[EdHolland]

Success! (at last).

The frog is back together and receiving well. The AM wide reception now sounds correct when the radio is tuned exactly on frequency. Beforehand, it sounded slightly mis-tuned, and the peak indication of tuning was also off frequency. In the narrow setting, with the IF routed through a different filter, everything was spot on.

I've seen this problem a couple of times before. The most severe case, and the first I had seen, was in a receiver that was very much top of the line when they were new. In that radio, the filter was the first in the 455 kHz IF chain, always in circuit and was so far off center frequency - by about 9 kHz - that nothing sounded right. The misalignment also knocked sensitivity right down when using the narrow filters for USB/LSB/CW. Since I had never seen a fault like this before, it took some detective work to figure out what was going on. Even though it didn't put the receiver back to full spec. until I found a replacement filter, it was very rewarding to know the trouble had been isolated when temporary substitution with a resistor as a test brought the set back to life. A new filter completed the job This was a radio I had never expected to own, and thinking back to being a teenager, certainly one I had never expected to diagnose and repair!