then there are other things to worry about. 
 White noise and flicker noise of oscillator and buffer amps comes to
 mind. Naturally noise in the crystal itself.
 
 Cheers,
 Magnus
 ___
 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.
 
 ___
 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.
___
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.

Re: [time-nuts] 5MHz x 10MHz

[Brian, WA1ZMS]

He had no way to quantify the crud.  There are many
sources of it along the way.

His comments to me were aimed at the amount of contamination that
takes place during the plating of the electrodes on the quartz blank
itself as well as any crud that is left from the lapping of the blank.

His main point was that it make take trial and error testing of
say a dozen crystals to find the best of the lot for use in his ULN
oscillators.

My take is that 5MHz is not a fixed  magic number. Just a frequency that
works well for today's frequency standards and can be divided or multiplied
as needed.

As another post on this thread said, there are a number of factors involved
and while 1MHz might be better, the size of the crystal becomes a
trade-off.

What I don't know fills MANY text books!

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Hal Murray
Sent: Sunday, August 04, 2013 9:54 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5MHz x 10MHz


wa1...@att.net said:
 In a talking to Charles Wenzel about this very topic some 13 yrs ago, 
 I liked it when he said sometimes it comes down to the quartz-to-crud
ratio
 of the crystal that makes all the difference for a given crystal
frequency.

Neat.  Thanks.

How much crud is in a typical modern crystal?

How much was in natural quartz, say from WW II era?

I assume modern crystals are made from quartz grown in a lab using
techniques similar to what the semiconductor industry uses.  Are we talking
ppm or ppb?


Does anybody have any long term stability data on old crystals vs modern
crystals?  Yes, that's not very specific.  By old, I'm remembering the
crystals I saw as a kid (late 1950s).  It was just a few screws to open the
package.  I expect the ARRL handbook had recipes for adjusting the frequency
but my copy from those days is long gone.


--
These are my opinions.  I hate spam.



___
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.

___
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.

[time-nuts] [OT} audiophile outlets.....

[Brian, WA1ZMS]

What's gets me is that I didn't think of this snake oil first.
Had I thought of it first I could own a PTI H-MASER by now.   :- )

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Didier Juges
Sent: Tuesday, June 18, 2013 10:01 PM
To: n...@verizon.net; Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] HP and other equipment failure

audiophile outlets

You've got to be kidding but not even.

At least, nobody is forcing anybody to buy them...

Didier

Peter Gottlieb n...@verizon.net wrote:

The current distortion from simple transformer-rectifier-capacitor 
power supplies contains a lot of third harmonic content.  In a 3 phase 
system (as are all distribution systems for commercial and industrial) 
the third harmonic ADDS in the neutral, or creates circulating currents 
in a delta configuration.  These currents, as you mention, can get very 
large and were the cause of many

transformer explosions in cities as these power supplies became common.
 The
transformer designs had to be improved, but the PFC supplies make a big 
difference.

How many of you have looked at the power line waveform, especially in 
an industrial or commercial area?  Doesn't look much like a sine wave, 
does it?  So it's pretty funny to see audiophile outlets 
(http://www.dedicatedaudio.com/power_outlets).

Peter




On 6/15/2013 6:56 PM, stan, W1LE wrote:
 PFC to me is power factor correction, not only the classical power
factor to
 minimize (VAR) volt-amp reactive component,  but also to remove the 
 harmonic load  current imposd on the
electrical power
 system.
 A '90's onward technique. in th 80's and 90's without the harmonic
load
 current reduction and having
  a few 100 end items of equipment, each withtheir own  a switch mode
power
 supplly,
  it was not uncommon to find hundreds of amps of the third harmonc on
neutra,
   in the electrical power distribution system.

 Could be a serious EMC problem if you were dealing with voice grade
channels.
 And people safety issues.

 Stan, W1LE   Cape Cod



 On 15-Jun-13 5:52 PM, J. L. Trantham wrote:
 Sorry for the interruption but what is 'PFC'?

 Thanks.

 Joe

 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]
On
 Behalf Of Poul-Henning Kamp
 Sent: Saturday, June 15, 2013 4:09 PM
 To: Robert Atkinson; Discussion of precise time and frequency
measurement
 Cc: Perry Sandeen
 Subject: Re: [time-nuts] HP and other equipment failure

 In message
1371329221.83869.yahoomail...@web171902.mail.ir2.yahoo.com,
 Robert  Atkinson writes:

 While I agree with everything else you say, you CAN have too much 
 filter capacitance. At least where dc rectifier / filter
(smoothing)
 circuits are concerned. Increasing C causes increased ripple
current
 [...]
 And ripple current can be a major source of power-line frequency
noise in
 all electronics.

 The main reason why switchmode power-supplies today (can) outperform
linear
 power supplies with respect to noise, is because the legally
mandated PFC
 correction eliminates the bridge-rectifier ripple harmonics.

 I would not hessitate to use a good quality switchmode to replace
the linear
 supply in a HP5370B.

 I did some experiments a couple of years ago, with an
audio-amplifier:
 I put a standard PFC corrector chip on the secondary side of the
trafo.

 The overall result was not satisfactory, but the 50 Hz sneer
 we all know and hate was absent, and the Tzoing! power-on
mechanical
 shock from the trafo was also eliminated, as was the consequent
dimming of
 the lights ;-)

 The main reason not to do this, is that you need some physically
gargantuan
 coils for a 10A+ PFC-switcher.



 ___
 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.


 -
 No virus found in this message.
 Checked by AVG - www.avg.com
 Version: 10.0.1432 / Virus Database: 3199/5913 - Release Date:
06/15/13



___
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.

--
Sent from my Motorola Droid Razr 4G LTE wireless tracker while I do other
things.
___
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.

___
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.

Re: [time-nuts] 5071A Cs Oven

[Brian, WA1ZMS]

Paul-
Same here! :- )
The best way is to find a REALLY dead
tube and cut it open and see if the EM
first and second dynodes are clean, or
covered in a film of Cs. Short of heating
the dynode to vaporize off the Cs and
let the ion pump collect it, I think it
becomes a giant physics project.

One really crazy idea is to cut the steel
casing open, but leave the glass seal
intact. If that's even possible. Then.
you could use RF inductive heating like
what is used when you make a classic
vaccum tube, to heat the elements
inside and vaporize the occluded (sp?)
gases from the elements and let the
getter material or the ion pump gather
the crud up.

My only guess is if that was a real
practical way of adding life back to
a Cs tube, that HP or somebody would
have been doing it in the 1970's when
vaccum tubes were still in mass
production and the effort would have
paid off.

In light of the fact that Symetricom only
wants a paultry $18k for a new CBT...
and now with GPS birds running Rb's
rather than CsAND you can get a
CSAC for $1500 new, the demand for
Cs tubes has but a limited market.

Now if I could convince my XYL that
I must spend $250k on an H-MASER
then I'd be in Time-Nut's Nerdvana!

-Brian, WA1ZMS

On Oct 4, 2012, at 4:59 PM, paul swed paulsw...@gmail.com wrote:

 Brian
 Funny you mention the dirty emult. At the time I was wondering and if there
 was any insane way to get the Cs off the e multiplier. HV to ground or
 something to migrate them.
 Hold upside down and shake hard. ;-)
 Regards
 Paul
 
 On Thu, Oct 4, 2012 at 4:22 PM, Brian, WA1ZMS wa1...@att.net wrote:
 
 Rick can correct me on this...
 but my understanding is that it is
 almost never a case of running out
 of Cs from the oven, but that the
 dynodes of the electron multiplier
 become covered in used Cs and so
 the ultimate SNR and effective beam
 current falls to a point where there is
 no dependable beam current left to
 do much with.
 
 The tube that I sent to Paul, he was
 able to get some more current by
 running the Cs oven at a higher temp
 and as such is vaporizing off LOTS of
 Cs and can get a tiny bit of beam
 current to work with. But it is a down
 hill slide, since to keep the beam
 current up with a dirty E-mult, over
 time you need to keep running up the
 Cs oven temp to the point where you
 may just run out of Csor get an
 E-mult that is so covered with used
 Cs that there is no beam current to
 work with. You can always try and
 run up the E-mult voltage as well, but
 you then run the risk of arcing in the
 E-mult and an issue of burning up
 the resistor divider stack that I believe
 is part of the E-mult.
 
 I can see it now.. an end-of-life Cs
 tube that needs 35kV on the E-mult
 to get any beam current to work with!
 : -)
 
 
 -Brian, WA1ZMS
 
 On Oct 4, 2012, at 3:41 PM, paul swed paulsw...@gmail.com wrote:
 
 Rick
 Well I have the old 5060 and 61 tubes and indeed they run out O gas.
 I am using a 5060 tube in a 5061 and the Frankenstein works though it has
 only a few Cs. But heck it all locks after 48 hours.
 So someone said with humor lets buy some 5071 tubes for a couple hundred
 each.
 Guess I could have some fun getting that into the 5061. Suspect that
 would
 be the bride of Frankenstein then.
 Thanks for sharing the insights and experience.
 Paul
 WB8TSL
 
 On Thu, Oct 4, 2012 at 3:21 PM, Richard (Rick) Karlquist 
 rich...@karlquist.com wrote:
 
 These ideas are interesting.  AFAIK, there is very little
 chance of running out of Cs in many years, long past the
 time when something else in the tube will have reached its
 end of life.  Where did this idea come from?  Certainly, not
 anyone working at HP, Agilent or Symmetricom.  A LONG time
 ago, if you bought a high performance 5061, the increased
 Cs beam flow might have been an issue, but the amount of Cs
 shipped with the tube was increased before the 5071A
 such that running out of Cs is no longer an issue.
 
 If you turn off the Cs, you simply have a 10811 to connect
 to your GPS.  Except this 10811 has 10X the EFC range vs
 a stock 10811.  Again, this doesn't make a whole lot of sense,
 IMHO.
 
 BTW, another interesting idea is degaussing the CBT.  According
 to Len Cutler, this is completely unnecessary in the 5071A.  As
 anyone who knew Len can attest, if he thought something was
 good enough and didn't need to be improved, you could be
 sure about that.  For example, Len wanted us to use tantalum
 filter capacitors for energy storage in the power supply.
 Fortunately, we talked him out of that (actually the $100+
 cost helped to convince him).
 
 Due to customer demand (the customer is always right :-) the Santa
 Clara Division eventually released a degausser.  One of the reasons why
 this is not necessary in the 5071A is the Zeeman line measurement
 of the magnetic C field.  The 5061 was open loop.  So again there
 may have been a grain of truth behind the folklore.
 
 Rick Karlquist N6RK
 Member of the 5071A design team
 
 
 On 10

Re: [time-nuts] 5071A Cs Oven

[Brian, WA1ZMS]

Rick can correct me on this...
but my understanding is that it is
almost never a case of running out
of Cs from the oven, but that the
dynodes of the electron multiplier
become covered in used Cs and so
the ultimate SNR and effective beam
current falls to a point where there is
no dependable beam current left to
do much with.

The tube that I sent to Paul, he was
able to get some more current by
running the Cs oven at a higher temp
and as such is vaporizing off LOTS of
Cs and can get a tiny bit of beam
current to work with. But it is a down
hill slide, since to keep the beam
current up with a dirty E-mult, over
time you need to keep running up the
Cs oven temp to the point where you
may just run out of Csor get an
E-mult that is so covered with used
Cs that there is no beam current to
work with. You can always try and
run up the E-mult voltage as well, but
you then run the risk of arcing in the
E-mult and an issue of burning up
the resistor divider stack that I believe
is part of the E-mult.

I can see it now.. an end-of-life Cs
tube that needs 35kV on the E-mult
to get any beam current to work with! 
: -)


-Brian, WA1ZMS

On Oct 4, 2012, at 3:41 PM, paul swed paulsw...@gmail.com wrote:

 Rick
 Well I have the old 5060 and 61 tubes and indeed they run out O gas.
 I am using a 5060 tube in a 5061 and the Frankenstein works though it has
 only a few Cs. But heck it all locks after 48 hours.
 So someone said with humor lets buy some 5071 tubes for a couple hundred
 each.
 Guess I could have some fun getting that into the 5061. Suspect that would
 be the bride of Frankenstein then.
 Thanks for sharing the insights and experience.
 Paul
 WB8TSL
 
 On Thu, Oct 4, 2012 at 3:21 PM, Richard (Rick) Karlquist 
 rich...@karlquist.com wrote:
 
 These ideas are interesting.  AFAIK, there is very little
 chance of running out of Cs in many years, long past the
 time when something else in the tube will have reached its
 end of life.  Where did this idea come from?  Certainly, not
 anyone working at HP, Agilent or Symmetricom.  A LONG time
 ago, if you bought a high performance 5061, the increased
 Cs beam flow might have been an issue, but the amount of Cs
 shipped with the tube was increased before the 5071A
 such that running out of Cs is no longer an issue.
 
 If you turn off the Cs, you simply have a 10811 to connect
 to your GPS.  Except this 10811 has 10X the EFC range vs
 a stock 10811.  Again, this doesn't make a whole lot of sense,
 IMHO.
 
 BTW, another interesting idea is degaussing the CBT.  According
 to Len Cutler, this is completely unnecessary in the 5071A.  As
 anyone who knew Len can attest, if he thought something was
 good enough and didn't need to be improved, you could be
 sure about that.  For example, Len wanted us to use tantalum
 filter capacitors for energy storage in the power supply.
 Fortunately, we talked him out of that (actually the $100+
 cost helped to convince him).
 
 Due to customer demand (the customer is always right :-) the Santa
 Clara Division eventually released a degausser.  One of the reasons why
 this is not necessary in the 5071A is the Zeeman line measurement
 of the magnetic C field.  The 5061 was open loop.  So again there
 may have been a grain of truth behind the folklore.
 
 Rick Karlquist N6RK
 Member of the 5071A design team
 
 
 On 10/4/2012 9:45 AM, Tom Van Baak wrote:
 
 Bob,
 
 Right, not good. There should be a fault message associated with it.
 Check the internal log.
 
 OTOH, to conserve cesium, I've heard that some people run 5071A in
 standby mode most of the time and only turn on the cesium for a fraction of
 an hour a day or a week (to recal the quartz). Running in this standby mode
 is also advisable if one wants the best short-term performance out of a
 5071A, without the loop noise. In this respect it's just like a GPSDO - you
 get the best short-term performance if you turn off disciplining.
 
 /tvb
 
 Hi
 
 Is Cs oven: 0.0V a good thing on a 5071A?
 
 I suspect not, since either it or GPS is off frequency.
 
 Bob
 
 
 
 
 __**_
 time-nuts mailing list -- time-nuts@febo.com
 To unsubscribe, go to https://www.febo.com/cgi-bin/**
 mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 and follow the instructions there.
 
 
 
 __**_
 time-nuts mailing list -- time-nuts@febo.com
 To unsubscribe, go to https://www.febo.com/cgi-bin/**
 mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 and follow the instructions there.
 
 ___
 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.

___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts

Re: [time-nuts] GPS Jammer

[-Brian, WA1ZMS (iPad)]

One of fine units from Hong Kong delivered +32dBm of wide-band FM noise 
centered on 1575MHz!!!  Just a tad more range than 10m I would expect.

-Brian, WA1ZMS
(sent from my over-priced iPad3)

On Oct 3, 2012, at 8:44 AM, shali...@gmail.com wrote:

 It is not that hard to transmit broad band noise over the entire GPS channel 
 and clobber it entirely.
 
 Didier
 
 
 Sent from my Droid Razr 4G LTE wireless tracker.
 
 
 
 -Original Message-
 From: johncr...@aol.com
 To: time-nuts@febo.com
 Sent: Tue, 02 Oct 2012 9:33 PM
 Subject: Re: [time-nuts] GPS Jammer
 
 In considering the effect of a simple jammer on a GPS receiver, a 
 simple link analysis
 is insufficient.
 
 What must also be considered is the anti-jam capability of the receiver
 which due to spread spectrum processing gain will reject any simple
 jamming signal even though is it 10's of dB stronger than the desired 
 signal.
 
 73 -john k6iql
 
 ___
 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.
 ___
 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.

___
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.

Re: [time-nuts] GPS Jammer

[Brian, WA1ZMS]

Let me just say that that's flea power!
I saw some 80watt jammers being sold for movie theaters and churches.

There is some very black market items from China, via Hong Kong and can 
arrive at your doorstep in just 4 days via DHL! What's out there would scare 
you.

Been dealing with the fall out from such items in my day job.

-Brian

On Oct 2, 2012, at 4:43 PM, J. Forster j...@quikus.com wrote:

 Take a look at the specs of this unit:
 
 http://www.mobilephonejammer.com.au/covert-gps-jammer-portable-p-119.html
 
 The Power Output is 0.5 Watts and it claims a jamming range of 1-10 Meters.
 
 Anybody think there is something wrong?
 
 -John
 
 
 
 
 ___
 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.

___
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.

Re: [time-nuts] RFX GPSDO - Anybody played with one of these?

[-Brian, WA1ZMS (iPad)]

Shameless plug for JLT, but they helped me with a special application need in 
my day-job and it worked like a charm!

One happy customer.

-Brian, WA1ZMS
(sent from my over-priced iPad3)

On Oct 2, 2012, at 5:36 PM, saidj...@aol.com wrote:

 Hello Paul,
 
 thanks much for the feedback!
 
 Yes, we think we have identified a nice combination of oscillators, GPS,  
 and firmware that seems to work pretty well. The GPSTCXO units cannot be  
 compared to a lower cost $150 Thunderbolt in terms of phase noise or  
 stability 
 of course, and they have CMOS 10MHz outputs, but then the  TB's cost around 
 $1500 new I guess.
 
 We think the GPSTCXO's and LC_XO type units will work quite well  wherever 
 standard OCXO's are used today, and power/size/weight are an  issue.
 
 Bye,
 Said
 
 
 In a message dated 10/2/2012 14:21:47 Pacific Daylight Time,  
 paulsw...@gmail.com writes:
 
 Said
 I have to say I was looking through the list of modules  that are available.
 I guess a couple of things really jump out.
 The low  power consumption and what you get in terms of behaviors. It is
 pretty  amazing actually. Though I have my power sucking Tbolt and 3801.
 But I  could easily see for a Amateur radio operator just getting into  time
 nuttery that these might be a nice way to go. I guess that would open  an
 interesting debate. Getting the used RBs at Hamfest of questionable  quality
 for $200 or far less. Or something modern and simply  works.
 Regards
 Paul.
 
 ___
 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.

___
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.

Re: [time-nuts] Austron Model 6016 Frequency Multipler - free to a good home

[Brian, WA1ZMS]

I have one of those myself.
I have been looking for a schematic.  Does anybody have one?
Better yet, a full manual!


-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Louis Mamakos
Sent: Wednesday, September 26, 2012 2:40 PM
To: Discussion of precise time and frequency measurement
Cc: Doug Humphrey
Subject: [time-nuts] Austron Model 6016 Frequency Multipler - free to a good
home

Hi!  I've been a lurker on time-nuts for some years now, largely because of
an unhealthy preoccupation with time synchronization with NTP over the last
couple of decades.

A buddy of mine is clearing out a bunch of hardware he's accumulated over
time, and has an Austron Model 6016 Frequency Multiplier that's up for
grabs and free to a good home.  It is physically located in Laurel, MD and
you can contact Doug directly for subsequent offers if interest.  It looks
to be physically in good condition.

There's a photo attached (which may not survive the mailing list), and I've
also put the image up here:
http://www.transsys.com/louie/tmp/austron6016.jpg

Please follow-up with Doug Humphrey d...@joss.com directly if you're
interested.

Louis Mamakos

___
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.


___
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.

Re: [time-nuts] Javad Letter to FCC...

[Brian, WA1ZMS]

He seems to give no specs on group delay.
That is very critical for timing applications, but not much of an issue for
your iPhone if you don't mind yet another 10m of error.

My 2 cents...

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Scott McGrath
Sent: Tuesday, September 25, 2012 8:23 PM
To: Discussion of precise time and frequency measurement
Cc: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Javad Letter to FCC...

Is he going to retrofit every GPS dependent device already in service for
free???

   I'm also suspicious of the steepness of the filter skirts.  They seem to
be too good to be true and I've looked at a lot of filters through multiple
VNA's and scalar analyzers

Ou

Sent from my iPhone

On Sep 25, 2012, at 9:59 AM, Rob Kimberley robkimber...@btinternet.com
wrote:

 http://www.gpsworld.com/javad-asserts-filters-protect-gps-l1-l2-l5-gl
 onass-
 l1-l2-galileo-l1-l5/
 
 I'm wondering how much LightSquared are paying this guy?
 
 Rob
 
 
 
 
 ___
 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.

___
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.


___
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.

[time-nuts] HP OCXO in 5016A.....

[Brian, WA1ZMS]

Does anyone has any info on the HP-00105-6013 Series 1248

OCXO that is/was used in the HP-5061A?

 

I have a newly acquired 5061A that has issues.

It has an FTS tube in it, and while there is beam current

and plenty of 2nd Harmonic, the alarm light does goes out,

but this unit is not yet a member of the Green Light Club

in that the continuous operation light fails to light.

 

The control loop appears to try and slew the OCXO

way off frequency.  My best guess is a defective A7

AC amp module.

 

Time to trouble shoot! :- )

 

Comments welcome.

 

-Brian, WA1ZMS/4

 

 

 

___
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.

Re: [time-nuts] HP OCXO in 5016A.....

[Brian, WA1ZMS]

Joe-

I have the manual. I trimmed the OCXO against my Z3801A before closing the
loop. That's when the slew took place, after loop was closed.
Green light bulb is OK. :-)


Sounds like A8 is the issue. Although the 2nd harmonic value (A7) is not as
stable as my other 5061A is when loop is closed. Could be a clue.
Time to get it up on- blocks on the bench and see just what is going on.

Thanks to all! :-)


-Brian, WA1ZMS

-Original Message-
From: J. L. Trantham [mailto:jlt...@att.net] 
Sent: Tuesday, September 11, 2012 6:07 PM
To: wa1...@att.net; 'Discussion of precise time and frequency measurement'
Subject: RE: [time-nuts] HP OCXO in 5016A.

Brian,

Do you have a GPSDO?  If so, with the Loop Open, you can adjust the OCXO to
exactly 5 MHz and watch that it is stable.  Once done, then select Oper and
wait until Beam I and 2nd Harmonic come up.  Then hit the Reset Button and
watch what happens to the 5 MHz, compared to your GPSDO.  If it slews off
frequency, then it shows a signal is getting to the OCXO and, likely, A9 is
OK.  If it stays put, A9 could be a problem.  If the 2nd Harmonic falls when
you turn off MOD, then A7 is likely OK and the problem is more likely in A8.

Also, when you unplug J1 from A7, Beam I and 2nd Harmonic should fall.  If
so, A7, again, is likely OK.

I have also had failures in A14.  Make sure the bulb is not burned out.

Do you have a manual?

Good luck.

Joe

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Brian, WA1ZMS
Sent: Tuesday, September 11, 2012 4:50 PM
To: Time-Nuts
Subject: [time-nuts] HP OCXO in 5016A.

Does anyone has any info on the HP-00105-6013 Series 1248

OCXO that is/was used in the HP-5061A?

 

I have a newly acquired 5061A that has issues.

It has an FTS tube in it, and while there is beam current

and plenty of 2nd Harmonic, the alarm light does goes out,

but this unit is not yet a member of the Green Light Club

in that the continuous operation light fails to light.

 

The control loop appears to try and slew the OCXO

way off frequency.  My best guess is a defective A7

AC amp module.

 

Time to trouble shoot! :- )

 

Comments welcome.

 

-Brian, WA1ZMS/4

 

 

 

___
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.


___
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.

Re: [time-nuts] HP10514B Mixer Terminations

[Brian, WA1ZMS]

Bruce is correct. For best RF performance in an rf environment
the use of 50ohms for all ports is a
good start. However, even in RF designs
you can often optimise a mixer spec
with something other than 50 ohms.

With a VLF IF freq like a DMTD, each
mixer model might have an ideal
termination impedance. Steve Mass' book on RF mixers is good for typical
mixer applications but the NIST papers
are better for DMTD uses.

In the mm-wave work I have done, the
first place to start is to increase LO
power until the s11 of the IF port starts
to look like a good match for the IF pre-amp. So each application of a mixer
can often be based around what you
are doing with it.

Each time I use one, I learn a new
fact! :-). Great hobby!

-Brian, WA1ZMS/4

On Sep 9, 2012, at 4:41 PM, Bruce Griffiths bruce.griffi...@xtra.co.nz wrote:

 David Kirkby wrote:
 On 9 September 2012 18:28, Pascual Arbonap.arb...@securimar.com  wrote:
   
 
 Hello Brian,
  I am a radio amateur and and also in the Time nuts list,  At 
 the moment I am planning to bild a DMTD for experimentation. and as you 
 have a nice experience in this field , for me will be very wellcame your 
 help. My ask is ¿whitch is te best temination for the mixer? (FI 10Hz or 
 100Hz)  ¿what about the amp, limiters and zero crosing detec.)
 
 Mixers should be terminated in 50 Ohms - at least at all frequencies
 where there is an output. Someone mentioned minicircuits. They sell
 constant impedance filters, where the impedance in the both the
 passband and stopband are 50 Ohms. Most filters have a impedance far
 away from 50 Ohms in the stopband.
 
   
 This is an often repeated fallacy.
 For low IF frequencies such as in a DMTD, a reactive IF termination can have 
 the advantage of lower noise and larger IF signal slew rate.
 The resultant reduction in RF and LO port VSWR is easily corrected (at least 
 for low RF and LO frequencies) with a series resistor and/or resistive pad.
 There are a number of NIST papers on the effect of mixer termination for 
 DMTDs and phase noise measurements.
 The minicircuits phase detectors (actually specialised mixers) are specified 
 for use with 500 ohm IF terminations.
 I don't know the details of what you are trying to do, but keep in
 mind what I said.
 
 Dave
 
 ___
 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.
 
   
 Bruce
 
 ___
 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.

___
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.

[time-nuts] {OT} e-mail testing only....

[Brian, WA1ZMS]

Just testing.

 

My cloud/web based ATT e-mail address book was hacked.

ATT now has e-mail servers run by Yahoo. Drat!

 

Yahoo has a gaping security hole.  My PW was not

hacked, but my address book in cloud storage was

used to send out spam. It was not a full copy of my

real address book, but enough to cause me much

damage control effort today.

 

All PWs have been changed yet again to be sure, but the

cloud address book has also been deleted.  So much for web-

based or cloud based address books.  Back to local PC

and iPhone only address books for me. No iCloud either.

 

MY DEEPEST AND SINCERE APPOLOGIES TO ALL!

I am embarrassed. 

 

My first and only hack in 20+ years of e-mail. So I guess

I was overdue. Yahoo/ATT today. When will G-Mail get hit? :- )

 

Life in a modern spam rich world.

 

73,

-Brian, WA1ZMS

 

(If you don't see this signature line, it's not me.

Just delete it please.)

 

___
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.

Re: [time-nuts] Advice on Austron 1250A

[Brian, WA1ZMS]

I bought one of late that was mint NIB.  Paid more than your price for it
and am happy with mine.
So for $250 to play around with and see if its phase noise is better than
another osc, it would be
worth it IMHO.

If you don't like it, but it works fine, I'm sure you can flip it for what
you have into it.

Besides...they make a good all-in-one box that you can play around with ext
locking and learn.
And rememberExperience is something you always get, AFTER you needed
it! :- )

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dave M
Sent: Saturday, August 18, 2012 9:24 PM
To: FEBO Time Nuts
Subject: [time-nuts] Advice on Austron 1250A

Does anyone in the group have any experience or advice on the Austron 1250A
Crystal Frequency Standard?  I have a chance to buy one for $250 tomorrow at
a local hamfest, but can't find anything in the archives on them.  It's very
clean, and the seller says that it is in perfect working order.  He's local
to the area, so I can easily get back with him in case of troubles.
I have a PDF of the manual, so maintenance shouldn't be a problem (barring
parts unavailability).
Good deal, or pass it up for a lower priced unit?  Or recommendations for a
different mfr/model?  Price is a consideration; that's one of the reason I'm
interested in this unit.

Manual states long-term stability of 5x10e-11 per day after 90 days.

Thanks for advice,
Dave M
___
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.


___
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.

Re: [time-nuts] FRK specs.....

[Brian, WA1ZMS]

Thanks Tom.  

I agree, the SRS seems to be the best
overall Rb except maybe on old HP if one is willing to spend about the same 
price on a 20 year old unit.  The SRS units I bought for work were only $2700 
with chassis, rack ears and multiple outputs.



-Brian, WA1ZMS

On Aug 12, 2012, at 3:17 AM, Tom Knox act...@hotmail.com wrote:

 
 Hi Brian;
 There are a few decent rubidium oscillators short term like the SRS but none 
 are great, in my humble opinion you are much better off disciplining a good 
 quartz oscillator off your LPRO.
 Best Wishes;
 Thomas Knox
 
 
 
 From: wa1...@att.net
 Date: Sat, 11 Aug 2012 21:56:13 -0700
 To: time-nuts@febo.com
 Subject: [time-nuts] FRK specs.
 
 I used to be of the opinion that the Efratom FRK-H was the best of the 
 models of FRK Rb standards for both short-term stability and overall 
 performance.
 
 Is that still true today?
 
 I know there are better solutions for short-term (BVA OCXO) and long term
 (Cs  MASERS). But where to things stack up today?
 
 I'm looking to buy an Rb that's better than my LPROs and other models.
 But I do not own an FRK-H.
 
 Looking for comments, please.
 
 Thanks in advance,
 -Brian, WA1ZMS
 ___
 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.
 
 ___
 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.

___
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.

Re: [time-nuts] FRK specs.....

[Brian, WA1ZMS]

Me too, please.


-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of dlewis6...@austin.rr.com
Sent: Sunday, August 12, 2012 2:55 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] FRK specs.


Bert:
Interesting.

I, too, have a couple of the HP 10811 oven-oscillators sitting on the shelf
for several years, waiting for a project. I want to 'discipline' them,
but really do not know how.

Could you kindly mark up the HP 10811 schematic and/or please tell me what
to cut, ... what to jumper???

Thanks a lot!

Don Lewis
Austin, TX




--





==

 ewkeh...@aol.com wrote:
 In the commercial world a PRS10 is most likely the best but for time 
 nuts even at the surplus price in my opinion it is all hype and a 
 waste of money. Have you looked closely at the specification and the 
 design. Frequency accuracy can not be better than 1 E-12 since the 
 OCXO is driven strictly by a DAC and the A/V is for time nuts nothing 
 to write home about. Any digital loop controlling a Rb in tern with an 
 analog loop controlling a selected HP 10811 or for that matter a Morion
will outperform a PRS 10.
 I have a FRK-H controlling a HP 10811 that has an A/V below 1 E-12 
 from 1 to 100 seconds, I modified the FRK loop and the 10811. On the 
 10811 it is easy to get to the bottom PCB and without un soldering any 
 component or further disassembly cutting two traces and two jumpers 
 you end up with a 2 to 12 Volt tuning voltage, perfect for a FRK or 
 M100.. A second option is to use a separate analog loop with a time
constant suitable for your OCXO.
 By the way the FRK-H is not lower noise but factor 2 lower aging with 
 the proper OCXO not an issue, since hopefully you discipline it with GPS.
 For 12 years I have used Shera in that application recently switching 
 the DAC to a LTC1655. Has served me well over the years.
 Other Rb's will do also a very credible job. On one extreme a FEI 5680 
 is waiting to be integrated with a MV180 on the other extreme a HP5065 
 RVFR assembly will be integrated with a M1000 OCXO along with state of 
 the art circuitry.
 Bert Kehren



 In a message dated 8/12/2012 8:09:54 A.M. Eastern Daylight Time, 
 wa1...@att.net writes:

 Thanks Tom.

 I agree, the SRS seems to be the best
 overall Rb except maybe on old HP if one is willing to spend about the 
 same price on a 20 year old unit. The SRS units I bought for work were 
 only
 $2700 with chassis, rack ears and multiple outputs.



 -Brian, WA1ZMS

 On Aug 12, 2012, at 3:17 AM, Tom Knox act...@hotmail.com wrote:

 
  Hi Brian;
  There are a few decent rubidium oscillators short term like the SRS 
  but
 none are great, in my humble opinion you are much better off 
 disciplining a good quartz oscillator off your LPRO.
  Best Wishes;
  Thomas Knox
 
 
 
  From: wa1...@att.net
  Date: Sat, 11 Aug 2012 21:56:13 -0700
  To: time-nuts@febo.com
  Subject: [time-nuts] FRK specs.
 
  I used to be of the opinion that the Efratom FRK-H was the best of 
  the
 models of FRK Rb standards for both short-term stability and overall 
 performance.
 
  Is that still true today?
 
  I know there are better solutions for short-term (BVA OCXO) and 
  long
 term
  (Cs  MASERS). But where to things stack up today?
 
  I'm looking to buy an Rb that's better than my LPROs and other models.
  But I do not own an FRK-H.
 
  Looking for comments, please.
 
  Thanks in advance,
  -Brian, WA1ZMS
  ___
  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.
 
  ___
  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.

 ___
 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.

 ___
 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.
___
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.


___
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.

[time-nuts] FRK specs.....

[Brian, WA1ZMS]

I used to be of the opinion that the Efratom FRK-H was the best of the models 
of FRK Rb standards for both short-term stability and overall performance.

Is that still true today?

I know there are better solutions for short-term (BVA OCXO) and long term
(Cs  MASERS). But where to things stack up today?

I'm looking to buy an Rb that's better than my LPROs and other models.
But I do not own an FRK-H.

Looking for comments, please.

Thanks in advance,
-Brian, WA1ZMS
___
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.

Re: [time-nuts] Lightsquared questionfor SFO area....

[Brian, WA1ZMS]

Nigel-

I remember that event.  This issue I'm remotely dealing with now seems to be
limited to a specific local
area bounded by a few km.   So local QRM is possible.  On Saturday the techs
will install all new GPS antennas with
integrated band-pass filters.

Conf call on Saturday night at 6pm my time will produce more date.

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of gandal...@aol.com
Sent: Saturday, July 28, 2012 2:27 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Lightsquared questionfor SFO area

This is one well documented example of an earlier unintentional jamming
incident.
 
_http://www.gpsworld.com/gnss-system/signal-processing/the-hunt-rfi-776_
(http://www.gpsworld.com/gnss-system/signal-processing/the-hunt-rfi-776) 
 
Regards
 
Nigel
GM8PZR
 
 
In a message dated 28/07/2012 02:43:23 GMT Daylight Time, wa1...@att.net
writes:

Does  anyone know if there is ANY recent active Lightsquared testing taking
place  in the SFO area of the US?

I'm dealing with a day-job issue with GPS  clocks in the Bay Area showing
GPS unlocked errors from 3rd party  equipment.

-Brian,  WA1ZMS



___
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.

___
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.


___
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.

[time-nuts] Lightsquared questionfor SFO area....

[Brian, WA1ZMS]

Does anyone know if there is ANY recent active Lightsquared testing taking
place in the SFO area of the US?

 

I'm dealing with a day-job issue with GPS clocks in the Bay Area showing
GPS unlocked errors from 3rd party equipment.

 

 

 

-Brian, WA1ZMS

 

___
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.

Re: [time-nuts] Lightsquared questionfor SFO area....

[Brian, WA1ZMS]

Jim-

That's one thing I was afraid of, but did not yet mention to our mgmt. team.
But if Light squared lost their Part 5 license, then I can take them off the
list.
It's a complicated problem that due to the nature of it, I cannot discuss on
the reflector.

But I'm involved via remote reporting from techs out in the field and their
daily reports and conference calls.
So I just need to due engineering diligence as I try and help them. 

I expect my butt will be on a plane next week unless I can identify a 3rd
party vendor equipment problem.

THANKS!


-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Jim Lux
Sent: Saturday, July 28, 2012 12:35 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Lightsquared questionfor SFO area

On 7/27/12 6:42 PM, Brian, WA1ZMS wrote:
 Does anyone know if there is ANY recent active Lightsquared testing 
 taking place in the SFO area of the US?



Very unlikely.. they've lost their experimental license.


 I'm dealing with a day-job issue with GPS clocks in the Bay Area 
 showing GPS unlocked errors from 3rd party equipment.




there are myriad sources of interference out there.  Jammers are a BIG
problem in urban areas (truckers and cab drivers use them to defeat their
GPS based tracking systems and time clocks).

there's a great set of articles over the past few months in GPS World about
it.







 -Brian, WA1ZMS



 ___
 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.




___
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.


___
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.

[time-nuts] [OT]: HP-5061A and a dust bunny.....

[Brian, WA1ZMS]

This was such a crazy event that I have to share this with somebody.

 

I started to notice an odd smell in the ham shack/lab yesterday night.

Now we had a bad weather storm and was one of 2.5 Million homes

without AC power for 5 days.  So the generators were pressed into

service and kept the lab cool with a 9,000BTU room air conditioner.

 

My first thought was mold in the temporary A/C unit. But after the

family came home from church it was very clear that it was much

worse than a simple mold issue. It was the smell of a dead rodent.

It had to be. I recognized it by then.

 

So the hunt was on!  Where was the dead mouse or mole that

one of our cats must have dragged in through the pet door?

 

The astute may already know the answer:  In the bottom of a

rack where an HP-5061A lives was not only the typical “dust

bunnies” that often collect in such areas…….BUT……..
there was also a dead rabbit! 

 

BTW….All 3 cats have been interviewed and none will admit to

being involved in any way.

 

 

-Brian, WA1ZMS/4

Forest, VA ßwhere the AC mains are back on and the venting

of the shack/lab continues with an outside air temp of 38C.

No kidding!  What’s worse the heat or the smell? Both will kill

you.

 

 

___
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.

Re: [time-nuts] US 5065A standby battery cell source?

[Brian, WA1ZMS]

A US East Coast chain of stores called Batteries Plus can sell you cells and
spot weld them in any almost any way you want.
At least my local store can do that here in Virginia.


-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dan Rae
Sent: Sunday, July 01, 2012 7:41 PM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] US 5065A standby battery cell source?

All this discussion of the excellence of these Rb units reminds me that
another cell must have died in my battery pack since the slightest glitch in
the power here now makes the green light go out.  The last time a cell died
I just took it out since it actually seems to work well enough with 20
instead of the specified 21, but another one seems to have gone high
resistance.

So, my question is: where might be a good place in the US to get tabbed 
NiMH AA cells to replace the battery in mine?   I am currently using 
generic Chinese ones, but am not at all happy with their longevity.

And this one came from eBay, quite a bit less than $500 because it looked
filthy, but it took a lot of patience to find it and a bit of TLC to get it
going, but it has been working superbly for about four years now.

Dan





___
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.


___
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.

Re: [time-nuts] ACTS leap second caught!

[Brian, WA1ZMS]

I caught a nice video of my GSP LED display as driven by the GPS engine in my 
Z3801A showing the leapsecond.

I can up load it later. The WWV audio
got very noisy at that moment. Root cause is all of the generator QRM in the 
neighborhood since I live right in the middle of the 2.5Million homes in VA
as of last night who have no commercial utility power. Could be days before we 
get AC power back! 

So far, my generator is keeping parts of the house cool as well as the ham 
shack.


-Brian, WA1ZMS/4 Forest, VA


On Jun 30, 2012, at 8:05 PM, Scott Newell newell+timen...@n5tnl.com wrote:

 National Institute of Standards and Technology
 Telephone Time Service, Generator 1c
 Enter the question mark character for HELP
D  L
 MJD  YR MO DA HH MM SS ST S UT1 msADV OTM
 
 56108 12-06-30 23:59:35 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:36 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:37 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:38 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:39 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:40 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:41 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:42 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:43 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:44 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:45 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:46 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:47 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:48 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:49 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:50 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:51 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:52 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:53 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:54 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:55 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:56 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:57 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:58 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:59 50 1 -.6 045.0 UTC(NIST) *
 56108 12-06-30 23:59:60 50 1 -.6 045.0 UTC(NIST) *
 56109 12-07-01 00:00:00 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:01 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:02 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:03 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:04 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:05 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:06 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:07 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:08 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:09 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:10 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:11 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:12 50 0 +.4 045.0 UTC(NIST) *
 56109 12-07-01 00:00:13 50 0 +.4 045.0 UTC(NIST) *
 
 
 ___
 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.

___
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.

Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

[Brian, WA1ZMS]

At the risk of over simplifying it: Doesn't it all always depend on the loop
BW you pick?

Inside the loop BW you see the noise of the loop's reference. Outside the
loop BW you see the free running noise of the oscillator.
At and around the loop's corner frequency you see a combination of both.
The choice of loop BW depends on what Tau you want
and what grade of Rb you are trying to improve.

But as PHK said, the article was a bit thin on details.


-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Azelio Boriani
Sent: Thursday, May 03, 2012 6:06 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

OK, I've read the paper. Why not GPSDiscipline your Rb? GPSDiscipline cum
grano salis but do it. My LPFRS GPS disciplinator hardware is ready. OK, I
know, the 1E-11 step is too large but I'll try. First I'll take measurements
so that I can think about a disciplining algorithm. Then a hardware
modification on the LPFRS to get access to the C-field could make it better.

On Thu, May 3, 2012 at 11:29 PM, Poul-Henning Kamp
p...@phk.freebsd.dkwrote:


 This is pretty think, but interesting:

 http://tf.nist.gov/sim/Papers/Trigo_CPEM_2010.pdf

 --
 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.

 ___
 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.

___
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.


___
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.

Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

[Brian, WA1ZMS]

All good points, and all very true.

I often remind myself of how over simplified sometimes people view things.
Case in point:
I once had a high level manager hold an all employee meeting in which he
started his talk by saying that
Nothing difficult is ever easy.   Needless to say...he didn't last
long in his job and left the company.

-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Bob Camp
Sent: Thursday, May 03, 2012 7:42 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

Hi

If you dig into commercial GPSDRb's their loop time constants are *very*
long. They crank out to a couple days fairly quickly. In addition they (like
a lot of GPSDO's) have lowpass filters in the loop in addition to the basic
PLL /  FLL structure.

Bob

On May 3, 2012, at 6:30 PM, Azelio Boriani wrote:

 And maybe the problem is worse: I want also to keep aligned the PPS. 
 To recover the PPS position (without phase jumps) it is mandatory to 
 slightly force the 10MHz. Better start the machine and take measures...
 
 On Fri, May 4, 2012 at 12:20 AM, Brian, WA1ZMS wa1...@att.net wrote:
 
 At the risk of over simplifying it: Doesn't it all always depend on 
 the loop BW you pick?
 
 Inside the loop BW you see the noise of the loop's reference. Outside 
 the loop BW you see the free running noise of the oscillator.
 At and around the loop's corner frequency you see a combination of both.
 The choice of loop BW depends on what Tau you want and what grade of 
 Rb you are trying to improve.
 
 But as PHK said, the article was a bit thin on details.
 
 
 -Brian, WA1ZMS
 
 -Original Message-
 From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] 
 On Behalf Of Azelio Boriani
 Sent: Thursday, May 03, 2012 6:06 PM
 To: Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...
 
 OK, I've read the paper. Why not GPSDiscipline your Rb? GPSDiscipline 
 cum grano salis but do it. My LPFRS GPS disciplinator hardware is 
 ready. OK, I know, the 1E-11 step is too large but I'll try. First 
 I'll take measurements so that I can think about a disciplining 
 algorithm. Then a hardware modification on the LPFRS to get access to 
 the C-field could make it better.
 
 On Thu, May 3, 2012 at 11:29 PM, Poul-Henning Kamp
 p...@phk.freebsd.dkwrote:
 
 
 This is pretty think, but interesting:
 
 http://tf.nist.gov/sim/Papers/Trigo_CPEM_2010.pdf
 
 --
 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.
 
 ___
 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.
 
 ___
 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.
 
 
 ___
 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.
 
 ___
 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.


___
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.


___
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.

[time-nuts] Z3801A......????

[Brian, WA1ZMS]

Bob-

I have a spare that i need to test and make sure all is OK.

Any interest?
Make me an offer and it's yours after I get time to test is out.


-Brian, WA1ZMS

On Feb 17, 2012, at 4:56 PM, bownes bow...@gmail.com wrote:


___
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.

Re: [time-nuts] Z3801A......????

[Brian, WA1ZMS]

Sorry for band width to group!
Stupid iPhone! :-)


-Brian, WA1ZMS

On Feb 17, 2012, at 5:15 PM, Brian, WA1ZMS wa1...@att.net wrote:

 Bob-
 
 I have a spare that i need to test and make sure all is OK.
 
 Any interest?
 Make me an offer and it's yours after I get time to test is out.
 
 
 -Brian, WA1ZMS
 
 On Feb 17, 2012, at 4:56 PM, bownes bow...@gmail.com wrote:
 
 
 ___
 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.

___
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.

Re: [time-nuts] Removing thermal tape residue?

[Brian, WA1ZMS]

FWIWI used denatured alcohol and acetone.  Just be sure to wear chemical
safe gloves and plenty of shop rags.
But it comes right off. Fumes are bad too.

Let the rags dry out before you put them in the trash.

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Graham / KE9H
Sent: Saturday, February 11, 2012 12:11 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Removing thermal tape residue?

John:

If it is an adhesive tape residue or just an adhesive residue, the best,
paint safe, and non-toxic remover I am aware of is Goo-Gone.  It is some
kind mild solvent with a lot of citrus oil in it.  Sold at grocery stores.
Since you own a house, I would be surprised if your wife does not already
have a bottle.  It is impossible to operate a house without it.

Works extremely well on adhesive tape residue, stick-on label residue, and
windshield sticker residue.

If that doesn't work then try iso-propyl alcohol, acetone, tri-chlor, etc.
Those are more toxic, will attack plastic and paint, etc.

--- Graham / KE9H

==


On 2/11/2012 10:56 AM, John Ackermann N8UR wrote:
 I wasn't clear below -- the residue is on the Rb exterior surface that
attached to the heatsink.

 On Feb 11, 2012, at 11:52 AM, John Ackermann  N8URj...@febo.com  wrote:

 Is there a recommended way to remove the residue of what I presume was
thermal tape on the heatsinks of my various telco Rb units?  It's a slightly
tacky light greenish layer.  I'm guessing that for a permanent installation
one would want to remove that residue, smooth the surface, and replace with
new material for best thermal transfer to the heatsink.

 John
 ___
 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.
 ___
 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.



___
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.


___
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.

Re: [time-nuts] Rubidium Performance

[Brian, WA1ZMS]

Thanks John!


-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of John Ackermann N8UR
Sent: Friday, February 03, 2012 9:41 PM
To: Time-Nuts
Subject: [time-nuts] Rubidium Performance

Someone earlier today made the point that for all the talk about the FEI
rubes, there hasn't been any real performance info posted.  That prodded me
to start an experiment I've been meaning to do for a while.  I have samples
of all three of the common telco Rb standards -- Efratom FRS, Datum LPRO,
and Fe8-5680.

Over the next couple of days I'll do measurement runs of each of the three
versus an HP-5065A laboratory Rb (for ADEV), and a Wenzel ULN (for phase
noise).  I'll collect long enough to get solid ADEV out to at least 1000
second tau on each unit.  I have the FRS test running now.

If all goes well, I'll post the results early next week.

John
___
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.


___
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.

Re: [time-nuts] FE-5680A what is the size of the Torx??

[Brian, WA1ZMS]

I used a T7 bit for mine.

-Brian, WA1ZMS

On Jan 17, 2012, at 6:24 PM, Paul F. Sehorne p...@sehorne.org wrote:

 Nope.  Looked at them with a jeweler's loupe.  They are Torx.
 
 On 1/17/2012 5:13 PM, Peter Gottlieb wrote:
Most likely they are 1/16 hex.
 
 
On 01/17/12, Chris Albertsonalbertson.ch...@gmail.com  wrote:
 
No need to buy a tool. They drill out really easy but you can also
simply punch them out. There are no nuts on the back. The screws
bite directly into the fiberglass PCB. Mine were T-16 but many
people report they are hex not torx. Maybe it depends on what kind
of screw they had around the day it was built.
On Tue, Jan 17, 2012 at 2:42 PM, Paul F. Sehorne[1]p...@sehorne.org
wrote:

  I received my two FE-5680s today.  The first thing I want to do is
inspect
  the insides.  The smallest Torx I have is a too-big T-8.  What size
is
  needed?  I'll need to do an internet search for the correct size.

  Thanks,
  Paul

  ___
  time-nuts mailing list -- [2]time-nuts@febo.com
  To unsubscribe, go to
  [3]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
  and follow the instructions there.
--
Chris Albertson
Redondo Beach, California
___
time-nuts mailing list -- [4]time-nuts@febo.com
To unsubscribe, go to
[5]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
 
 References
 
1. mailto:p...@sehorne.org
2. mailto:time-nuts@febo.com
3. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
4. mailto:time-nuts@febo.com
5. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
 ___
 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.
 
 
 ___
 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.

___
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.

Re: [time-nuts] 15 Seconds error...??

[Brian, WA1ZMS]

GPS has its own time scale.  Part of the GPS data stream contains the number
of seconds that GPS and UTC differ by.


-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Dan Rae
Sent: Monday, January 16, 2012 7:21 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 15 Seconds error...??

GPS time v. UTC ?

___
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.


___
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.

Re: [time-nuts] FE-5680A Mechanical Question

[Brian, WA1ZMS]

My rivets were tiny Torx screws.


-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of J. L. Trantham
Sent: Wednesday, January 11, 2012 9:22 PM
To: 'Discussion of precise time and frequency measurement'
Subject: [time-nuts] FE-5680A Mechanical Question

Should I ever have time to pursue the Rb unit, what happens when I 'drill
out' all the rivets that mount the unit to the PCB that it arrived on?  Any
reason to keep it on the PCB?

 

Does the bottom cover come off?  Will I need to replace the rivets with
something else to keep the bottom cover on?

 

Thanks in advance.

 

Joe

___
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.


___
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.

Re: [time-nuts] FE-5680A dumb question...

[Brian, WA1ZMS]

Thank you though. Got it working fine thanks to all the answers and help!

-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of gonzo .
Sent: Wednesday, January 04, 2012 2:18 AM
To: time-nuts
Subject: Re: [time-nuts] FE-5680A dumb question...


Hi Brian.
Taking the list concensus and confirming it on my recently arrived '5680A,
the pinout is as follows:

1. +15V  (1500mA cold: 800mA hot)
2. Gnd
3. Rb Lock (lock = low)
4. +5V  (~85mA)
5. Gnd
6. 1PPS  (high until Rb Lock goes low)
7. 10Mhz
8. RS323-RX
9. RS232-TX

These pinouts are not consistant across the FE-5680A range, but seems good
for the 'current batch' of cheap units coming out of china.

Cheers,
ian


 Date: Tue, 3 Jan 2012 20:58:10 -0500
 From: Brian, WA1ZMS wa1...@att.net
 To: Time-Nuts time-nuts@febo.com
 Subject: [time-nuts] FE-5680A dumb question...
 Message-ID: 01ccca84$4ff2d570$efd88050$@att.net
 Content-Type: text/plain; charset=us-ascii
 
 My E-bay FE-5680A finally arrived. (4weeks later)
 
  
 
 Of the pins on the DB-9 connector, which one is the RF output?
 
 The manual only talks about an SMA output.
 
  
 
 I know this has been talked about before, but I cannot find the thread.
 
  
 
 Thanks in advance  sorry for bandwidth,
 
 -Brian, WA1ZMS

  
___
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.


___
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.

[time-nuts] FE-5680A dumb question...

[Brian, WA1ZMS]

My E-bay FE-5680A finally arrived. (4weeks later)

 

Of the pins on the DB-9 connector, which one is the RF output?

The manual only talks about an SMA output.

 

I know this has been talked about before, but I cannot find the thread.

 

Thanks in advance  sorry for bandwidth,

-Brian, WA1ZMS

 

___
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.

[time-nuts] Question.....

[Brian, WA1ZMS]

OK..here's a question I never found a solid answer to:

On the HP-8656A signal generators, one of the amplitude scale buttons is in
dBf.

dB relative to a femptowatt.  (ie: -120dBm)

 

What drove that requirement?   I have yet to see a later vintage sig gen use
that scale.

 

 

-Brian, WA1ZMS

 

___
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.

[time-nuts] synch for pendulum clock....

[Brian, WA1ZMS]

This was talked about several years ago, but did anyone get a fully functional 
design running using electromagnets to synch at one or both ends of the travel?

In the meantime I am using a sensor to measure the time period of the pendulum 
for this particular new grandmother wall clock and from that, I can synthesize 
a pulse train from one of the 10MHz lab clocks to drive the electromagnets to 
cause a subtle synch at the end(s) of the pendulum travel. The pulse train freq 
is custom for a given clock.

Anyway.. that's my scheme for now.
Feedback welcome.

-Brian, WA1ZMS
___
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.

Re: [time-nuts] synch for pendulum clock....

[Brian, WA1ZMS]

Thanks guys.   Got the info I had been looking for. This group is a great
resource!
Only purpose for this project is so that the Westminster clock chimes at the
same exact moment at the GPS driven UTC LED display in the lab shows the
quarter hour.
Why

Why not!  :- )



-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Don Latham
Sent: Sunday, December 11, 2011 5:14 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] synch for pendulum clock

Try:
http://www.bmumford.com/clocks/hj/hj0199.html

and similar stuff found by googling driving pendulum clock
Lots of food for thought. Mumford has put some thought into it.
A lot depends on why you want to drive the thing; e.g. measuring
perturbations in the gravitational field, a sensitive barometer, temperature
sensor, etc. etc.
Don


___
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.

Re: [time-nuts] synch for pendulum clock....

[Brian, WA1ZMS]

Jim-

As soon as I hit the send icon, I knew I should have been more specific! :-)

How about this...when I'm in the ham shack and I hear the clock down the
hall (approx. 10mtrs away) chime, I'd like to be able to glance up at the
large LED display at the top of one of the test equipment racks I have and
see that at least the minute's digits read either: 00, 15, 30, or 45.   And
FWIWthe LED display is driven by the NMEA data coming out of the GPS RX
inside a Z3810A.

How's that?


-Brian, WA1ZMS


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Jim Lux
Sent: Sunday, December 11, 2011 9:39 PM
To: time-nuts@febo.com
Subject: Re: [time-nuts] synch for pendulum clock

On 12/11/11 5:53 PM, Brian, WA1ZMS wrote:
 Thanks guys.   Got the info I had been looking for. This group is a great
 resource!
 Only purpose for this project is so that the Westminster clock chimes 
 at the same exact moment at the GPS driven UTC LED display in the lab 
 shows the quarter hour.
 Why

 Why not!  :- )


I'm more concerned about your glib statement of same exact moment... 
we'll have none of this same exact stuff without careful specification of
the reference points, accounting for light time delay, etc.

Now, let's get right to it... on that chime... is it the time when the
hammer hits the bell, or when the peak of the first cycle occurs, or what?


Sounds like a cool idea...

Jim


___
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.


___
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.

[time-nuts] Looking for.....

[Brian, WA1ZMS]

Can anyone recommend a goid commercial grade freq ref synth that will generate 
a 10MHz output range with .1Hz step sizes based on a 10MHz ref?  Agilent sig 
gens are not a good fit for this application. Would like a 1 RU high compact 
box with PC programming.

I'm working an issue in my day-job around some RF simulcast tranmissions.

Thanks in advance. Contact off list please.

-Brian, WA1ZMS
___
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.

[time-nuts] Dead CBT

[wa1zms]

Paul-

Check rcvd. Thanks!

I your post where you wnted to talk to Corby. Maybe he can
work some life out of that tube.  Please let me know.

Alsoif you ever cut it open, remember to send me pix!

73,
-Brian, WA1ZMS


___
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.

[time-nuts] Free to good home.....

[Brian, WA1ZMS]

Cleaning out my storage area.

I have a know dead HP 05060-6090 CBT. SN: 1506A2030. Failure is hard and is one 
of the heating wires. Failed due to mechanical shock it seems. Was dead when I 
bought lot of equipment years ago.

It's free to a good home as display but it's heavy and would like to US address 
only if possible. You pay shipping.

Pleaee contact off-list if interested.

-Brian, WA1ZMS/4
Forest, VA
___
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.

Re: [time-nuts] Free to good home.....FOUND A HOME

[Brian, WA1ZMS]

The CBT has found a new home.

-Brian, WA1ZMS

On Aug 6, 2011, at 12:03 PM, Brian, WA1ZMS wa1...@att.net wrote:

 Cleaning out my storage area.
 
 I have a know dead HP 05060-6090 CBT. SN: 1506A2030. Failure is hard and is 
 one of the heating wires. Failed due to mechanical shock it seems. Was dead 
 when I bought lot of equipment years ago.
 
 It's free to a good home as display but it's heavy and would like to US 
 address only if possible. You pay shipping.
 
 Pleaee contact off-list if interested.
 
 -Brian, WA1ZMS/4
 Forest, VA

___
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.

Re: [time-nuts] Free to good home.....

[wa1zms]

I'm sorry. Somebody else beat you to it. :-(
Thank you, however.

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On
Behalf Of dlewis6767
Sent: Saturday, August 06, 2011 5:53 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Free to good home.


Yes, pls, ...how much to send to Austin, ...TX.

I might want it.






-Original Message-
From: Brian, WA1ZMS
Sent: Saturday, August 06, 2011 11:03 AM
To: Time Nuts
Subject: [time-nuts] Free to good home.

Cleaning out my storage area.

I have a know dead HP 05060-6090 CBT. SN: 1506A2030. Failure is hard and is
one of the heating wires. Failed due to mechanical shock it seems. Was dead
when I bought lot of equipment years ago.

It's free to a good home as display but it's heavy and would like to US
address only if possible. You pay shipping.

Pleaee contact off-list if interested.

-Brian, WA1ZMS/4
Forest, VA
___
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.


___
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.


___
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.

Re: [time-nuts] GPS interference and history...

[WA1ZMS]

bob-

you coming to greylock?


-Brian, WA1ZMS

On Jun 11, 2011, at 12:13 AM, bownes bow...@gmail.com wrote:



That small hemispherical antenna could also have been 900mhz. I have  
one here @ home that is a combined gps/900mhz antenna from an  
ambulance tracking system.



On Jun 10, 2011, at 22:01, Hal Murray hmur...@megapathdsl.net wrote:



li...@rtty.us said:
There's an enormous amount of gear out there that gets timing off  
of GPS.


That's an interesting claim.  Does anybody have any data on the  
usage of GPS

for timing?

I assume there is one in every cell tower and one in every 911 call  
center.

Are there other large categories of users?

What would it cost to replace all of it?  If you wanted to do  
something like
that, what would it cover?  How about people like us running old  
recycled

gear?  (Z3801A, ThunderBolt, ...)


I think I saw one last week.  It was on a river level measuring  
station on
the Sacramento River.  It was a small block building.  There was an  
antenna
pointing up into the sky.  I assume there is a satellite up there.   
There was
also a small (~3 inch dia) hemisphere antenna. I assume it was  
GPS.  (They
had power going into the building (no solar panels) so it should  
have been

simple to get a phone line too.)

I'm not sure why they need GPS at the recording house.  They know  
where it is
so timing is the only use I can think of.  But they could also get  
that at

the receiving end.  Millisecond accuracy isn't helpful.  Second level
accuracy might be interesting if something breaks and you want to  
know when
the wave got to downstream stations.  The risetime is probably over  
a second.



--
These are my opinions, not necessarily my employer's.  I hate spam.




___
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.


___
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.


___
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.

Re: [time-nuts] From GPS World - Lightsquared ...

[wa1zms]

If you think you're being tracked by the police or
a private-eye (ie: ugly divorce!) one might think
that a GPS jammer would be to their advantage.
Buy one on e-bay and you think all is OK.


-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On
Behalf Of Chris Albertson
Sent: Wednesday, February 09, 2011 8:42 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] From GPS World - Lightsquared ...


On Wed, Feb 9, 2011 at 8:23 PM, Charles P. Steinmetz
charles_steinm...@lavabit.com wrote:
 From a news release issued by the FCC today:

 The FCC Enforcement Bureau today announced new efforts to clamp down on
the
 marketing, sale, and use of illegal cellphone and GPS jamming devices.

Why would anyone jam GPS, other then because they want the bandwidth
for their own service.   What is the market for gps jamers.  Seems
silly you can't hide position or time

I can understand jamming cell phones, to keep the noise down in some
area or maybe stop them from being used in prisions or whatever
--
=
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.


___
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.

Re: [time-nuts] hp5061a/b no I beam current

[wa1zms]

I used the LF coil to test for beam I when I found a used tube. I was  
able to confirm it had Cs emission.


-Brian, WA1ZMS

On Oct 19, 2009, at 10:28 PM, serv...@frequencystandards.com wrote:




  3. hp5061a/b no I beam current (paul swed)
Message: 3
Date: Sun, 18 Oct 2009 12:25:30 -0400
From: paul swed paulsw...@gmail.com
Subject: [time-nuts] hp5061a/b no I beam current
To: time-nuts@febo.com
Message-ID:
   ac803ca80910180925y78cf028ai31e6560554264...@mail.gmail.com
Content-Type: text/plain; charset=ISO-8859-1

Lets see if this works.
I am new to the time-nuts user group
Just obtained a HP 5061a CS standard. Pumps down very well to 0  
(Hard to

believe) But it did.
CS oven comes up to temp. But in operation no I beam current.
Noticed that the tube states -2083V multiplier. But its regulating to
-1606V
can adjust to 2083.
Still no current. Also no 2nd harmonic but with No I that's what I  
expect.

Its an interesting unit from the naval observatory.
I have the traditional 5061 a service manual. Its halfway between a  
A and

a
B unit.
As example A15 power reg is using ICs and I found a website with that
schematic.
The CS control board A11 also is using ICs at least 3 switching  
supplies

us
SG3524s
I would like to see a schematic of this if anyone has it. Though I  
suspect

that the CS board is fine.
I want to check several of the voltages though.
Any help would be appreciated.
Thanks


Paul, there are several different versions of the A15 board. To get  
the
correct schematic, you will need the part number which is etched on  
the
board. It will be something like 05061-6199. The series number will  
also
help. It may be on a sticker lable or etched, depending on the age  
of the

board.
The A11 module also has more than 1 version. 05061-06144 is the last  
one
if my memory serves right. Hopefully you don't have one with several  
round
epoxied transformers on it with lots of taps. If you do, that means  
you
have the old AC controller. You can probably tell that just by  
listening
for the whistle of it. The DC ones don't whistle. Since you said the  
Cs
oven comes up to a normal meter reading, you are probably safe in  
saying

that A11 is OK.
The first key though is to make sure that the 5Mhz oscillator is on
frequency. If it is very far off, you will not get 2nd harmonic or  
beam
current. If you are off even 1/2 hz, it is too much. I usually try  
to get

them within 3 millihertz before look8ing for beam current. Be careful
turning the coarse frequency adjust, it only takes a small fraction  
of a
rotation to make a very large frequency change. You can twist them  
off if

you try to turn too hard and are at the end of the adjustment range.
There are several sites hosted by Time nuts members that have  
manuals for
the 5061 scanned in. I dont believe any of them charge you to  
download a
copy. Don't remember off the top of my head which sites they are.  
Try to
find one as close to the series of your unit as possible. If not  
exact, go
for the next series up as they contain backdating info in all of  
them. If
you aren't familiar with finding the series, it is the first 4  
digits of

the serial numbers on the back of the unit. This does not mean all the
modules in the unit are this series, it is just the series of that  
unit.

Let us know how you make out.
Chuck Norton


___
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.


___
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.

Re: [time-nuts] DMTD phase shifter

[wa1zms]

bruce-

do you have a favorite ZCD schematic that you can share?

many thanks in advance!


-Brian, WA1ZMS

On Jul 25, 2009, at 9:36 AM, Bruce Griffiths  
bruce.griffi...@xtra.co.nz wrote:



Bert

If you intend to use a USB interface then its probably essential to  
use

an optical isolator or equivalent between the zero crossing detector
(ZCD) output and the counter input to minimise potential low frequency
ground loop problems. JPL found that low frequency ground loops limit
the performance if the zero crossing detector outputs aren't isolated
from each other.

A resolution of better than 1E-14/tau should be relatively easy to
achieve with a good ZCD design.
Maintaining such resolution for long tau will be dependent on the
stability of the mixer and ZCD temperatures.
Mixer drift can be as large as 10ps/C or more at 10MHz.
The tempco of the low pass filter components in the first few stages  
of

the ZCD will dominate the ZCD phase shift tempco.

Using a linear amplifier and filter in front of a zero crossing  
detector

built into the counter is not the best way to implement such a system.

The amplifier filter limiter chain should be designed to suit the  
offset

frequency.
The goal is to increase the zero crossing slope to a point where the
noise of the counter input circuitry doesnt contribute significant  
jitter.

To do this linear amplification is counterproductive, every stage of
slope amplification needs to incorporate a low pass filter and  
clamping

to reduce the output noise whilst increasing the output slew rate. As
long as the signal level is sufficient to ensure that each stage is
driven well into limiting, linear amplification serves little purpose
other than increasing the noise by more than necessary.

Bruce

ewkeh...@aol.com wrote:
Bruce, Thanks for your comments. It is my opinion that a dual mixer  
system
can be built including five counters for a material cost of less  
than $
200. The  computer interface would be USB. My challenge is the  
programming of
two u  processors and the software that need to be written for the  
computer.
How ever  there is so much expertise in this group to make it  
happen as a
joint effort, if  the interest is there. By integrating a dual  
channel counter


___
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.

[time-nuts] LORAN-C update....

[wa1zms]

Just noticed this.FYI
Not sure how this fits in with eLORAN efforts.

The Operating Status of LORAN-C

LORAN-C provides coverage for maritime navigation in U.S. coastal areas. It 
provides navigation, location, and timing services for both civil and military 
air, land and marine users. LORAN-C is approved as an en route supplemental air 
navigation system for both Instrument Flight Rule (IFR) and Visual Flight Rule 
(VFR) operations. The LORAN-C system serves the 48 continental states, their 
coastal areas, and parts of Alaska.

On February 26, 2009, the Office of Management and Budget (OMB) publicly 
announced the President's Fiscal Year 2010 Budget. In the section for the 
Department of Homeland Security, the budget supports the termination of 
outdated systems such as the terrestrial-based, long-range radionavigation 
(LOrAN-C) operated by the U.S. Coast Guard resulting in an offset of $36 
million in 2010 and $190 million over five years. For more information on the 
proposed FY2010 Budget, visit the OMB website under President's Budget.

The Coast Guard will continue to operate the current Loran C system through the 
end of FY2009 and is preparing detailed plans for implementing the FY2010 
Budget. 


___
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.

[time-nuts] Z3801A LED display...

[wa1zms]

FWIW...

I have one of my Z3801A running with an external LED display
that's based on one of the Dave Robinson, G4FRE PIC controllers.
His design reads the raw binary output from the internal GPS RX.

A mini-disc cam-corder was aimed at the display and caught
the leapsecond.

ie:
23:59:58
23:59:59
23:59:60
00:00:00
00:00:01

I'll try and snag a few seconds of video from the DVD around the event
if anybody is interested. Had WWV on in the background but was not mic'ed
very well so sound is low.

-Brian, WA1ZMS



___
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.

Re: [time-nuts] Close-in phase noise (long reply)

[wa1zms]

Luis-
Only beacuse I was more familiar with balanced doublers,
and felt that the x4 would need tougher filtering.

The balanced doublers also have much better conversion
efficiency, thus fewer gain stages. Or so I think.

Besides, I had drawers full of 1N5711 diodes,  toriods!

-Brian


 -- Original message from Luis Cupido cup...@mail.ua.pt: 
--


 Brian,
 
 Was there any particular reason to
 go from 5MHz to 20MHz in two steps ?
 couldn't be just one x4 stage followed by the filter
 (preferably xtal) ?
 
 Luis Cupido.
 ct1dmk.
 


___
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.

[time-nuts] Close-in phase noise question...more info...

[wa1zms]

First, thanks for the replies from all.


More info on the LO chain:

1) 5MHz Wenzel OCXO --Custom Osc for me.
2) MSA-1105 buffer MMIC and lumped LPF
3) 5MHz to 10MHz 1N5711 diode based doubler
4) MSA-1105 buffer and lumped LPF
5) 10MHz to 20MHz 1N5711 diode based doubler
6) 20MHz BPF
7) 20MHz drives sampling detector inside surplus Frequency
West PLL block to lock 1320MHz cavity oscillator.
8) 1320MHz drives Frequency West SRD multiplier to 6.6GHz.
9) 6.6GHz to 39.6GHz Milliwave diode multiplier/amp/filter
10) 39.6GHz to 79.2GHz in varactor doubler
11) 79.2GHz to 158.4GHz in varactor doubler
12) 158.4GHz into x4 sub-harmonic mixer

So my question was based on best close-in phase
noise in LO chain going from 5MHz to 20MHz.
My MSA-1105 MMICs may be running near or just
into compression and I may need to adjust the
design gain stack-up.

-Brian




___
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.

Re: [time-nuts] Close-in phase noise (long reply)

[wa1zms]

John-

The BPFs in the 5 to 20MHz chain are just 7-pole LC
filters with the goal of trying to keep any other
harmonics other than the desired at least -50dBc.
Xtal filters would be the better choice, no doubt.

The -50dBc level is clearly not the best
that one could get, but was enough for an earlier
240GHz project. I just used the same OCXOs and early
stages of multipliers to get the latest system running
on 630GHz.

In the 241GHz system, I ended up building a direct
frequency synthesizer to get 110MHz from a 10MHz
drive signal.  At the time, the Freq West PLL
blocks I used wanted a VHF signal to drive
the sampling detector to phase lock the L-band
cavity VCO. The original Freq West units used 5th OT
xtals for the commercial applications.

By later experimentation, I found that
the same sampling detector would also work with a
much lower frequency reference and still lock the
loop. The risk however is that the PLL might lock
on the wrong harmonic of the reference (i.e.: value of N)
or can have higher reference spur levels since the
PLL was designed assuming a VHF reference and not an
HF reference frequency. But this is not a commercial
design project, and I can live with a difficult alignment
procedure or initial power-up PLL lock troubles.

But all this aside, my efforts are currently aimed at
best close-in noise within the first 1KHz of BW around
the carrier.

The PLL bricks all seem to have several kHz of loop BW,
so my close-in noise going from 20MHz to 1320MHz should
be only slightly worse than 20Log(n), with n=66 in my case.
But I'm not ruling out the chance of 1/f noise (or similar)
showing up from the sampling detector or some other yet-to-be
determined source.

However my focus is currently on the 5MHz to 20MHz portion
of the LO chain and to be sure the gain stages are not
running near compression. I do still agree with your
earlier comment about getting the most from that portion
of the chain.

-Brian, WA1ZMS

-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of John Miles
Sent: Tuesday, December 16, 2008 7:53 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Close-in phase noise question...more info...


 More info on the LO chain:

 1) 5MHz Wenzel OCXO --Custom Osc for me.
 2) MSA-1105 buffer MMIC and lumped LPF
 3) 5MHz to 10MHz 1N5711 diode based doubler
 4) MSA-1105 buffer and lumped LPF
 5) 10MHz to 20MHz 1N5711 diode based doubler
 6) 20MHz BPF

What kind of BPF?  A really narrow crystal filter would be nice here.  (You
have basically reproduced the 8568A/B's 20 MHz reference section.)

 7) 20MHz drives sampling detector inside surplus Frequency
 West PLL block to lock 1320MHz cavity oscillator.

Sounds OK as long as the sampler loop's noise floor doesn't limit you.  I
haven't measured the in-band residual floor of any bricks but I'd be
surprised if an SRD multiplier wouldn't be quieter.

 8) 1320MHz drives Frequency West SRD multiplier to 6.6GHz.

If I wanted to get to several GHz with what's in my junk box right now, I
would do what you did to get to 20 MHz, BPF it with a multipole crystal
filter, and then use a few more multiplier stages to get somewhere between
100 MHz and 1 GHz, a la the 8662A reference section, depending on the choice
of the next stage.

That VHF drive signal would go into either an HP 33002A or 33004A SRD
multiplier, or one of the Picosecond NLTL multipliers (e.g.,
http://www.picosecond.com/product/product.asp?prod_id=109 ) I picked up in
their fire sale when they shut down their fab.

 9) 6.6GHz to 39.6GHz Milliwave diode multiplier/amp/filter
 10) 39.6GHz to 79.2GHz in varactor doubler
 11) 79.2GHz to 158.4GHz in varactor doubler
 12) 158.4GHz into x4 sub-harmonic mixer

AFAIK the rest of the chain is fine.  I'd focus on getting rid of the brick
PLL, or at least taking pains to make sure that it's not the problem, before
worrying about the MMICs in your early stages.

Remember that there's no point in optimizing the PN of any one stage much
below the input-referred residual noise of the following stage.  MMICs, in
saturation or not, are pretty quiet.  Quieter than sampler loops anyway.

-- john, KE5FX


___
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.


___
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.

[time-nuts] Close-in phase noise question...

[wa1zms]

Looking for comment here...

The background:
I'm working on a sub mm-wave LO chain for
a ham radio application. While chasing issues
of close-in phase (ie: within 1KHz of RF
carrier) by peeling the layers of the onion,
I'm starting to question the performance of
the MMICs that are used as buffers and amps
following my Wenzel reference OCXOs.

Question(s):
Should any MMIC be allowed to be driven
close to compression or into compression
when striving for best close-in noise?

I know and have seen the NF of a MMIC
degrade while in compression, but my
target right now is close-in noise rather
than broadband noise.

My design, in summary, takes 5MHz up to 630GHz
via several multipliers and PLL stages.

-Brian





___
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.

Re: [time-nuts] Close-in phase noise question...

[wa1zms]

John-

I do agree with you. The pain is in the early stages of the
LO chain.  Since I'm planning to use QRSS CW (that's very
slow speed Morse Code with very narrow demod bandwidths for
non-hams on this reflector who may not be familiar with QRSS),
the noise very close to the carrier become key.

A noisy carrier can't be detected very well on a waterfall
display if it too, looks like noise.

I have a several MSA-1105 MMICs in the chain to provide
isolation and give gain while multiplying the 5MHz signal
to 10MHz and then to 20MHz. The 20MHz acts as a reference
for a 1320MHz PLL. The 1320MHz then is multiplied several
more times on it's way to a sun-harmonic mixer for 630GHz.

I am wondering if the MSA-1105s could be causing more
close-in noise than I expected. The CW note sounds a
bit rough by ear.

The final 600GHz mixer that I'm using comes from some of
the mm-wave boys that work with NRAO.

But my LO noise requirements are a bit different than their
needs.


 

 

 -- Original message from John Miles jmi...@pop.net: 
--


 The painful part is probably the first few stages, if you are starting at 5
 MHz.  You probably want to do some HP 8662A-like tricks using crystal
 filters to shave off the broadband noise below 1 GHz, and maybe SAW filters
 above that.  This will do nothing for noise within 1 kHz, though... do you
 really need a clean signal that close to the carrier all the way up to 630
 GHz?
 
 The noise characteristics of the MMICs seems to depend a lot on the fab
 technology.  I can't seem to find my .PDF copy of it right now, but I have
 one paper on microwave regenerative dividers where the authors measured the
 residual PN of several contemporary parts driven to saturation.  At 4.5 GHz,
 the 10 dB/decade corner frequency wasn't reached until past 100 kHz for the
 Stanford Microdevices SGA-4186, which didn't speak well for the PN
 performance of SiGe HBT parts.  They showed -143 dBc/Hz at 1 kHz for that
 one.
 
 The GaAs HBT part (Mini-Circuits ERA-5SM) they tested was among the best
 (-156 dBc/Hz at 1 kHz).  Second-worst was an InGaP/GaAs HBT part (Stanford
 NGA-489) at about -153 dBc/Hz at 1 kHz.  Still much better than the SiGe
 part.
 
 My understanding is that the newer GALI-series parts from Mini-Circuits are
 InGaP HBT devices so they'd presumably perform about like the NGA-489.
 You'd want to measure them to make sure, though, if your app is that
 critical.
 
 Take a look at NRAO's recent publications, especially those associated with
 the ALMA array (many of which are on their site).  They're doing the real
 bleeding-edge work at sub-mm these days.
 
 -- john, KE5FX
 
  -Original Message-
  From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
  Behalf Of wa1...@att.net
  Sent: Monday, December 15, 2008 8:54 AM
  To: time-nuts@febo.com
  Subject: [time-nuts] Close-in phase noise question...
 
 
  Looking for comment here...
 
  The background:
  I'm working on a sub mm-wave LO chain for
  a ham radio application. While chasing issues
  of close-in phase (ie: within 1KHz of RF
  carrier) by peeling the layers of the onion,
  I'm starting to question the performance of
  the MMICs that are used as buffers and amps
  following my Wenzel reference OCXOs.
 
  Question(s):
  Should any MMIC be allowed to be driven
  close to compression or into compression
  when striving for best close-in noise?
 
  I know and have seen the NF of a MMIC
  degrade while in compression, but my
  target right now is close-in noise rather
  than broadband noise.
 
  My design, in summary, takes 5MHz up to 630GHz
  via several multipliers and PLL stages.
 
  -Brian
 
 
 
 
 
 ___
 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.






___
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.

Re: [time-nuts] Close-in phase noise question...

[wa1zms]

I would assume that the bleeding takes place
just after the first molecule has performed it's
dissecting task.
 

  -- Original message from J. L. Trantham, M. D. 
jlt...@worldnet.att.net: --


 I really enjoy reading the mail on this group, but I thought it was the
 'front molecule on the cutting edge'.
 
 Joe


___
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.

Re: [time-nuts] Close-in phase noise question...

[wa1zms]

Bruce-

OK... So, linear operation does therefore seem to be the preferred
way to operate these MMICs rather than operation into compression.
That's what I seem to be observing if only because my final RF
frequency is so high and RX bandwidth so low.

Having said that, if my frequency synthesis scheme involves a mixer
does the same effect of low frequency noise to phase noise conversion still
take place? After all, the mixer element is typically into compression
if it's a FET based mixer. I assume a diode mixer is more immune to
similar effects?

I'm trying to grow my intuitive understanding of the subtle sources of
noise. But I don't recall Maas giving much info on this topic in
his otherwise excellent text.

As always, thanks for your sagely advice.

-Brian


-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of Bruce Griffiths
Sent: Monday, December 15, 2008 5:00 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Close-in phase noise question...


wa1...@att.net wrote:
 Looking for comment here...

 The background:
 I'm working on a sub mm-wave LO chain for
 a ham radio application. While chasing issues
 of close-in phase (ie: within 1KHz of RF
 carrier) by peeling the layers of the onion,
 I'm starting to question the performance of
 the MMICs that are used as buffers and amps
 following my Wenzel reference OCXOs.

 Question(s):
 Should any MMIC be allowed to be driven
 close to compression or into compression
 when striving for best close-in noise?

 I know and have seen the NF of a MMIC
 degrade while in compression, but my
 target right now is close-in noise rather
 than broadband noise.

 My design, in summary, takes 5MHz up to 630GHz
 via several multipliers and PLL stages.

 -Brian

Brian

The increased nonlinearity when driven into compression will enhance the
conversion of low frequency noise to phase noise.

Bruce

___
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.


___
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.

Re: [time-nuts] Checking accuracy of Rubidium standards

[wa1zms]

This sounds to be a very similar method that my Tracor 895A uses.
Does that sound correct?

-Brian, WA1ZMS

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Neville Michie
Sent: Saturday, November 08, 2008 5:09 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Checking accuracy of Rubidium standards


Hi,
I have a plan which involves the dividing down of the 10MHz of a GPSDO
and a rubidium (LPRO) to about 1MHz or 100kHZ and applying them to a
XOR or D latch to get a PWM signal that can be averaged for a strip  
chart recorder or
12 bit analogue data logger. The DC output gives a range of 5 volts  
for one
microsecond or 10 microseconds phase difference and folds back if  
this difference is exceeded.
The data from the datalogger is in a format that a spreadsheet can use.
With time and phase measurements I wonder how hard it is to get Allen  
variance.
I realise the PWM method requires a low pass filter and this will  
prevent short period
variances from being calculated.
cheers, Neville Michie
and follow the instructions there.

___
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.

[time-nuts] Looking for HP5085A info...

[wa1zms]

Does anyone have a manual or at least a schematic for
an HP-5085A back-up power supply?

I searched the web and didn't find anything. That doesn't
mean it's there, just that I was unable to find it!

Thanks in advance,
-Brian, WA1ZMS


___
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.

Re: [time-nuts] Disciplining Rubidium

[wa1zms]

In talking to Charles Wenzel some years back, he mentioned what he called
the quartz-to-crud ratio.  i.e.: How much contamination you get while
making
a quartz crystal vs. the Q of the quartz blank itself.

It seems that through either luck/design or just demands of the industry
that
5MHz is the sweet spot for lowest close-in phase noise of an XO.

Other technologies may very well change that in future, but for best
close-in noise a 5MHz XO seems to be the best today.



-Brian, WA1ZMS

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of John Ackermann N8UR
Sent: Thursday, April 24, 2008 7:21 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Disciplining Rubidium


John Miles wrote:
 Phase noise generally gets better with the higher-frequency OCXOs, though.
 I think the best of all possible worlds would be a 5-MHz OCXO like the one
 you describe, being used to discipline a 10 MHz or higher-frequency part.

 -- john, KE5FX

I'm not sure about that -- at least, the Wenzel ULNs show better noise
at small offsets for the 5 MHz than the 10 MHz versions (though the
floor is the same).

___
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.


___
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.

Re: [time-nuts] Disciplining Rubidium

[wa1zms]

But doesn't it matter what your definition of short term really is?

I have some Wenzel OCXOs that hit 5E-13 for a 1 second tau. No Rb or Cs
or Z3801 that I have running get that good at 1 sec tau!  Over 10,000
is a different matter, however.


-Brian, WA1ZMS

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Tom Duckworth
Sent: Wednesday, April 23, 2008 6:13 PM
To: 'Discussion of precise time and frequency measurement'
Subject: Re: [time-nuts] Disciplining Rubidium


Antonio,

Absolutely! With a good XTAL you have parts in the 9th, short term. With a
XTAL controlled by a Rubidium, in the phase-lock feedback loop, you have
parts in the 12th, short term. With the Rubidium disciplined by the GPS,
with its on-board Rubidium/Cesium oscillators updated from the ground every
orbit, you have parts in the 14th, short term. In other words, your
XTAL/Rubidium/GPS has an effective short-term Allen variance equivalent to a
good Cesium; and better than a single Cesium, long term, for a lot less
money!

Tom
Tom Duckworth
510-886-1396

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of [EMAIL PROTECTED]
Sent: Wednesday, April 23, 2008 3:11 PM
To: time-nuts
Subject: [time-nuts] Disciplining Rubidium

Does it make any sense GPS disciplining a rubidium oscillator?
In such a case we have a chain made of
GPS - Rubidium - XTAL
as opposed to the simpler case of
GPS - XTAL
(assume that XTALs are of the same quality, and so the control loops).
Does the addition of Rb in the middle of the chain add
any real advantages?

Antonio I8IOV



___
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.


___
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.


___
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.

Re: [time-nuts] (no subject)

[wa1zms]

David-

Although you are likely OK being at VHF, please keep in mind that some
of the low-freq clock type oscillators have poor phase noise when
it comes to trying to copy signals like CW.

A good easy test is to listen to one of the oscillators on a good
general coverage RX and see how good the CW note sounds. If you're
happy with it, then its use as a LO for a transverter is likely OK.

Also remember that modes like PSK31, WSJT, etc. will want slightly better
LO phase noise to function well.

But the CW listening test is a simple easy place to start.

73,
Brian, WA1ZMS/4


 -- Original message from David Hilton-Jones [EMAIL PROTECTED]: 
--


 I want to generate sine wave signals at 42MHz and 116MHz for use with VHF 
 transverters. A simple tcxo isn't stable enough. I'm looking for simple/cheap 
 solutions and I'd appreciate any comments.
 1) I have a stable reference at 10MHz available
 2) Reflock is overkill
 3) I guess a G8ACE type ocxo would do for 116MHz.
 4) I read with interest about FlashCrystal units, but they now seem 
 unavailable.
 5) On e-bay international I see McCoy/Vectron ocxo at 48.MHz (can't 
 remember 
 exact frequency) - that might do for my 42MHz requirement , with some mods to 
 the rest of the transverter. Any UK source?
 6) I don't know much about DDS systems.
 
 Any comments much appreciated.
 
 David
 
 ___
 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.



___
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.

Re: [time-nuts] TAC32 Z3801A

[wa1zms]

Rick-

I'd be willing to loan you a Z3801A if you'd like, to help you write some
software.

-Brian, WA1ZMS/4




 

 

 -- Original message from Rick Hambly (W2GPS) [EMAIL 
PROTECTED]: --


 John,
 
 If I had a Z3801A I might be inclined to add support for it to Tac32 but I
 do not have one.
 
 Rick
 W2GPS
 AMSAT LM2232
  
 -Original Message-
 From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
 Behalf Of John Ackermann N8UR
 Sent: Friday, April 04, 2008 1:03 PM
 To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement
 Subject: Re: [time-nuts] TAC32  Z3801A
 
 The Z3801A doesn't talk native Motorola -- it has its own set of 
 commands based on the SCPI protocol.  So I don't think you'll have any 
 luck using the Motorola-based programs to talk to it.
 
 John
 
 
 Bill Janssen wrote:
  I was trying to get TAC32 to talk to my Z3801A, and no luck. I have
  HP SATSTAT working OK but not TAC32 (or SynTac). SATSTAT uses COM 1, at 
  19200,7 bits and odd parity. Incidentally I modified the Z3801A to be 
  RS232, if that makes a difference
  
  How do I convince TAC32 to connect to my Z3801A
  
  Any help appreciated
  Bill K7NOM
  
  
  ___
  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.
  
  
 
 
 ___
 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.
 
 
 ___
 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.



___
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.

Re: [time-nuts] Temex rubidium

[wa1zms]

Antonio-

You have a good point. In my case, the varactor voltage as read by
the A to D shows EF which is very close to the FF max indicated
in the manual.  If the temperature of the unit is warm or hot the
unit will lock. But if at room temp or cold the unit will never
reach a locked condition.

I have adjusted the freq trim settings both digital and analog
and just cannot trim the unit any more. Over the past several years
the unit has needed trim in one direction and so it is not
unexpected.

This is a very compact unit and I'm hoping to find a schematic
before I open it. Otherwise, I'll be drawing my own.

Thanks.

-Brian, WA1ZMS/4

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of [EMAIL PROTECTED]
Sent: Sunday, February 03, 2008 5:42 PM
To: time-nuts
Subject: Re: [time-nuts] Temex rubidium


I would report my experience with an EFRATOM LPRO with a similar problem,
maybe this could help.
The sweept frequency was always below 10 MHz, so missing the opportunity to
lock.
The sweept VCXO control voltage at the monitor pin was correct, but at the
varactor it was too low. The problem was in a faulty (leaking) SMD ceramic
capacitor
on the control voltage line to the varactor. Once replaced the capacitor,
the LPRO
rose again.
So, I would suggest you checking the voltage at the varactor.
Antonio I8IOV


 I have a Temex LPFRS rubidium standard that from
 all indications appears to have an internal xtal osc
 that has drifted beyond what the control loop can
 correct for.

 Before I take the unit apart to try and manually trim
 the XO, does anyone has an internal schematic for it?
 (I have the operation/user manual already.)

 Has anyone else done this type of repair on such a model?

 Thanks in advance,
 -Brian, WA1ZMS/4



___
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.


___
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.