[time-nuts] Ancient OCXO in scope calibrator.

[Bruce Griffiths]

> Dave
>
> Need a few more circuit details.
> The crystal current wont be very high unless their are other components 
> connected to G1.
>
> Bruce
>
>   
The anode G1 capacitance is about 10fF so with 25V rms at the anode, the 
crystal current would be around 16uA if the circuit relies on feedback 
via the anode to grid 1 capacitance.
This seems to be a little low to be useful.
You could try substituting a newer 7587 there are several currently 
available on ebay and elsewhere.

Bruce