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Zenith 7s488 assistance request
#20

I’ll admit that super het theory is largely a mystery to me so please bear with me. I tried to get a signal through the radio- both through the antenna and through the IF section with no luck. My signal generator is marginal so that may not mean much. 
I’d read that you can check for an operating oscillator with another AM radio placed nearby. For what it’s worth the operating radio responded when tuning the non operating radio but not the opposite. 
The next plan is to take out the band switch. That entails a LOT of part removal. I have a donor radio coming next week that might help things. Hopefully I can double check my work and compare voltages. 
It would be easy to fake things by putting another radio in the console and running it through the TV plug. (Can you imagine TV audio on AM?) Then there’s the phonograph end of the console! Fortunately I like a challenge. As always your thoughts and encouragement are appreciated! - Rob


Messages In This Thread
Zenith 7s488 assistance request - by Rob Quay - 07-24-2022, 09:14 PM
RE: Zenith 7s488 assistance request - by morzh - 07-25-2022, 08:40 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-26-2022, 07:52 AM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-26-2022, 02:36 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-26-2022, 04:32 PM
RE: Zenith 7s488 assistance request - by MrFixr55 - 07-26-2022, 07:49 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-26-2022, 08:47 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-27-2022, 02:03 PM
RE: Zenith 7s488 assistance request - by morzh - 07-27-2022, 08:33 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-27-2022, 11:46 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-28-2022, 08:51 PM
RE: Zenith 7s488 assistance request - by MrFixr55 - 07-29-2022, 04:59 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-31-2022, 08:42 AM
RE: Zenith 7s488 assistance request - by morzh - 07-31-2022, 11:08 AM
RE: Zenith 7s488 assistance request - by Rob Quay - 07-31-2022, 09:53 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-03-2022, 09:27 AM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-11-2022, 09:21 AM
RE: Zenith 7s488 assistance request - by MrFixr55 - 08-16-2022, 11:42 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-17-2022, 09:33 AM
RE: Zenith 7s488 assistance request - by MrFixr55 - 08-17-2022, 09:14 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-18-2022, 09:12 AM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-20-2022, 10:10 AM
RE: Zenith 7s488 assistance request - by MrFixr55 - 08-21-2022, 10:04 AM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-21-2022, 11:14 AM
RE: Zenith 7s488 assistance request - by MrFixr55 - 08-21-2022, 05:55 PM
RE: Zenith 7s488 assistance request - by Rob Quay - 08-21-2022, 09:29 PM



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