[time-nuts] Re: FS740 Thoughts?

[Brooke Clarke]

Hi Dana:

My PRS10 is a couple decades old and I use it in the 1PPS locking mode.  But that may not have been the default.  Maybe 
the surplus units just need the correct jumper change.
https://prc68.com/I/PRS10.shtml

-- 
Have Fun,

Brooke Clarke
https://www.PRC68.com
axioms:
1. The extent to which you can fix or improve something will be limited by how well you understand how it works.
2. Everybody, with no exceptions, holds false beliefs.

-------- Original Message --------
> But if you can stand the ADEV hump around 2 sec, the PRS-10 is delightful.
>
> BTW, the ordinary factory new PRS-10 does provide for direct locking to 1
> PPS,
> but many of the available surplus units had that feature removed.  Tne new
> PRS-10's sold for years for $1595, but I see that it has gone up to $1695
> since
> I had last checked.
>
> Dana
>
>
> On Wed, Nov 17, 2021 at 9:52 AM Bob kb8tq <kb8tq at n1k.org> wrote:
>
>> Hi
>>
>> In this case it’s not thermal. I’ve tested a ton of parts in the same
>> environment ( maybe
>> not 2,000 pounds but several hundred OCXO’s ).
>>
>> The PRS-10 gives you that hump at 2 seconds no matter what you do. It’s
>> part of the
>> basic design of the unit ….
>>
>> Bob
>>
>>> On Nov 17, 2021, at 10:16 AM, Matt Huszagh <huszaghmatt at gmail.com>
>> wrote:
>>> Bob kb8tq <kb8tq at n1k.org> writes:
>>>
>>>> I have a 740 as do others on the list. The big gotcha is the OCXO in
>> the device.
>>>> It has various quirks that limit the performance of the device. The
>> ADEV plot they
>>>> show for the OCXO is a “sometimes / maybe / might” sort of thing. One
>> of the
>>>> “get to it eventually” projects here is to see if it can be replaced
>> with something
>>>> that has better ADEV performance.
>>> Good to know. Have you tried disciplining the PRS-10 in one of these
>>> units? Based on Dana's comments, it sounds like this may not exhibit the
>>> same ADEV susceptibility to the thermal environment.
>>>
>>> Matt
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