I have not found or seen any official documentation for this board or the Trimble equivalents.(you can google for Trimble 63090 or 73090)
You can enable a once per second string but it is hex data string, not NMEA data.
As Brainbox mentioned the 4 mounting holes are not all ground - one of them is connected to the 5 volt regulator.
The M-act button does manually enable the 10 MHz output even if no GPS lock has been achieved. In the case of the my Trimble which has been running for months constantly it is very accurate in the short term from a cold start. With no GPS connected after the oven is warm it is currently within 4 mHz of proper 10 MHz. So if you had to take the unit out of the lab and just needed a quick reference it would do quite nicely even without GPS lock.
I have not found or seen any official documentation for this board or the Trimble equivalents.(you can google for Trimble 63090 or 73090)
You can enable a once per second string but it is hex data string, not NMEA data.
As Brainbox mentioned the 4 mounting holes are not all ground - one of them is connected to the 5 volt regulator.
The M-act button does manually enable the 10 MHz output even if no GPS lock has been achieved. In the case of the my Trimble which has been running for months constantly it is very accurate in the short term from a cold start. With no GPS connected after the oven is warm it is currently within 4 mHz of proper 10 MHz. So if you had to take the unit out of the lab and just needed a quick reference it would do quite nicely even without GPS lock.
Some questions about M-act and GPSDOs in general:
When you press the M-act button does it output the 10 MHz signal continuously (until you press the button again), or does it output the 10 MHz signal only while you hold the button down?
If you don't use the antenna and you are happy being within 4 mHz of properly 10 MHz (I presume that is within in 4 milliHertz), can the system operate in this reduced accuracy mode indefinitely? (For example if you don't have a good place to mount the antenna?) Or is this reduced accuracy mode only available after you have initially established a GPS signal with the antenna?
Does a GPSDO antenna need to be outside with line of sight or can it be outside without line of sight, or inside with line of sight, or inside without line of sight?
Sorry for asking this (I know it's been discussed in other threads but I don't recall the conclusion), but is it better to use a GPSDO 10 MHz sine wave or square wave for a clock input to test equipment (frequency counter, oscilloscope, spectrum analyzer, etc.)? Same answer or different answer when providing a clock input for communications equipment (ham transceivers, etc.)?
Last question (for now), what is the purpose of the 1 PPS Output vs the 10 MHz Output?
Thanks!
I have not found or seen any official documentation for this board or the Trimble equivalents.(you can google for Trimble 63090 or 73090)
You can enable a once per second string but it is hex data string, not NMEA data.
As Brainbox mentioned the 4 mounting holes are not all ground - one of them is connected to the 5 volt regulator.
The M-act button does manually enable the 10 MHz output even if no GPS lock has been achieved. In the case of the my Trimble which has been running for months constantly it is very accurate in the short term from a cold start. With no GPS connected after the oven is warm it is currently within 4 mHz of proper 10 MHz. So if you had to take the unit out of the lab and just needed a quick reference it would do quite nicely even without GPS lock.
Some questions about M-act and GPSDOs in general:
When you press the M-act button does it output the 10 MHz signal continuously (until you press the button again), or does it output the 10 MHz signal only while you hold the button down?
If you don't use the antenna and you are happy being within 4 mHz of properly 10 MHz (I presume that is within in 4 milliHertz), can the system operate in this reduced accuracy mode indefinitely? (For example if you don't have a good place to mount the antenna?) Or is this reduced accuracy mode only available after you have initially established a GPS signal with the antenna?
Does a GPSDO antenna need to be outside with line of sight or can it be outside without line of sight, or inside with line of sight, or inside without line of sight?
Sorry for asking this (I know it's been discussed in other threads but I don't recall the conclusion), but is it better to use a GPSDO 10 MHz sine wave or square wave for a clock input to test equipment (frequency counter, oscilloscope, spectrum analyzer, etc.)? Same answer or different answer when providing a clock input for communications equipment (ham transceivers, etc.)?
Last question (for now), what is the purpose of the 1 PPS Output vs the 10 MHz Output?
Thanks!
Hi
The OCXO has an unknown aging spec (could be 1 ppb / day). It also has an unknown retrace spec (could be 1 ppb over 24 hours). What is the temperature stability? Again, who knows. Warmup ... orientation .... voltage .... who knows. If it holds 10 ppb for a week without the antenna, it's doing ok.
(1 Hz at 10 MHz is 100 ppb ...).
Bob
That's cool but I'm still hoping to get some answers to questions I asked
If you don't use the antenna and you are happy being within 4 mHz of properly 10 MHz (I presume that is within in 4 milliHertz), can the system operate in this reduced accuracy mode indefinitely? (For example if you don't have a good place to mount the antenna?) Or is this reduced accuracy mode only available after you have initially established a GPS signal with the antenna?
Does a GPSDO antenna need to be outside with line of sight or can it be outside without line of sight, or inside with line of sight, or inside without line of sight?
Sorry for asking this (I know it's been discussed in other threads but I don't recall the conclusion), but is it better to use a GPSDO 10 MHz sine wave or square wave for a clock input to test equipment (frequency counter, oscilloscope, spectrum analyzer, etc.)? Same answer or different answer when providing a clock input for communications equipment (ham transceivers, etc.)?
Last question (for now), what is the purpose of the 1 PPS Output vs the 10 MHz Output?
Some questions about M-act and GPSDOs in general:
When you press the M-act button does it output the 10 MHz signal continuously (until you press the button again), or does it output the 10 MHz signal only while you hold the button down?
If you don't use the antenna and you are happy being within 4 mHz of properly 10 MHz (I presume that is within in 4 milliHertz), can the system operate in this reduced accuracy mode indefinitely? (For example if you don't have a good place to mount the antenna?) Or is this reduced accuracy mode only available after you have initially established a GPS signal with the antenna?
Does a GPSDO antenna need to be outside with line of sight or can it be outside without line of sight, or inside with line of sight, or inside without line of sight?
Sorry for asking this (I know it's been discussed in other threads but I don't recall the conclusion), but is it better to use a GPSDO 10 MHz sine wave or square wave for a clock input to test equipment (frequency counter, oscilloscope, spectrum analyzer, etc.)? Same answer or different answer when providing a clock input for communications equipment (ham transceivers, etc.)?
Last question (for now), what is the purpose of the 1 PPS Output vs the 10 MHz Output?
Thanks!
in general, you need some level of visibility towards the equator.
When you press the M-act button does it output the 10 MHz signal continuously (until you press the button again), or does it output the 10 MHz signal only while you hold the button down?
If you don't use the antenna and you are happy being within 4 mHz of properly 10 MHz (I presume that is within in 4 milliHertz), can the system operate in this reduced accuracy mode indefinitely? (For example if you don't have a good place to mount the antenna?) Or is this reduced accuracy mode only available after you have initially established a GPS signal with the antenna?
Does a GPSDO antenna need to be outside with line of sight or can it be outside without line of sight, or inside with line of sight, or inside without line of sight?
Sorry for asking this (I know it's been discussed in other threads but I don't recall the conclusion), but is it better to use a GPSDO 10 MHz sine wave or square wave for a clock input to test equipment (frequency counter, oscilloscope, spectrum analyzer, etc.)? Same answer or different answer when providing a clock input for communications equipment (ham transceivers, etc.)?
Last question (for now), what is the purpose of the 1 PPS Output vs the 10 MHz Output?
Thanks!
in general, you need some level of visibility towards the equator.
If you're further than north or south 60 degrees, all satellites will be towards the equator. So an antenna location that has good visibility towards the equator will maximize the number of satellites that you can see.
if you want some monitoring software running under windows, here it is:
http://www.romahn.info/symmetricom/Z38SY.ZIP
I've patched Ulrich Bangert's famous Z38XX to at least partially work with our Symmetricom UCCM-P.
For use first set the right "parameters" i.e. your com-port and hit ok.
Try the various functions under the "view" tab.
KutteHallo Kutte super Programm , vielen Dank hier für das posten !!!
Gruß Dieter
if you want some monitoring software running under windows, here it is:
http://www.romahn.info/symmetricom/Z38SY.ZIP
I've patched Ulrich Bangert's famous Z38XX to at least partially work with our Symmetricom UCCM-P.
For use first set the right "parameters" i.e. your com-port and hit ok.
Try the various functions under the "view" tab.
KutteHallo Kutte super Programm , vielen Dank hier für das posten !!!
Gruß Dieter
I wandered over to the website for the programmer. Sadly it looks like he passed away a couple years ago.
Hi
There has been an effort to continue Ulrich's work. It's not super active.
Bob
Hi
There has been an effort to continue Ulrich's work. It's not super active.
BobPassed away far too early. He also did the excellent EZGPIB, which is just as tiny and completely bloatware and installer-less as Z38XX.
In order to continue then the source-code must be out there? A complete re-write would be easier than reverse engineering.
Apparently a neighbor / friend has access to the source code and has issued one or two minor patched versions. Based on a lot of correspondence back when the code was being developed -- there was a lot of guessing going on. Much of the protocol information was incomplete. The code was written so the outputs looked sensible on the GPSDO's available at that time. I suspect that without the notes on how this or that was come up with, the source code might not be very useful.
Apparently a neighbor / friend has access to the source code and has issued one or two minor patched versions. Based on a lot of correspondence back when the code was being developed -- there was a lot of guessing going on. Much of the protocol information was incomplete. The code was written so the outputs looked sensible on the GPSDO's available at that time. I suspect that without the notes on how this or that was come up with, the source code might not be very useful.I've always been of the opinion that ultimately the code IS the documentation. Merciless refactoring is also not a problem. (That was the political term used to get a pointy head project manager agree to a complete rewrite without knowing it. I think they have cottoned on by now! ).
Any source-code is better than no source-code. That's why we have such a big thing about open source!
Please help out a new player...
I have the output of the 10MHz and I want to feed this into my LT6551 which is fed with 3V3 and will give a gain of 2. So I want to have a signal that is roughly 1V6 pp I will then bias it so it varies 0 to +1v6...
Observing the output of the UCCM-P when put into my Rigol which is high Z... I see approx 2V9 pp.
Into 50 Ohms this gets squashed to a dismal 520mV pp...
... into 67 Ohms I get 1V84
into 117 Ohms I get 2V28
into 78k Ohms I get pretty much the same as high Z... 2v8... 2v9 ish
I assume all this is trying to tell me something about the output impedance of the device... do I just pick a number around 60 ohms or is more thought required?
UCCM-P > diagnostic:loop?
-------------------------------------------------------------------------------
5/18/2016 05:19:02
-------------------------------------------------------------------------------
LOS MEAS NCO STATUS WEIGHT PBUC FBUC DBUC LBUC IBUC G M TC
-------------------------------------------------------------------------------
0: 1 0.000e+00 0.000e+00 0x07AC X 700 700 0 0 2 2 4 29
1: 1 0.000e+00 0.000e+00 0x068C X 700 700 0 0 0 2 14 226
GPS: 0 2.524e-09 -5.123e-09 0x0000 1 ---- 1000 1000 ---- ---- 3 6 31
-------------------------------------------------------------------------------
freq cor = -5.122888e-09
phase cor = 2.000000e-11
gps phase = 2.333333e-09
temp cor = -8.082023e-11
Command Complete
The output of the device likely goes through a filter. The filter tuning is set up to work at a specific load impedance (likely 50 ohms). Change the load impedance and you change the characteristics (cutoff, attenuation) of the filter.
freq cor = -5.122888e-09
phase cor = 2.000000e-11
gps phase = 2.333333e-09
Or look at this one < http://www.kolumbus.fi/~ks9292/10MHz_Rubidium_standard/Dist_amp_sch.pdf >