> $ sudo ldattach -d -s 9600 -n -8 -1 pps /dev/ttyUSB0
I assume you realize that PPS over USB isn't going to work well. (at least
by time-nuts standards)
There is also the opportunity for hanging-bridge type quirks.
--
These are my opinions. I hate spam.
Hi,
I started going through the docs and got a bit confused regarding
[ldattach] for creating a PPS source.
http://www.manualpages.de/OpenBSD/OpenBSD-5.0/man8/ldattach.8.html
port2 output would have been perfect to use, but ldattach doesn't have a
discipline for this binary format.
I was
>>> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom
>>> Van Baak
>>> Sent: Tuesday, September 29, 2015 1:41 AM
>>> To: Discussion of precise time and frequency measurement
>>> Subject: Re: [time-nuts] Z3805A firmware?
>&
On 09/30/2015 11:16 AM, David Gravereaux wrote:
> Hi,
>
> I started going through the docs and got a bit confused regarding
> [ldattach] for creating a PPS source.
>
> http://www.manualpages.de/OpenBSD/OpenBSD-5.0/man8/ldattach.8.html
^-- Oops, old man page not current to the 3.19.x kernel I'm
On 09/28/2015 10:40 PM, Tom Van Baak wrote:
...
> 2) A decades-old surplus eBay GPSDO like this is good to absolutely stunning
> for home and casual lab use. But I would avoid using them for embedded,
> serious, professional, or life-safety applications. Can you tell us more what
> your
> Good detective work. Yes, it sounds like a GPS 2^10 = 1024 WNRO issue, but
> no one else has ever reported this AFAIK, so it's very curious.
I've seen it on a Z3801A. I'm pretty sure I mentioned it here. That was
several years ago.
I think I had to set the time after power up but before it
On 09/29/2015 12:28 AM, Hal Murray wrote:
>
>> Good detective work. Yes, it sounds like a GPS 2^10 = 1024 WNRO issue, but
>> no one else has ever reported this AFAIK, so it's very curious.
>
> I've seen it on a Z3801A. I'm pretty sure I mentioned it here. That was
> several years ago.
>
> I
Hi,
I've had my unit off and in the closet for quite some time, then played
around with it yesterday. :GPS:INIT:DATE wasn't taking 2015,09,28 and
kept returning E-222 "data out of range" and was stuck in 1996. A few
power cycles and it got to 2007. A few more power cycles and finally it
got it
Hi,
I've got a Z3805A that I bought off ebay a couple of
years ago, and it recently started going deaf, beginning
with an apparent loss of sensitivity leading to holdovers,
and more recently, receiver errors reported in the system
status.
I have the Z3805A, a thunderbolt, and one of the
The model number is that of an Oncore VP. It is easy to remove the receiver
from the unit for testing independently. That might be worth a try. Maybe
reseating it may help if there is any continuity problem on the pins.
Unfortunately you will probably need another VP to replace a dead one.
Brief update:
This receiver (whatever it is) refuses to forget 1995 despite un-powering,
etc. I will learn to live with it, I think.
It was sold to me as a Z3801A updated to 58503A.
However:
1. The main board is labeled Z3805A (Not Z3801A) as are some of the chips.
2. It has only one 10
Hi
There’s a lot of commonality between the HP Z38xx designs up through the 3812.
They are by no means identical, but as you have seen, they are not terribly
different either.
Welcome to the wonderful world of China Surplus Inc.
It would not really surprise me to find that somebody simply
On 3 Dec 2014 02:08, James Robbins jsrobb...@earthlink.net wrote:
Brief update:
This receiver (whatever it is) refuses to forget 1995 despite
un-powering, etc. I will learn to live with it, I think.
You could report it to the seller as a fault. He must have quite a bit of
experience on
On 2014-12-02 19:46, Dr. David Kirkby (Kirkby Microwave Ltd) wrote:
On 3 Dec 2014 02:08, James Robbins jsrobb...@earthlink.net wrote:
Another option would be to hack the ntp software so it gives out a correct
date, assuming that you can determine what the
It was sold to me as a Z3801A
I've acquired a Z3805A converted to a 58503A which, notwithstanding tracking,
seems to believe that it is 17 March 1995. I believe this is the famous
1024 week issue. Does anyone know how to spring the unit from it's
historical bonds and get it to read the current date. I have tried commands
jsrobb...@earthlink.net said:
I have tried commands (via GPSCon) to do a factory reset and to enter the
date manually, but without success.
You may have to power it off so it forgets the date before it will take the
date from the serial port.
--
These are my opinions. I hate spam.
Hi
The unit will do just fine as a frequency / pps standard with the date error.
I believe the answer is a re-flash of the firmware in the GPS module. The first
step there is to figure out which module you have. If it’s a Motorola you may
be in luck. If it’s a Furono, you may be out of luck.
Hi:
I opened up my Z3805A and after looking at the bottom of the main board think
it's already jumpered for RS-232.
See the bottom photo at: http://www.prc68.com/I/Z3805A.html#DB-25 near the
DB-25 connector.
There's only 3 zero Ohm jumpers and none of them are where the Z3801 jumpers
were.
Hi, I have two Z3805A's that I believe came from the same source as yours.
They both have RS-232 outputs.
Best
Regards
Mark Spencer
Message: 6
Date: Mon, 22 Apr 2013 15:26:14 -0700
From: Brooke Clarke bro...@pacific.net
To: time-nuts@febo.com
Subject: [time-nuts] Z3805A Stock RS-232
Hi:
I'm trying to learn more about the HP Z3805A GPSDO.
http://www.prc68.com/I/Z3805A.html
It has an OCXO that I haven't seen before with a paper sticker with it's p/n:
3505A09422
The A normally means made in America.
Does anyone know more about it?
http://www.prc68.com/I/Z3805A.html#OCXO
On 4/18/2013 5:41 PM, Brooke Clarke wrote:
It has an OCXO that I haven't seen before with a paper sticker with it's
p/n: 3505A09422
The A normally means made in America.
It's a double oven HP 10811A, you're looking at the serial number sticker.
___
Hi Brooke,
On 04/18/2013 11:41 PM, Brooke Clarke wrote:
Hi:
I'm trying to learn more about the HP Z3805A GPSDO.
http://www.prc68.com/I/Z3805A.html
It has an OCXO that I haven't seen before with a paper sticker with it's
p/n: 3505A09422
The A normally means made in America.
Does anyone know
It looks more like a HP serial number.
Tom
- Original Message -
From: Brooke Clarke bro...@pacific.net
To: time-nuts@febo.com
Sent: Thursday, April 18, 2013 5:41 PM
Subject: [time-nuts] Z3805A OCXO p/n 3505A09422?
Hi:
I'm trying to learn more about the HP Z3805A GPSDO.
http
: Thursday, April 18, 2013 4:41 PM
To: time-nuts@febo.com
Subject: [time-nuts] Z3805A OCXO p/n 3505A09422?
Hi:
I'm trying to learn more about the HP Z3805A GPSDO.
http://www.prc68.com/I/Z3805A.html
It has an OCXO that I haven't seen before with a paper sticker with it's
p/n: 3505A09422 The A normally
On 18/04/13 22:41, Brooke Clarke wrote:
Hi:
I'm trying to learn more about the HP Z3805A GPSDO.
http://www.prc68.com/I/Z3805A.html
It has an OCXO that I haven't seen before with a paper sticker with it's
p/n: 3505A09422
The A normally means made in America.
Does anyone know more about it?
Brooke wrote:
I'm trying to learn more about the HP Z3805A GPSDO.
http://www.prc68.com/I/Z3805A.html
It has an OCXO that I haven't seen before with a paper sticker with
it's p/n: 3505A09422
The A normally means made in America.
Check the output on a spectrum analyzer for 5 MHz content.
I have two of these units and am quite pleased with them. Other than an app
note indicating that they are leap second compliant I've never seen any
documentation re the Z3805.
Sent from my iPad
___
time-nuts mailing list -- time-nuts@febo.com
To
Yes, indeed, I've got one with a 10811 and one with a symmetricom 5 MHz
oscillator with doubler.
Volker
Am 19.04.2013 01:15, schrieb Charles P. Steinmetz:
Check the output on a spectrum analyzer for 5 MHz content. I've seen
several internet-sourced Z3805As that were explicitly claimed to
Mark wrote:
For the first 6 hours PU stayed at 432us, then it dropped sharply to
5.6us and then slowly climbed to 18us.
Doesn't seem right to me.
Nothing it does in the first 6 hours has anything to do with
anything. (1) The oscillator will be swinging around wildly
(comparatively
Many thanks,
mark
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf
Of Charles P. Steinmetz
Sent: Wednesday, 17 April 2013 4:03 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Z3805A high value PU
Mark
I have dumped the 4 flash ROMS from my latest Z3805A but I can't make head nor
tail of the contents. I am thinking the flash are interleaved.
http://www.vk2hmc.net/blog/wp-content/uploads/2013/04/z3805-flash.rar
I can't see any strings that make sense like the Z3801A flash.
On Wed, Apr 17, 2013 at 08:31:49AM +, Mark C. Stephens wrote:
I have dumped the 4 flash ROMS from my latest Z3805A but
I can't make head nor tail of the contents.
I am thinking the flash are interleaved.
Interleaving makes sense for performance reasons and
usually happens at bit or byte
2013 12:43 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Z3805A flash dump.
On Wed, Apr 17, 2013 at 08:31:49AM +, Mark C. Stephens wrote:
I have dumped the 4 flash ROMS from my latest Z3805A but I can't make
head nor tail of the contents.
I am
of the result.
/tvb
- Original Message -
From: Mark C. Stephens ma...@non-stop.com.au
To: time-nuts@febo.com
Sent: Wednesday, April 17, 2013 1:31 AM
Subject: [time-nuts] Z3805A flash dump.
I have dumped the 4 flash ROMS from my latest Z3805A but I can't make head nor
tail of the contents. I am
In message AA42DD206D5541258C6A474D42B3C0F1@pc52, Tom Van Baak writes:
After you fix that, then combining low/high bytes will give you
what you want. See http://leapsecond.com/museum/z3801a/eeprom.htm
for an example of the result.
/tvb
If anybody feels like disassembling the code, I have
://leapsecond.com/museum/z3801a/eeprom.htm for an example of the result.
/tvb
- Original Message -
From: Mark C. Stephens ma...@non-stop.com.au
To: time-nuts@febo.com
Sent: Wednesday, April 17, 2013 1:31 AM
Subject: [time-nuts] Z3805A flash dump.
I have dumped the 4 flash ROMS from my latest Z3805A
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Herbert Poetzl
Sent: Thursday, 18 April 2013 12:43 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Z3805A flash dump.
On Wed, Apr 17, 2013 at 08:31:49AM
Of Tom Van Baak
Sent: Thursday, 18 April 2013 2:21 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Z3805A flash dump.
I suspect your reader is not configured correctly. For example, look at the
first 80 bytes of each BIN file; they should not be so identical.
After you fix
On Wed, 17 Apr 2013 08:26:08 +, Mark C. Stephens wrote:
On a more serious note, I have rack mounted both clocks with UPS power
and they shall not be disturbed.
http://www.vk2hmc.net/blog/?p=86
Many thanks,
Is it wise to install an unregulated fan inside the 3805 housing , so
close
: Thursday, 18 April 2013 4:32 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Z3805A high value PU
On Wed, 17 Apr 2013 08:26:08 +, Mark C. Stephens wrote:
On a more serious note, I have rack mounted both clocks with UPS power
and they shall not be disturbed.
http://www.vk2hmc.net/blog
Dear Fellows,
I recently purchased a pair of Z3805A off eBay seller tommy_chou.
I have fired them up with a MaxRad 26db timing antenna attached to each.
The antennae have a clear view of most of the sky.
The receivers are having no problems seeing enough satellites.
The problem I am seeing on
Mark wrote:
I recently purchased a pair of Z3805A
The problem I am seeing on both is the predicted uncertainty is high
compared to other receivers I have seen.
I am experiencing a PU of ~8us for the first and ~24us for the second.
My questions are,
What could be causing such bad figures?
of precise time and frequency measurement
Subject: Re: [time-nuts] Z3805A high value PU
Mark wrote:
I recently purchased a pair of Z3805A
The problem I am seeing on both is the predicted uncertainty is high
compared to other receivers I have seen.
I am experiencing a PU of ~8us for the first
On 4/16/13 8:28 PM, Mark C. Stephens wrote:
Actually, before I plugged the GPS antenna into the second unit, I checked out
where it last called home:
LAT N 36:01:05.225
LON E 128:41:48.761
HGT+1214.14 m (MSL)
Mt Palgong, according to Google Earth
Lots of transmitter towers up
I wanted to have a look at what the Z3805A puts out on Port 2.
I can see the LEDS flickering on the BOB so its saying something.
I connected up a terminal program set to 96008N1 and it seems there is nothing.
So I plugged the cable into port one to check the settings:
scpi syst:comm:ser2:pace?
On Thu, Apr 04, 2013 at 02:32:09PM +, Mark C. Stephens wrote:
I wanted to have a look at what the Z3805A puts out on Port 2.
I can see the LEDS flickering on the BOB so its saying something.
I connected up a terminal program set to 96008N1 and it seems there is
nothing.
So I plugged the
On 4/4/13 7:52 AM, Herbert Poetzl wrote:
On Thu, Apr 04, 2013 at 02:32:09PM +, Mark C. Stephens wrote:
I wanted to have a look at what the Z3805A puts out on Port 2.
I can see the LEDS flickering on the BOB so its saying something.
I connected up a terminal program set to 96008N1 and it
might mean locked to
GPS.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Jim Lux
Sent: Thursday, April 04, 2013 11:29 AM
To: time-nuts@febo.com
Subject: Re: [time-nuts] Z3805A Port 2.
On 4/4/13 7:52 AM, Herbert Poetzl wrote:
On Thu
On Thu, Apr 04, 2013 at 08:28:58AM -0700, Jim Lux wrote:
On 4/4/13 7:52 AM, Herbert Poetzl wrote:
On Thu, Apr 04, 2013 at 02:32:09PM +, Mark C. Stephens wrote:
I wanted to have a look at what the Z3805A puts out on Port 2.
I can see the LEDS flickering on the BOB so its saying something.
1 3 0 9 4 1 4 2 8 4 4 = 1309412844
I can see its transmitting the even second time but what format
is this and how can I use it?
$ date +%s # unix time (seconds since Jan, 1st, 1970)
1365086814
so, my guess is, it is seconds since some point in
time in decimal.
$ date
On Thu, Apr 04, 2013 at 02:54:09PM -0400, Paul wrote:
1 3 0 9 4 1 4 2 8 4 4 = 1309412844
I can see its transmitting the even second time but what format
is this and how can I use it?
$ date +%s # unix time (seconds since Jan, 1st, 1970)
1365086814
so, my guess is, it is
: [time-nuts] Z3805A/58503A time receiver : 2 questions
If your unit is exactly like that on ebay 251226027893, it has a 10 MHz HP
oscillator in a double oven, and it's absolutely sure that it's got a 6 channel
receiver.
I should have read before, sorry.
I'm still not sure about your antenna
Envoyé le : Jeudi 28 février 2013 2h12
Objet : Re: [time-nuts] Z3805A/58503A time receiver : 2 questions
If your unit is exactly like that on ebay 251226027893, it has a 10 MHz HP
oscillator in a double oven, and it's absolutely sure that it's got a 6 channel
receiver.
I should have read before
Reference
for the 5534B but I wanted to check its frequency first !)
De : Volker Esperail...@t-online.de
À : time-nuts@febo.com
Envoyé le : Jeudi 28 février 2013 2h12
Objet : Re: [time-nuts] Z3805A/58503A time receiver : 2 questions
If your unit
Hello,
This is my first message here although I read this list for a few weeks.
I bought a Z3805A/58503A frequency receiver and I didn't notice on the
pictures that the model number was not written on the front panel. It's not
important but is there a reason for that, if you know ?
The item
Hello Claude,
that gap is a classic crystal jump. It could be caused by the crystal
changing frequency by itself, or by being hit with e.g. gamma particles etc.
Could also have been instigated by vibration or shock to the unit.
You should be seeing 6+ sats at all times though, your plot
Hi Claude!
Said says, you should see 6+ sats, I guess he means _at_least_ six. I'm
almost sure, you've got a 6 channel receiver, so you naturally cant't
get more than 6 sats at a time.
There are some different models of the Z3805A out there, though they're
all named the same. I've got two
I just calculated the frequency offset. I count 5 crosses, while jumping
down to 200 ns, I guess, 1 cross equals 10 min? So let's say the jump
lasts 60 min (= T jump). When we want to calculate the frequency offset
out of a phase jump, we have to differentiate the phase and we should
achieve
If your unit is exactly like that on ebay 251226027893, it has a 10 MHz
HP oscillator in a double oven, and it's absolutely sure that it's got a
6 channel receiver.
I should have read before, sorry.
I'm still not sure about your antenna, is it a Garmin? Well, it's most
likely an active
Hi the Timing-Gang,
I got very recently a Z3805A GPSDO six channels coming from China from
one of the most serious Chinese shop on The Bay ... :-D :-D :-D
It's a six channels GPS unit and I would like to upgrade it by myself
with a 12 channels using a Jupiter GPS module or Motorola ones I
Hi
I think you will find that the Z3805 uses Motorola protocol to communicate with
the GPS. If you do not have the right Motorola GPS the firmware in the Z3805
will not work.
Bob
On Feb 6, 2013, at 3:20 AM, Pierre-François (f5bqp_pfm) pfmo...@wanadoo.fr
wrote:
Hi the Timing-Gang,
I got
.
Best regards
Ulrich Bangert
-Ursprungliche Nachricht-
Von: time-nuts-boun...@febo.com
[mailto:time-nuts-boun...@febo.com] Im Auftrag von Tom Van Baak
Gesendet: Montag, 24. Dezember 2012 18:48
An: Discussion of precise time and frequency measurement
Betreff: Re: [time-nuts] Z3805A
@febo.com
Subject: Re: [time-nuts] Z3805A cooling requirements?
Message-ID: 50d90ba3.5060...@rubidium.dyndns.org
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi,
On 12/24/2012 06:47 PM, Tom Van Baak wrote:
Hi Mark,
I wouldn't place much emphasis on the Adev data for
Tau's
Mark,
On 12/26/2012 06:24 PM, Mark Spencer wrote:
Tom, Magnus, Ulrich:
Thanks for the comments and suggestions. They are appreciated and I
now have an even better understanding of why ADEV measurements are
not a good tool for characterizing the performance of oscillators that
are subject to
Volker et al..
I placed a small muffin fan near one of my Z3805's. The modest air flow seems
to have some affect on the units operation.
I've collected some ADEV data as well but don't entirely trust it yet.
Amongst other issues I had a lengthy power failure at my residence four days
ago
best not to use statistics to
describe that one event.
/tvb
- Original Message -
From: Mark Spencer mspencer12...@yahoo.ca
To: time-nuts@febo.com
Sent: Monday, December 24, 2012 6:58 AM
Subject: Re: [time-nuts] Z3805A cooling requirements?
Volker et al..
I placed a small muffin fan
Hi,
On 12/24/2012 06:47 PM, Tom Van Baak wrote:
Hi Mark,
I wouldn't place much emphasis on the Adev data for Tau's of less than 80
seconds.
Actually, just the opposite; the ADEV at short tau is very close to correct.
I've collected some ADEV data as well but don't entirely trust it yet.
Hi Volker,
On 12/22/2012 04:55 AM, Volker Esper wrote:
Although I am dog-tired it gives me no peace...
I come to the following conclusion:
- The long term Allan deviation gets worse, as long, as the effect of
EFC compensating is in the range of tau
- But: It gets back to its normal value
On 12/22/2012 06:44 PM, Volker Esper wrote:
Thank you for your statement, I have to think about it.
It seems to be clear, that ADEV/MDEV aren't the convenient tools for
characterizing such an event. My goal was to answere the question asked
in the beginning of this thread: Does a constant
I wonder if the forced convection is to strong. You don't want to
hit the limits of the oven control-range. Wonder if this is a
long-term effect and if even small adjustment to the setup can
remove the bursts of noise you are seeing.
Now, some hours after switching off the fan, I'm
Yes, I made such a setup, it's now running 22 hours. I'll post the
results in two hours or so (if nothing evil happens to the earth,
meanwhile).
Volker
Am 21.12.2012 03:35, schrieb saidj...@aol.com:
Wish I had more time to play with this setup.
How about fellow time nuts spend some time
Great plots guys!
Looking at these results I think my original claim still holds: ADEV goes up
when a fan is involved versus no fan, even on a double oven 10811..
Clearly visible on the 10811, maybe not so much on the MV89 but that unit seems
to have frequency moves into the xE-010 region on
...and we do not know how much air flow and how turbulent each of us
applied. We can only give an _idea_ of what happens and in which order
of magnitude it could be.
When Stu started the thread (elderly time nuts can surely recall) his
question was about cooling a Z38xx unit. I recommended
Hi
In most cases, when you see an OCXO (or TCXO) begin to rise past a few thousand
seconds, you are either looking at aging or the room temperature.
Bob
On Dec 21, 2012, at 9:54 PM, Volker Esper ail...@t-online.de wrote:
Here come the curves...
You'll find two diagrams. The first (named
Diagram 2 shows the MDEV values of my GPSDO varying over the time, due
to blowing air at the OCXO - not the frequency of an OCXO. I'm still
hoping, that my MDEVs do not age :-)
Am 22.12.2012 04:00, schrieb Bob Camp:
Hi
In most cases, when you see an OCXO (or TCXO) begin to rise past a few
Although I am dog-tired it gives me no peace...
I come to the following conclusion:
- The long term Allan deviation gets worse, as long, as the effect of
EFC compensating is in the range of tau
- But: It gets back to its normal value after that
- The short term deviation, however, increases
Hi
Temperature transients are not a good thing for an OCXO. If you deliberately
use the fan to create a transient, then yes the OCXO will not be happy. The
question it - what happens after the transient has settled out? The plot you
have still looks a lot like a step function.
Bob
On Dec 19,
Hi
Did I miss part of the data?
The plot I got shows about 9 minutes. Temperature step stress takes a *long*
time to settle out.
Bob
On Dec 19, 2012, at 9:56 PM, saidj...@aol.com wrote:
Not sure about that, if you look at the frequency plot after ~20 minutes in
moving air the frequency
Bob,
The ADEV plot was done after the unit had fully settled to it's new location in
front of the 53132A fan.
The Tsc5125A instrument has a limit of 9 minutes to plot the frequency drift
for some reason, so I can only show you the last 9 minutes.
The transient due to the new temperature was
and frequency measurement
Subject: Re: [time-nuts] Z3805A cooling requirements?
Bob,
The ADEV plot was done after the unit had fully settled to it's new location
in front of the 53132A fan.
The Tsc5125A instrument has a limit of 9 minutes to plot the frequency drift
for some reason, so I can only
TimeLab can talk directly to the 512x boxes via ethernet. I've also
written some Linux scripts to capture both phase data and graphs from
the 5120; happy to share with anyone who'd like them (but TimeLab is a
whole lot easier in most cases).
John
On 12/20/2012 4:09 PM, Bob Camp wrote:
Hi
On 12/20/2012 01:34 PM, Bob Camp wrote:
Hi
Temperature transients are not a good thing for an OCXO. If you deliberately
use the fan to create a transient, then yes the OCXO will not be happy. The
question it - what happens after the transient has settled out? The plot you
have still looks a
Hi!
On 12/20/2012 01:36 PM, Bob Camp wrote:
Hi
Did I miss part of the data?
The plot I got shows about 9 minutes. Temperature step stress takes a *long*
time to settle out.
I too felt the data was short. For relative mediocre oscillators I at
least measure an hour. For quality rocks,
On 12/20/2012 10:19 PM, John Ackermann N8UR wrote:
TimeLab can talk directly to the 512x boxes via ethernet. I've also
written some Linux scripts to capture both phase data and graphs from
the 5120; happy to share with anyone who'd like them (but TimeLab is a
whole lot easier in most cases).
Magnus Danielson said the following on 12/20/2012 05:29 PM:
On 12/20/2012 10:19 PM, John Ackermann N8UR wrote:
TimeLab can talk directly to the 512x boxes via ethernet. I've also
written some Linux scripts to capture both phase data and graphs from
the 5120; happy to share with anyone who'd
Wish I had more time to play with this setup.
How about fellow time nuts spend some time and present similar test data on
their OCXO's to compare?
I was interested in the 1s to 100s ADEV, and my runs were from 8 minutes to
20 minutes, certainly enough time to capture data for 1s to 100s
Hi
Ok, what happens if you keep the air gun in the exact same position and let it
stabilize for an hour with no insulation around the OCXO ?
Bob
On Dec 19, 2012, at 7:24 PM, saidj...@aol.com wrote:
Hi Bob, et. al.,
this discussion prompted my interest to see how a 10811-600160 unit that
I think the data shows that the heaters were losing ground, which would explain
the steadily falling temp of the SC cut quartz.
Thomas Knox
From: saidj...@aol.com
Date: Wed, 19 Dec 2012 21:28:15 -0500
To: time-nuts@febo.com
Subject: Re: [time-nuts] Z3805A cooling requirements?
Bob,
I
Not sure about that, if you look at the frequency plot after ~20 minutes in
moving air the frequency was still extremely close to 10.00MHz.. to
within 1E-011 of 10MHz. This is a free-running 10811.
Compare that to the plot of the OCXO I had sent out some hours ago when it
was running
, Dec 20, 2012 3:57 am
Subject: Re: [time-nuts] Z3805A cooling requirements?
Not sure about that, if you look at the frequency plot after ~20 minutes in
moving air the frequency was still extremely close to 10.00MHz.. to
ithin 1E-011 of 10MHz. This is a free-running 10811.
ompare
Steward,
What is the intended and what is the actual supply voltage? Which
current is the unit consuming?
When we know that, we can compare the power consumption with our units.
If it is in the same range, it should - with a little luck - be working
properly.
My two units are intended to
It's the same as with the SR620 TIC. As long as you have only one common
chamber for all parts, you have to make tradeoffs for everyone:
the power supply needs cooling (as much as it can get), the control loop
of the oven is not designed for additional cooling, and comparators and
further
Hi
By far the most common way to test and certify OCXO's is in moving air. It's
rare to see one get in trouble from to much ventilation. The more common
problem is thermal runaway due to inadequate ventilation.
Bob
On Dec 16, 2012, at 7:57 AM, Volker Esper ail...@t-online.de wrote:
Indeed? I didn't expect that. There are people who say, that the control
loop of OCXOs is optimized for still air and no additional cooling at all.
Said told us, that...
...a fan is about the worst thing you can do for your Z3805 it will
significantly worsen the stability of the output
Hi Volker,
You are correct on that.
Bob is right in that thermal sensitivity is measured in a thermal chamber with
constant airflow at a very constant rate and temperature. While this works, it
is also somewhat unrealistic because who is going to set up a thermal chamber
for their ocxo in the
Hi
Ok where to start.
Some typical numbers:
A DOCXO likely will be specified at around 0.3 ppb peak to peak over -30 to
+70C. That comes out to 0.003 ppb per degree. A single OCOX likely will be
specified at around 10 ppb peak to peak over -30 to +70C. That's 0.1 ppb per
degree. Yes, there
Bob,
We agree that Ocxos get real bad real fast if overheated. Not a problem in the
Z3805A box when run on a desk without clogging the vent holes, which is how
this thread started (do I need a fan for my Z3805A...)
Your stability numbers are very optimistic. There are very few single oven
One item I forgot to mention:
One of the most airflow sensitive parts inside a GPSDO is the tcxo used on the
GPS receiver. Some GPS don't even use a tcxo, just an XO. They shall remain
unnamed.
Just lightly blowing on an M12+ GPS will make it lose lock immediatly.
This is easy to try for time
Hi
When you blow on a TCXO you are setting up variable airflow. A fan produces a
constant airflow. A variable flow gives you a variable temperature. A constant
flow keeps things pretty uniform.
Environnemental chambers have pretty massive airflow. TCXO's and OCXO's do
quite well inside them.
Said,
On 12/17/2012 02:16 AM, Said Jackson wrote:
One item I forgot to mention:
One of the most airflow sensitive parts inside a GPSDO is the tcxo used on the
GPS receiver. Some GPS don't even use a tcxo, just an XO. They shall remain
unnamed.
Just lightly blowing on an M12+ GPS will make
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