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Signal Injection Question
#21

Correct means nothing comes out when the 550-1600 kHz modulated signal injected in antenna wire but when 455 kHz is injected in the grid of 7A8 it does produce sound. Correct?


Now, there might be a case of 7A8 not functioning properly. The fact that 455kC goes through means your IF filter's ok and the amp!ifying part of 7A8 is ok.
The fact that nothing else goes through might mean that 1) your oscillator doesn't oscillate or 2) badly off. This calls for looking at T3 coil, the C1 section of the tuning cap, and everything else around the 7A8 except the IF xfmr T1 as obviously it is ok.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Signal Injection Question - by Welder - 12-24-2017, 06:02 AM
RE: Signal Injection Question - by Phlogiston - 12-24-2017, 11:13 AM
RE: Signal Injection Question - by Welder - 12-24-2017, 11:51 AM
RE: Signal Injection Question - by Phlogiston - 12-24-2017, 12:00 PM
RE: Signal Injection Question - by morzh - 12-24-2017, 12:07 PM
RE: Signal Injection Question - by Radioroslyn - 12-24-2017, 12:41 PM
RE: Signal Injection Question - by Welder - 12-24-2017, 03:17 PM
RE: Signal Injection Question - by morzh - 12-24-2017, 04:41 PM
RE: Signal Injection Question - by Welder - 12-24-2017, 06:20 PM
RE: Signal Injection Question - by David - 12-24-2017, 10:01 PM
RE: Signal Injection Question - by David - 12-24-2017, 10:12 PM
RE: Signal Injection Question - by morzh - 12-24-2017, 11:45 PM
RE: Signal Injection Question - by Welder - 12-25-2017, 05:49 AM
RE: Signal Injection Question - by Welder - 12-25-2017, 05:54 AM
RE: Signal Injection Question - by morzh - 12-25-2017, 07:41 PM
RE: Signal Injection Question - by Welder - 12-25-2017, 10:25 PM
RE: Signal Injection Question - by morzh - 12-25-2017, 10:37 PM
RE: Signal Injection Question - by Welder - 12-26-2017, 07:12 AM
RE: Signal Injection Question - by Welder - 12-26-2017, 07:12 AM
RE: Signal Injection Question - by morzh - 12-26-2017, 11:59 AM
RE: Signal Injection Question - by Welder - 12-26-2017, 09:50 PM
RE: Signal Injection Question - by morzh - 12-26-2017, 10:33 PM
RE: Signal Injection Question - by Radioroslyn - 12-27-2017, 01:08 AM
RE: Signal Injection Question - by Welder - 12-27-2017, 07:10 AM
RE: Signal Injection Question - by morzh - 12-27-2017, 10:23 AM
RE: Signal Injection Question - by Welder - 12-27-2017, 01:37 PM
RE: Signal Injection Question - by oldswab37 - 12-27-2017, 04:37 PM
RE: Signal Injection Question - by Welder - 12-27-2017, 06:04 PM
RE: Signal Injection Question - by morzh - 12-27-2017, 06:09 PM
RE: Signal Injection Question - by Welder - 12-27-2017, 07:47 PM
RE: Signal Injection Question - by morzh - 12-28-2017, 01:02 AM
RE: Signal Injection Question - by Welder - 12-28-2017, 05:19 AM
RE: Signal Injection Question - by morzh - 12-28-2017, 12:56 PM
RE: Signal Injection Question - by morzh - 01-03-2018, 10:10 PM
RE: Signal Injection Question - by Welder - 01-04-2018, 05:51 AM
RE: Signal Injection Question - by morzh - 01-04-2018, 02:50 PM
RE: Signal Injection Question - by Welder - 01-04-2018, 06:41 PM
RE: Signal Injection Question - by morzh - 01-04-2018, 06:52 PM
RE: Signal Injection Question - by Welder - 01-08-2018, 05:41 PM
RE: Signal Injection Question - by morzh - 01-08-2018, 05:48 PM
RE: Signal Injection Question - by Welder - 01-08-2018, 07:05 PM
RE: Signal Injection Question - by jcassity - 01-17-2018, 10:07 AM
RE: Signal Injection Question - by morzh - 01-17-2018, 10:53 AM
RE: Signal Injection Question - by jcassity - 01-17-2018, 11:13 AM
RE: Signal Injection Question - by morzh - 01-17-2018, 02:50 PM



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