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Model 60 6A7 oscilator distortion
#1

Hello. I have a Model 60 run 7 that has been re-capped, re-resistored, and ant coil rewound. It has low sensitivity and is noisy below 650 KHz. Looking at the 6A7 oscillator waveform using a non-contact probe on an oscilloscope shows considerable distortion and and about a 5:1 attenuation of the signal as the radio is tuned towards the higher frequencies. A check with a spectrum analyzer shows multiple harmonics of the oscillator fundamental present. Is this distortion and attenuation normal? What might be the cause? It does not seem to affect the quality of the reception at the higher frequencies. I have tried two different "good" 6A7's with the same result. The radio works fine at frequencies above about 650 KHz. Thanks.

-Bill Kushner
Arl.Hts IL


Messages In This Thread
Model 60 6A7 oscilator distortion - by koosh01 - 11-28-2018, 03:53 PM
RE: Model 60 6A7 oscilator distortion - by AI2V - 12-29-2018, 04:55 PM



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