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WaveyDipole · 19th Mar 2021, 6:24 pm

Went into the shed this morning and powered up the radio and FM was dead again. An FM signal was injected into the input to the 1st IF and I got an audio signal through the speaker so the IF chain seems OK at least. Looks like the IF frequency is around 10.7MHz. A wire was attached to the antenna input just next to the tuner and nothing was heard which eliminates the antenna switching and co-ax leading up to the tuner and narrows the problem down to the FM tuner section itself. I noted an oscillation off a particular coil yesterday and today it was absent which appears to narrow it to the LO I think. However before I could proceed further, the radio sprang into life and no amount of prodding would make any difference. It is begining to look like there is a thermal factor as the radio had been on for maybe 5-10 mins at this point. Will try again in the morning.

19th Mar 2021, 6:24 pm	#14
WaveyDipole Nonode Join Date: Mar 2013 Location: Leicester, UK Posts: 2,535	Re: Grundig Satellit 2000 Went into the shed this morning and powered up the radio and FM was dead again. An FM signal was injected into the input to the 1st IF and I got an audio signal through the speaker so the IF chain seems OK at least. Looks like the IF frequency is around 10.7MHz. A wire was attached to the antenna input just next to the tuner and nothing was heard which eliminates the antenna switching and co-ax leading up to the tuner and narrows the problem down to the FM tuner section itself. I noted an oscillation off a particular coil yesterday and today it was absent which appears to narrow it to the LO I think. However before I could proceed further, the radio sprang into life and no amount of prodding would make any difference. It is begining to look like there is a thermal factor as the radio had been on for maybe 5-10 mins at this point. Will try again in the morning.