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Philco 38-10
#16

The drama surrounding the 2nd detector and the IF signal is finally solved ! Today my parts arrived from Dave Cantelon at Just Radios. Among therm were 100 pf and 110 pf condensers. I installed the missing 100 pf condensers in the 2nd IF can...
[Image: https://64.media.tumblr.com/5ec1fe785df6...040f0f.jpg]

I had also tested the IF (6K7G) and 2nd detector (6Q7G) tubes before this, and found that the 6Q7G I was using had gone bad. It lit up OK, but it was completely dead under test ! How it managed to pass the audio signal I don't know, or much care. I believe this was the main source of my frustration. I didn't bother to even try the radio again until after I had received and installed the 100 pf condensers. Once that was done, I set about seeing if I could finally re-align the radio. As soon as I turned it on, with my signal generator set for 470KC I was able to hear a signal when I injected the signal through a .01 MFD condenser into the grid of the IF amp.I tuned and peaked the 2nd IF transformer, then moved the input to the grid of the first detector (6A8G), and tuned and peaked the 1st IF transformer. With that done, I moved the signal input to the antenna input , and, following the alignment instructions, peaked things up finally. After that I proceeded with the rest of the alignment as the instructions describe, and everything went pretty smoothly. Tonight I will do final tweaks, and then test the radio on my outdoor antenna.
#17

Tonight I hooked up my Philco 38-10 to my outdoor antenna. She performs about exactly as well as my 37-61 did, which is not surprising considering how similar the circuits are. Here is a picture of the underside of the chassis all finished. Note that I replaced the 10K resistor with a 10K 10Watt wirewound. works a treat ! When trying to sort out the 2nd detector issue I also removed the phono input and returned the radio to original just to eliminate one other possible problem. It didn't help, but that's why it's gone.
[Image: https://64.media.tumblr.com/6589694695d3...7a0568.jpg]

And here is a picture of the radio in its cabinet, all aglow and working. I am quite pleased with her. For a glorified "All American five" she does pretty well.
[Image: https://64.media.tumblr.com/813a36269988...80bc6f.jpg]
#18

Hello Mike,
I will keep tuned to your thread on your 38-10t since that is my next project after my General electric clock radio .
I am also very lucky my Cabinet is in really nice shape too .

Sincerely Richard
#19

Mike, looks good! We all need a little repair drama now and again; if restoration always went easy, where would the fun be?

I have a 38-10T, as well as the Canuck version, a 38-C10. Cabinet and chassis on our version have slight differences, and don't use the U.S. schematic when repairing the Canadian chassis. Ask me how I know...
#20

Mike that is one good looking radio glad you got the old girl up and running. David




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