07-25-2026, 01:24 PM
Ed, I found that 2nd FM band to be quite interesting myself. I didn't even know it existed. I read through your thread and we are running into similar issues and fixes. So far ... I haven't heard any evidence of SMD, but, that doesn't mean it's not there playing with me. I found a Shango video where he was talking about a cap right off the detector that limits the highs at low volume settings, but his was a newer radio. I did get a TinySA, but haven't gotten it completly figured out yet. I too had to replace some bad wiring. I haven't attempted an alignment yet, but its next on the list unless SMD is present. I've also heard mica caps get noisy, even new ones. Ran into that into an amp build I did awhile back.
Here's the schematic. It is from Radio Museum, so it's in 2 parts. I think the cap Shango is talking about might be C19, but it goes to the band switch, and looks like if I clip it, then one end of the volume control is floating. May be a non issue - unless it's something to di with the AVC. I did notice that the AVC seems a little weird, meaning that some stations are much louder than others, so I may need to take a closer look. This one shows a shielded cap going to the volume control like Mikes (Morzh) on the schemo, but I don't remember finding that in my set. It looked original when I started. I even went through the paper caps I removed and double checked and didn't find it, so this radio might not have it. Anyway, I have the alignment information, but may have to do it like Mr. Carlson and inject a 10.7 mhz signal and take voltage readings at the detector transformer.
Here's the schematic. It is from Radio Museum, so it's in 2 parts. I think the cap Shango is talking about might be C19, but it goes to the band switch, and looks like if I clip it, then one end of the volume control is floating. May be a non issue - unless it's something to di with the AVC. I did notice that the AVC seems a little weird, meaning that some stations are much louder than others, so I may need to take a closer look. This one shows a shielded cap going to the volume control like Mikes (Morzh) on the schemo, but I don't remember finding that in my set. It looked original when I started. I even went through the paper caps I removed and double checked and didn't find it, so this radio might not have it. Anyway, I have the alignment information, but may have to do it like Mr. Carlson and inject a 10.7 mhz signal and take voltage readings at the detector transformer.
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44




