[time-nuts] Temex LPFRS-01 / LPRO rubidium reference repair

[Gerd v. Egidy]

Hi Ed,

> When it locks for a few seconds, make a note of the VCXO control
> voltage.  Watch it as closely as you can during the lock period.  Is it
> very near one end of the sweep range?  Does it then drift off the end of
> the range when lock is lost?  That behaviour would suggest that the VCXO
> has drifted out of range as Bob suggested.  But if the voltage stays
> more towards the middle of the range (like 4D, 4C) that's not going to
> be the problem.  You could also watch the output frequency since it
> tracks the frequency.  Whichever is easier.

Thanks for the tips. Will try that within the next few days.

> Also, check for obvious things like bad capacitors. Living next
> to that physics package must be a hard life for any capacitor!

That was my first thought too. But I checked the capacitance and esr of all the 
al and tantalum caps - everything within reasonable values. Seems like they 
got really good quality ones and did their homework on this part of the 
design.

Kind regards,

Gerd