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Zenith 15U270
#20

To every change there are consequences! By broadening out the IF response curve, I reduced the sensitivity. Now, with a very strong signal, I get a lot of distortion. I presume the strong signal is over driving the RF stage since the AVC is not shutting the RF and Detector amps down enough. I'll have to take some AVC voltage measurements with the IF peaked and compare it with the broadened IF AVC voltages. Perhaps changing one resistor will bring it in line again. It's fun to fiddle!


Messages In This Thread
Zenith 15U270 - by rfeenstra - 05-31-2020, 04:45 PM
RE: Zenith 15U270 - by rfeenstra - 05-31-2020, 04:54 PM
RE: Zenith 15U270 - by morzh - 05-31-2020, 06:10 PM
RE: Zenith 15U270 - by rfeenstra - 05-31-2020, 08:06 PM
RE: Zenith 15U270 - by morzh - 05-31-2020, 08:39 PM
RE: Zenith 15U270 - by Eliot Ness - 06-01-2020, 08:07 AM
RE: Zenith 15U270 - by rfeenstra - 06-04-2020, 08:12 PM
RE: Zenith 15U270 - by sdradioman - 06-05-2020, 07:06 AM
RE: Zenith 15U270 - by rfeenstra - 06-05-2020, 10:12 PM
RE: Zenith 15U270 - by morzh - 06-05-2020, 11:44 PM
RE: Zenith 15U270 - by Phlogiston - 06-06-2020, 10:46 AM
RE: Zenith 15U270 - by rfeenstra - 06-06-2020, 11:23 AM
RE: Zenith 15U270 - by rfeenstra - 06-06-2020, 06:23 PM
RE: Zenith 15U270 - by Phlogiston - 06-06-2020, 08:56 PM
RE: Zenith 15U270 - by rfeenstra - 06-06-2020, 09:47 PM
RE: Zenith 15U270 - by Phlogiston - 06-06-2020, 10:34 PM
RE: Zenith 15U270 - by rfeenstra - 06-09-2020, 09:14 PM
RE: Zenith 15U270 - by PhilcoJohn - 06-10-2020, 08:27 AM
RE: Zenith 15U270 - by Phlogiston - 06-11-2020, 11:32 AM
RE: Zenith 15U270 - by rfeenstra - 06-11-2020, 03:31 PM



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