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Model 71 oscillator
#1

This problem is intermittent. When it occurs, the receiver is dead below about 1200 kHz. Looking at the cathode of the 37 oscillator with an oscilloscope, I can verify the 260 kHz oscillator output declines to zero at about 1200 on the dial. (A second receiver confirms this.) Thoughts on this? Yes, the receiver had been working well. I’m thinking it’s the oscillator coils, or (gasp) the autodyne circuit? But this is a new problem for me. Thanks.

Richard


Messages In This Thread
Model 71 oscillator - by WB5NEN - 09-06-2020, 02:17 PM
RE: Model 71 oscillator - by Steve Davis - 09-06-2020, 10:16 PM
RE: Model 71 oscillator - by Radioroslyn - 09-07-2020, 08:39 AM
RE: Model 71 oscillator - by WB5NEN - 09-07-2020, 05:16 PM
RE: Model 71 oscillator - by WB5NEN - 09-07-2020, 07:32 PM
RE: Model 71 oscillator - by Radioroslyn - 09-07-2020, 07:53 PM
RE: Model 71 oscillator - by WB5NEN - 09-07-2020, 10:15 PM
RE: Model 71 oscillator - by WB5NEN - 09-08-2020, 01:57 PM
RE: Model 71 oscillator - by Radioroslyn - 09-08-2020, 07:58 PM
RE: Model 71 oscillator - by Steve Davis - 09-08-2020, 11:47 PM
RE: Model 71 oscillator - by WB5NEN - 09-09-2020, 04:19 PM
RE: Model 71 oscillator - by Radioroslyn - 09-09-2020, 06:57 PM
RE: Model 71 oscillator - by RodB - 09-09-2020, 07:00 PM
RE: Model 71 oscillator - by Radioroslyn - 09-09-2020, 08:49 PM
RE: Model 71 oscillator - by WB5NEN - 09-09-2020, 10:18 PM
RE: Model 71 oscillator - by Radioroslyn - 09-10-2020, 08:07 AM
RE: Model 71 oscillator - by WB5NEN - 09-10-2020, 08:50 AM
RE: Model 71 oscillator - by RodB - 09-10-2020, 08:57 AM
RE: Model 71 oscillator - by Radioroslyn - 09-10-2020, 10:34 AM
RE: Model 71 oscillator - by rfeenstra - 09-10-2020, 04:46 PM
RE: Model 71 oscillator - by WB5NEN - 09-10-2020, 10:43 PM
RE: Model 71 oscillator - by rfeenstra - 09-11-2020, 09:38 AM
RE: Model 71 oscillator - by WB5NEN - 09-11-2020, 10:07 AM
RE: Model 71 oscillator - by rfeenstra - 09-11-2020, 12:54 PM
RE: Model 71 oscillator - by rfeenstra - 09-11-2020, 01:05 PM
RE: Model 71 oscillator - by WB5NEN - 09-14-2020, 06:58 PM
RE: Model 71 oscillator - by Radioroslyn - 09-15-2020, 09:46 AM
RE: Model 71 oscillator - by WB5NEN - 09-15-2020, 12:00 PM
RE: Model 71 oscillator - by WB5NEN - 09-18-2020, 07:29 PM



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