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Old 04-10-2016, 09:13 PM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Captainclock View Post
Interesting, I hope this isn't going to need a lot of realignment because I really don't know a whole lot of realignment stuff except for just what I can do by ear, I have an oscilloscope which could be used for that but I don't have a frequency generator (I had seen one once at one of the local flea markets for $20 but I didn't have the money on me at the time and when I did have the money later on I went back to go get it and it was already sold!) Anyways What is Fremodyne? And why would they use the old FM (42-50 Mhz) as the basis for this radio which uses the modern FM band? Also the FM Tuner mechanism is really interesting on this radio it uses a "piston" like mechanism that's controlled by a small gear that's mounted on the AM tuning capacitor for tuning the FM...
The set uses the slug-type tuning principle. They were a bit more stable than the regular tuning condenser. Many of those early FM sets could be aligned with an AM signal generator, by following the proceedure in the service notes. I wouldn't bother with FM alignment, as it wouldn't help that much.
The Fremodyne was a form of super-regenerative circuit, developed for inexpensive FM receivers. Heathkit, even made a kit form in the late 40's. It received FM stations, but it wasn't a true FM receiver. Fidelity wasn't that great, as it used some form of slope detection.
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