[time-nuts] Re: What to expect from rubidium lock behavior?

[Wilko Bulte]

hi Paul, Bob,

Is there a significant difference between these telco-surplus Rb and the more 'fancy' ones in this regard? 

I happen to own an Efratom MRK-HLN, which, I presume, is also more geared towards "always on". So, I wonder would the MRK be better or worse compared to a telco-surplus unit? Arguably a telco-surplus unit is also of the always-on variety or?

best,
Wilko
(newbie trying to get a feel for this)

> On 11 Dec 2021, at 16:27, paul swed <paulswedb at gmail.com> wrote:
> 
> Totally agree with Bob. Same experience.
> 
> 
>> On Sat, Dec 11, 2021 at 8:12 AM Bob kb8tq <kb8tq at n1k.org> wrote:
>> 
>> Hi
>> 
>> Yes, that’s pretty normal operation for any of the telecom Rb’s. They
>> also typically drift about 1x10^-9 over the first day of operation. It’s
>> best to leave them running all the time. Second best is to turn them
>> on a couple days before you need to use them.
>> 
>> Bob
>> 
>>>> On Dec 11, 2021, at 2:23 AM, Erik Kaashoek <erik at kaashoek.com> wrote:
>>> 
>>> My rubidium frequency standard (Accubeat AR60A) finally got its nice box
>> with good cooling and some LED's showing the status.
>>> While watching the unlock LED I noticed the AR60 say's it is locked,
>> about 4 or 5 minutes after cold start, when the frequency error jumps below
>> about 1e-8
>>> It takes 2 or 3 more minutes of slow drift to become stable within
>> 1e-10. Is this to be expected?
>>> With this locking speed it is tempting to switch off the AR60A unless
>> needed for some measurement. Would daily switching on/off have any impact
>> on lifetime?
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