[Hallicrafters] Keying Ht 40

[John King]

My hallicrafters HT 40 has cathode keying and even
with the key plugged in and OPEN there is an oscilator
signal present and strongly emitted which interferes
with receiving a CW signal.

Should the HT 40 oscilator be oscilating and emitting
a signal with the key open?

There is a 47K ohm resistor and a .005 cap across the
key jack. If the .005 cap was shorted, then would
there be a low impedance to ground and look as if the
key was closed. If the 47 K resistor dropped in value
sufficiently, would that look to the cathode of the
oscilator tube as if the key was closed?

I don't believe there should be an oscilator signal
with the keying circuit in the cathode of the
oscilator tube UNKEYED. What do you think? Should the
the 6CX8 oscilator tube oscilate continuously even
with the cathodes not grounded by the CW key?

Your input will be appreciated because I can't work CW
with the oscilator running all the time. 73, John,
K5PGW  



 
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