[AMRadio] Ranger Xtal Oscillator

Rick Brashear rickbras at airmail.net
Sat Nov 11 14:52:27 EST 2006

The modulator bias is derived from the 6AL5 supply.  I would be cautious 
completely disabling the grid block keyer as it is tied into the VFO and 
the crystal oscillator.  I'm sure with careful planning it could be 
disabled, but I can't really see any advantage to doing so since you can 
simply avoid the "CW" position on the "Operate" switch.  It may be the 
keyer that is causing your "Standby" problem, but until I found the 
precise problem I don't think I would disable anything for fear of 
masking the underlying problem.


Jack Schmidling wrote:

> Rick Brashear wrote:
>> Jack,
>> You might check R7 and C23 to be sure they are in tolerance.  Swap 
>> the two 6CL6 tubes (V3 and V4) with each other (or with known good 
>> ones) and see if that helps. 
> I tried new tubes but that didn't help.  I am going to put it back on 
> the bench and check the other components.
> However, as I am not interested in CW, wouldn't it make sense just to 
> disable the keyer?
> Also, the bias supply seems to be an after thought.  Does it have 
> anything to with the keyer and why was it added?
> js

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