[time-nuts] Re: OCXO McCoy Electronics OSC92-51B

[Orin Eman]

It was used in the HP 8566B Spectrum Analyzer for a while at least.  So
whatever the 8566B specified for its OCXO would be a minimum.

I have a dead* one here from my 8566B.  The pins are wired to a connector
with the following colors:

1,2) Black
3) Red
4) Purple
5) Orange
6) Black

No EFC to my knowledge.

From the 8566B service manual, and assuming that the wire numbering matches
the color codes, then:

Red: +20V switched, i.e. osc power supply.
Black: Ground.
Purple: HOVC i.e high oven cold (where high is 20V or so).
Orange: +22V oven supply.

The Corning branded version of the OSC92-51B is still available NOS.  I put
one in my 8566B.  I got a few spares too.  Ignore the ridiculous ebay
prices if you want one and try Quest components who may still have a few
(though you'll pay their line item minimum if you only want one).

* It was > 70 Hz out and could not be adjusted into spec.


On Tue, Apr 13, 2021 at 3:58 PM Bob kb8tq  wrote:

> Hi
>
> Since this is a part that Ovenaire made for HP, probably the best way to
> work out what’s what is to find the equipment that it went into. Best guess
> is that would be an item that shows up in the 1985 ~ 2005 HP catalogs.
>
> ( = OSC92 is an Ovenaire part number that was carried on after McCoy
> folded Ovenaire into the “empire”). That makes it a > 25 year old spec.
>
> Rough guess at the specs:
>
> 5x10^-8 over 0 to 70C
> -150 dbc/Hz at 10 KHz offset
> 10 dbm +/- 3 db
> 10W power at turn on.
>
> With the fine adjust it may or may not have an EFC. There are enough pins
> for
> it to have one.
>
> Pinout looking at it with the SMA “up” and numbering from left to right:
>
> 1) V- / return / ground
> 2) Case
> 3) B+
> 4) ???
> 5) ???
> 6) ground
>
> Bob
>
> > On Apr 13, 2021, at 3:17 PM, Juerg Koegel  wrote:
> >
> > I am looking for data (PinOut, Power, Stability, Phase Noise, EFC )  for
> the 10MHz OCXO McCoy Electronics OSC92-51B.
> > Thanks for all information.
> >
> > Juerg
> > ___
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[time-nuts] FPGA card with two 10MHZ inputs, and two 1 PPS inputs?

[Anders Löwinger]

Hi!


Is there anyone that can recommend a Xilinx FPGA PCIe card with a XCVU9P 
in a standard PCIe formfactor, which can receive two 10MHz and two 1PPS 
(from two different frequency sources).


The 10MHz needs to be connected to a Xilinx Global clock register, the 
1PPS is fine with a standard GPIO.



During development we have used a Xilinx VCU118 card with a XCVU9P, but 
the non-PCIe formfactor makes it hard to find a chassis that does not 
need modifications.


I've googled for a couple of hours, but did not find anything definitive.


--
MVH/Regards
Anders Löwinger, Abundo AB, 072-206 0322
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[time-nuts] Re: OCXO McCoy Electronics OSC92-51B

[DM]

On a hunch, I searched for the other part number on the nameplate (0960-0477) 
in one of the military stock reseller's database and found that the only end 
item that this oscillator was used in was the AN/FPS-115 PAVE PAWS (Precision 
Acquisition Vehicle Entry - Phased Array Warning System) radar system, 
developed in the 1980s for the US Navy. I searched for any technical 
information on this system and came up empty. Maybe someone else can do better 
than I did. 
The national stock number for the oscillator is 5955-01-086-8122, and is 
described as a NON-CRYSTAL Controlled oscillator!! 

Good luck in your search, 

DaveM 

From: "Bob kb8tq"  
To: "Discussion of precise time and frequency measurement" 
 
Sent: Tuesday, April 13, 2021 5:58:15 PM 
Subject: [time-nuts] Re: OCXO McCoy Electronics OSC92-51B 

Hi 

Since this is a part that Ovenaire made for HP, probably the best way to 
work out what’s what is to find the equipment that it went into. Best guess 
is that would be an item that shows up in the 1985 ~ 2005 HP catalogs. 

( = OSC92 is an Ovenaire part number that was carried on after McCoy 
folded Ovenaire into the “empire”). That makes it a > 25 year old spec. 

Rough guess at the specs: 

5x10^-8 over 0 to 70C 
-150 dbc/Hz at 10 KHz offset 
10 dbm +/- 3 db 
10W power at turn on. 

With the fine adjust it may or may not have an EFC. There are enough pins for 
it to have one. 

Pinout looking at it with the SMA “up” and numbering from left to right: 

1) V- / return / ground 
2) Case 
3) B+ 
4) ??? 
5) ??? 
6) ground 

Bob 

> On Apr 13, 2021, at 3:17 PM, Juerg Koegel  wrote: 
> 
> I am looking for data (PinOut, Power, Stability, Phase Noise, EFC ) for the 
> 10MHz OCXO McCoy Electronics OSC92-51B. 
> Thanks for all information. 
> 
> Juerg 
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[time-nuts] Re: OCXO McCoy Electronics OSC92-51B

[Bob kb8tq]

Hi

Since this is a part that Ovenaire made for HP, probably the best way to 
work out what’s what is to find the equipment that it went into. Best guess
is that would be an item that shows up in the 1985 ~ 2005 HP catalogs. 

( = OSC92 is an Ovenaire part number that was carried on after McCoy 
folded Ovenaire into the “empire”). That makes it a > 25 year old spec. 

Rough guess at the specs:

5x10^-8 over 0 to 70C
-150 dbc/Hz at 10 KHz offset
10 dbm +/- 3 db
10W power at turn on. 

With the fine adjust it may or may not have an EFC. There are enough pins for 
it to have one. 

Pinout looking at it with the SMA “up” and numbering from left to right:

1) V- / return / ground
2) Case
3) B+
4) ???
5) ???
6) ground

Bob

> On Apr 13, 2021, at 3:17 PM, Juerg Koegel  wrote:
> 
> I am looking for data (PinOut, Power, Stability, Phase Noise, EFC )  for the 
> 10MHz OCXO McCoy Electronics OSC92-51B.
> Thanks for all information.
> 
> Juerg
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[time-nuts] Re: Replacement of Windows NTP server with Linux

[Kevin Schuchmann via time-nuts]

Russ,
  You could have also just run gpedit.msc (group policy editor) to turn off the 
updates/reboots in windows 10.
It comes standard on pro but can be added to home also I believe.

Kevin




‐‐‐ Original Message ‐‐‐
On Tuesday, April 13, 2021 9:56 AM, Russ Ramirez  wrote:

> I have been running a Windows PC with Lady Heather and Meinberg NTP monitor
> for 6-7 years now. One very annoying problem with Windows 10 has been the
> forced updates and reboots knocking my headless configuration on it's arse.
>
> So I have been experimenting with various Linux options, first with RPi 4
> with a compiled version of LH, and now with Ubuntu Server 20.04 using
> chrony, gpsd and of course the attached GPS device (NMEA for now, but being
> replaced with the Tbolt attached to the Win 10 PC).
>
> All seems to be working fine, the chronyc monitoring looks good and a run
> of w32tm /stripchart /computer: looks good compared to the Win 10 peer.
>
> I'll next be wiring-up PPS for the first time for the next round of tests.
>
> For you X experts out there, is there anything I need to watch out for? TIA
>
> Russ
> K0WFS
>
> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an 
> email to time-nuts-le...@lists.febo.com
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[time-nuts] OCXO McCoy Electronics OSC92-51B

[Juerg Koegel]

I am looking for data (PinOut, Power, Stability, Phase Noise, EFC )  for 
the 10MHz OCXO McCoy Electronics OSC92-51B.

Thanks for all information.

Juerg
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[time-nuts] Re: Replacement of Windows NTP server with Linux

[Tim Shoppa]

Ubuntu server is great - I’ve been supporting applications on Ubuntu for
over 10 years now and it is easy to maintain and update.

Set Ubuntu up absolutely minimally - no packages installed unless
absolutely necessary. Certainly no X11 or GUI desktop. This way the number
of security updates will be lowest.

Instead of chrony , I use ntpd because of 30+ years experience under my
belt with that. (As well as experience customizing I/O for esoteric
refclocks like WWV audio).

Tim N3QE

On Tuesday, April 13, 2021, Russ Ramirez  wrote:

> I have been running a Windows PC with Lady Heather and Meinberg NTP monitor
> for 6-7 years now. One very annoying problem with Windows 10 has been the
> forced updates and reboots knocking my headless configuration on it's arse.
>
> So I have been experimenting with various Linux options, first with RPi 4
> with a compiled version of LH, and now with Ubuntu Server 20.04 using
> chrony, gpsd and of course the attached GPS device (NMEA for now, but being
> replaced with the Tbolt attached to the Win 10 PC).
>
> All seems to be working fine, the chronyc monitoring looks good and a run
> of w32tm /stripchart /computer: looks good compared to the Win 10 peer.
>
> I'll next be wiring-up PPS for the first time for the next round of tests.
>
> For you X experts out there, is there anything I need to watch out for? TIA
>
> Russ
> K0WFS
> ___
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> an email to time-nuts-le...@lists.febo.com
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>
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[time-nuts] Replacement of Windows NTP server with Linux

[Russ Ramirez]

I have been running a Windows PC with Lady Heather and Meinberg NTP monitor
for 6-7 years now. One very annoying problem with Windows 10 has been the
forced updates and reboots knocking my headless configuration on it's arse.

So I have been experimenting with various Linux options, first with RPi 4
with a compiled version of LH, and now with Ubuntu Server 20.04 using
chrony, gpsd and of course the attached GPS device (NMEA for now, but being
replaced with the Tbolt attached to the Win 10 PC).

All seems to be working fine, the chronyc monitoring looks good and a run
of w32tm /stripchart /computer: looks good compared to the Win 10 peer.

I'll next be wiring-up PPS for the first time for the next round of tests.

For you X experts out there, is there anything I need to watch out for? TIA

Russ
K0WFS
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[time-nuts] Re: Video of early Cesium clock development

[paul swed]

Tom
I remember the pictures of the unit. But perhaps did not realize that you
actually purchased or own the unit? Now that would be one heck of a job to
clean up. Would guess the C's are very very long gone. Although the
video sent was interesting to see how they just dumped the Cs capsule in.
It looked like a plunger mechanism to break the capsule. Maybe a
solenoid hit the plunger.
Anyhow like Masers maybe it could be revived. Time-nuts tend to do the
impossible.
Regards
Paul
WB8TSL

On Tue, Apr 13, 2021 at 9:45 AM Tom Van Baak  wrote:

> Jerry, thanks for posting that National Co Atomichron video link. And,
> Tim, thanks for posting the Smithsonian link.
>
> ---
>
> The first *laboratory* cesium standard was made by Louis Essen. Much has
> been written about this. My own pilgrimage:
>
>http://leapsecond.com/museum/essen/
>
> The first *commercial* cesium standard was the Atomichron by the
> National Company. A short article here:
>
>
> https://www.rfcafe.com/references/radio-news/atomichron-worlds-most-accurate-clock-january-1957-radio-television-news.htm
>
> About 50 of these early cesium clocks were made. Several are known to
> still exist: one owned by the Smithsonian as Tim noted, one at the NAWCC
> museum, and at least two in private hands. Some photos of the one I
> found on eBay are here:
>
>http://leapsecond.com/museum/nc2001/
>
> To get a feel for the size of this beast, here is a comparison of the
> Atomichron beam tube with a 5060 / 5061 / 5071 beam tube:
>
>http://leapsecond.com/museum/nc2001/IMG_6441-600x800.jpg
>
> This photo is also attached (an excuse to test normal vs. digest mode
> photo handling). It's also featured here:
>
>https://insidegnss.com/time-is-relative-position-absolute/
>
> ---
>
> If you are old enough to remember the vacuum tube and "atoms for peace"
> era you will appreciate the brilliant name choice for "Atomichron". A
> detailed Atomichron article by Paul Forman:
>
> https://ieee-uffc.org/about-us/history/uffc-s-history/atomichron/
>
> One interesting anecdote in the ieee article is Jerrold Zacharias and
> his "Fallotron", the original concept for what we now know as a Cesium
> fountain. And to wrap up this history of atomic clocks posting, here's a
> classic, including cesium and H-maser photos, by Norman Ramsey:
>
>https://nvlpubs.nist.gov/nistpubs/jres/088/jresv88n5p301_A1b.pdf
>
> /tvb
>
>
> On 4/12/2021 11:45 AM, Tim Shoppa wrote:
> > For those interested in the National Company’s cesium clocks, you can
> > google “Atomichron” (their brand name) or check out this Smithsonian
> > archive: https://sova.si.edu/record/NMAH.AC.0547
> > 
> >
> > Tim N3QE
> >
> > On Monday, April 12, 2021, Jerry Steinback via time-nuts <
> > time-nuts@lists.febo.com> wrote:
> >
> >> While munging around on Youtube, this short filmstrip popped up; it
> >> appears to be one of those short fillers for movie theater audiences.
> The
> >> first four minutes might be interesting to members of the group.
> >>  https://www.youtube.com/watch?v=NoDElB6HMCg
> >>
> >> Compared to any Cesium standard in the past couple(?) of decades it
> >> reminds me of the old Stan Freberg commercial for Contadina tomato
> paste:
> >> ''Who put eight great tomatoes in that little bitty can?''
> >> Jerry
> >> ___
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>
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