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City: Chicago,illinois
Hi fellas,
I'm cleaning up a 38-62 table top. It's been re-capped and works with a hum. I was replacing a few wires after cleaning out the volume/on-off switch. I notice 4 wires in pretty bad shape going to the power transformer. It has 9 wires coming out of it. My question is can I replace all the wires? I opened up the transformer after marking all the wires and see the top ones don't look hard to replace...however the lower ones look a little tricky. Has anyone re-wired one of these? Are there any tips you like to share? Or should I order a new one? If a new one is recommended...where should I look to purchase it? Can someone let me know which part # I would need?
Thank You,
Jimmy
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City: Merrick, Long Island, NY
If you took the bells off you could just as easily put heat shrink tubing over each wire. Try to use the same color as the original. The idea is to prevent short circuits or arcing. If the set is playing normally and the transformer does not get too hot (you should be able to touch it after it has been running for an hour without becoming burned,) you do not need to replace it. The hum is another matter, re check your work, especially polarity of electrlytics, measure voltages, etc... you'll find the problem.
Posts: 163
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City: Chicago,illinois
Thank You...That's what I just finished doing. I have it all back together. The problem I have now is...With the volume all the way down,I get a little higher than a low volume with station tuned in. However,when I try to raise the volume...I get a screech that gets louder while turning up the volume control.The music does not get louder,just the screech.
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Just looked over at nostalgiaair for the Riders schematic for the 38-62. Didn't find it there. However, I have rebuilt a few 38-62s over the years. Common Philco set with common probs. I call them boat motors because most have motorboating issues as well. If you have re-capped it, did you rebuild or sub for the orig bakelight block condensers also? If so, make sure you have tube shields on the RF tubes in the radio that require them. Sometimes the original tube shields are missing. The bases of the tubes will show if shields are missing. If the shields are missing, you can make some by cutting the top and bottom out of aluminum coke cans or similar. Cut the aluminum down the side,cut and fit height up to grid connection height on top of tube,and wrap the tubes with aluminum and tape the homemade shields around all tubes missing original tube shields . Those tube shields need to be in place because the grid connections are on top of the tubes. These particular Philco sets are as touchy as a old maid at a stag convention for eliminating random interferences. Also, other nearby household appliances such as florescent lighting fixture transformers, clothes washers, dryers, or ac line noise affect these type sets as well. Go back over your schematic and make sure you haven't missed anything. Sometimes, someone else previously possibly removed bypass caps and didn't replace all them.Having tube shields in place is critical in these sets, then look for cap bypass probs in the RF sections, and avc line as well if all else fails.
Posts: 163
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TR, I have all the shields. I ordered a set of schematics from Chuck. The one I downloaded was a 37-62 and not very readable. Thanks for the quick reply.