03-06-2026, 04:54 PM
Hello SlidesK,
It took me a while to find a schematic I could read. It's in Rider's vol.18. The only adjustment for the AM Oscillator is C401b. You can try that adjustment at the setting of 600kHz and see if it gives you better tracking. About 75% of vintage radios have a separate adjustment padder for the lower end of the broadcast band. You may want to check the fixed mica caps in the oscillator circuit (12AU7 tube) for correct values and leakage. If one of those is off then it'll give your symptoms.
It took me a while to find a schematic I could read. It's in Rider's vol.18. The only adjustment for the AM Oscillator is C401b. You can try that adjustment at the setting of 600kHz and see if it gives you better tracking. About 75% of vintage radios have a separate adjustment padder for the lower end of the broadcast band. You may want to check the fixed mica caps in the oscillator circuit (12AU7 tube) for correct values and leakage. If one of those is off then it'll give your symptoms.
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