[time-nuts] Trimble OCXOs - 6525, ... and ...

Philip Pemberton lists at philpem.me.uk
Tue Jul 8 19:14:20 EDT 2014


It seems like the 65256 is the better one to pick then -- newest 
datecode (at least in the photos), and I can actually find pinouts for it.

The 34310 C1s have apparently been scalped from old Thunderbolts and 
carry 2002 datecodes.

The 49423 on sale is apparently 2005-dated, but I can't find a pinout.

I also spotted a Micro Crystal 5V OCXO (probably single-oven) which 
looked like it might make a nice "unofficial" addition to my Racal 1992 
frequency counter (currently TCXO-equipped). Phase noise spec seems a 
bit poor, but the frequency tolerance looks OK (and significantly better 
than the TCXO, I bet).

Cheers,
Phil.


On 07/07/14 11:41, Bob Camp wrote:
> Hi
>
> I have not seen a Trimble OCXO with an internal trimmer for frequency set. They probably do exist, but they are not common among the newer (post 2001) parts.
>
> Bob
>
> On Jul 6, 2014, at 11:45 PM, Alex Pummer <alex at pcscons.com> wrote:
>
>>
>>
>> some older models have higher phase noise, the very new ones are very good, sometimes they aged out the control voltage range, needing higher control voltage to pull to 10,0000000 MHz, some of them can not be pulled to the correct frequency any more without mechanical readjustment. They have inside a trim cap to set the tuning range, which is not accessible without opening the case.The case is hermetically closed.
>> Some companies for very high performance units  filling the hermetically closed case with nitrogen, also reducing the pressure of the filing  gas bellow the atmospheric level.
>> 73
>> KJ6UHN
>> Alex
>>
>> On 7/6/2014 7:43 PM, Chuck Forsberg WA7KGX wrote:
>>> On 07/06/2014 05:38 PM, Philip Pemberton wrote:
>>>> Hi there,
>>>>
>>>> I've noticed a couple of Trimble OCXOs listed on "that auction site". Specifically, model numbers:
>>>>
>>>>   - 65256
>>>>   - 49423
>>>>   - 34310 C1
>>>>
>>>> They all seem to be 12V, 10MHz, sine-wave units. Does anyone know if there are any other differences between them? Do any specific ones perform better than the others?
>>>>
>>>> There's a bit of a price difference between them, but data on Trimble OCXOs seems to be quite sparse (a bit like data on their GPS modules, really).
>>>>
>>>> Thanks,
>>> I bought a replacement OCXO for a Thunderbolt whose OCXO had died.
>>> The pinouts are different.
>>> The housing is much taller and won't fit in the Thunderbolt enclosure.
>>> The polarity of the VCO pin is different.
>>>
>>> That said, I was able to get the kluge to work by changing the polarity of the loop gain.
>>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at 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 at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>


-- 
Phil.
lists at philpem.me.uk
http://www.philpem.me.uk/



More information about the time-nuts mailing list