[time-nuts] Aging 5065A ?

[Ulf Kylenfall]

Regarding the quest to keep a 5065A running... 


The 5065 in my hobby corner was equipped with the firstversion of the AC-Amplifier (A7) that did not have a frequency
selective 2nd harmonic detector. So I copied the later
design but made possible the use of selected polyester
precision audio capacitors for the resonant parts and
also replaced the 709's not with 741's but OP07.

That design was uploaded to KO4BB (Complete with layout
and gerber /NC-data should anyone want to copy it.)
I have not received any comments but it works 
really fine.

The Rb cavity was equipped with a thermal breaker
recommended by Corby D. The linear power supply
was replaced with a switched 24V unit (with DC filtering!)
and the instrument now runs pretty cool. The only heat
I can feel with my hands are just right above the
Rb cavity.

I wonder how many 5065A's that are in professional use
today. Or if all have been salvaged by time-nuts...

Ulf KylenfallSM6GXV