[time-nuts] Thunderbolt E failing

[Bob kb8tq]

Hi

The unit your link points to *is* the “classic” TBolt that showed up in volume a bit
over a decade ago. That one is packaged with a (noisy) switching power supply. 

There is no easy way to tell what era it is from. Indeed if it is from the 1990’s the 
OCXO will not be quite as good as what’s in one from > 2002. Since the unit normally
operates locked, that’s not a real big deal. 

Since Trimble used “Thunderbolt” for a whole line of parts *and* was not very good
at labeling devices, there is no easy way to refer to this or that specific device. That
makes coming up with a list of units a bit hard. For example - what’s the model number
of the part in that eBay listing ? ( No I don’t know either …. :) ).

Bob

> On Sep 12, 2020, at 12:28 PM, Adrian Godwin <artgodwin at gmail.com> wrote:
> 
> I've been looking for a thunderbolt for a while, mostly because they're
> such a benchmark within this group. I missed the period when they were more
> commonly available and have mostly found ones that were a lot more
> expensive, or had a large delivery cost due to being in Australia.
> 
> Some cheaper examples turned up on UK ebay. These aren't the classic
> time-nuts ones but presumably look fairly similar to Lady Heather.
> 
> https://www.ebay.co.uk/itm/154078750287
> 
> I haven't been able to find a comparison of the various thunderbolt models.
> Is there a description somewhere ? I've found a few hints about this one -
> I think it's a single 48V supply and possibly a lower-quality OCXO.
> 
> On Sat, Sep 12, 2020 at 5:14 PM Kevin Schuchmann <kschuchm at gmail.com> wrote:
> 
>> Matthias,
>>    You are correct, having spent hours looking at all the stable areas
>> and cooling and heating the gpsdo I find that when it reports that it is
>> 116.25 F then it is stable.
>> So now I guess I need to figure out why it is so picky. I will measure
>> the current draw from a cold start and see if I see the oven warming up
>> and then stabilizing and then heat and cool it and see how it reacts,
>> and also look at the electronics and see if an area is overly sensitive
>> to temperature.
>> 
>> Thanks
>> Kevin
>> 
>> 
>> On 9/11/2020 2:26 AM, Matthias Welwarsky wrote:
>>> On Freitag, 11. September 2020 01:08:09 CEST Kevin Schuchmann wrote:
>>>> Guess my image didn't make it, I will add it as an attachment this time.
>>> The temperature curve seems to show some correlation to what is
>> happening with
>>> the DAC. Seems that the DAC and OSC jumps are mostly during periods of
>> some
>>> thermal perturbation.
>>> 
>>> Regards,
>>> Matthias
>>> 
>>> 
>>> 
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at lists.febo.com
>>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>>> and follow the instructions there.
>> 
>> 
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at lists.febo.com
>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.