[ARC5] Radios and the Canal - Hammarlunds

[Kenneth G. Gordon]

On 17 May 2013 at 20:25, Richard Knoppow wrote:

>    The cap appears in the schematic for the SP-400 on BAMA. 
> Its across the main tuning capacitor.  The handbook 
> identfies it as a compensating cap but does not give a value 
> for either capactance or temperature coefficient.  Carl 
> mentioned it in a long ago post so I am sure he knows the 
> details.

As I said, it is a 3.3 pfd cap with at least an N-750 tempco. According to the 
Hammarlund engineer, the cap should have "as high a negative temperature 
coefficient as one can find." which seems a bit non-specific to me.

It is connected, under the capacitor shield, from the stator of the oscillator 
section of that capacitor to ground.

Re-peaking the oscillator trimmers will be required.

Ken W7EKB