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Philco 53-1350 Resistor Overheats
10-07-2017, 08:09 PM
I put in the new resistor (equal value), turned the radio on, and in a couple minutes the new resistor started to smoke/BOIL. Apparently there is too much power going in to it. What should I check next? The transformer? ???
10-08-2017, 02:52 PM
Hello, I put in new resistor from Mouser, and it got fryed! Any suggestions what to check next?
10-08-2017, 03:28 PM
Before we proceed...
Wanted Ad posts are for items or services wanted. Philco Electronic Restoration is the place for discussions of electronic problems with your Philco. Therefore your last two posts have been moved to Philco Electronic Restoration.  Now - do you have the schematic for the radio? Second question - and I am not trying to be condescending in any way, merely asking to find out - are you well versed in reading schematics and troubleshooting techniques? You need to find out what is causing that resistor to overheat. Something is likely shorted causing that resistor to draw way too much current. Without a schematic (and Nostalgia Air doesn't have the 53-1350 schematic), I would say it is not likely a power transformer causing a resistor to overheat. -- Ron Ramirez Ferdinand IN
10-08-2017, 03:51 PM
http://www.rsp-italy.it/Electronics/Radi...n/1953.pdf
Pg 88. AC set series heaters voltage doubler p/s. > I would say it is not likely a power transformer causing a resistor to overheat. < I would concur as there is no power transformer. If you haven't already replace C-17 and 18. When my pals were reading comic books I was down in the basement in my dad's workshop. Perusing his Sam's Photofoacts Vol 1-50 admiring the old set and trying to figure out what all those squiggly meant. Circa 1966 Now I think I've got! Terry 
10-08-2017, 05:28 PM
What resistor are we talking about?
Where exactly is the transformer in this radio? And, what Ron said. (About sch reading). People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
10-09-2017, 10:25 AM
(10-08-2017, 03:51 PM)Radioroslyn Wrote: > I would say it is not likely a power transformer causing a resistor to overheat. <   That's what I get for not looking up a schematic. So I was lazy. Pardon me. 
-- Ron Ramirez Ferdinand IN
10-09-2017, 01:21 PM
Yes, we ordered/received the schematics. I failed as my dad's son, when it comes to electronics! He BEGAN the only radio/tv repair/sales business in our hometown in the mid-40's. He bought all the Radio-shack testing equipment kits, and made his own. He hand BUILT the first tv in our community. I spent countless hours helping him, and didn't learn a darn thing! Very frustrating! Our son is repairing this radio, and he understands the electronics. We'll check in to the parts: C17 and C18, as we haven't changed these (or any other parts, besides the one resistor.).
THANKS to all for your guidance/patience! DLT
10-09-2017, 02:11 PM
>>Our son is repairing this radio, and he understands the electronics.
Let him come here then and ask questions directly. It's a good thing he's into it all. How old is he? People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing. 
10-09-2017, 02:45 PM
If all other parts are original then the capacitors are probably no good, at a minimum.
Greg "We are here to laugh at the odds and live our lives so well that Death will tremble to take us."
10-09-2017, 05:34 PM
[attachment=14455]
Beitmans has a nice clean copy David
10-09-2017, 08:05 PM
Yes, this radio is one of dad's originals, and it has never been touched (at least not in last 50 yrs). We'll test C-17 and 18, and see what we find. Thanks!
DLT
10-09-2017, 08:53 PM
If it was my radio would replace all paper caps and out of spec resistors. David
10-09-2017, 09:07 PM
> We'll test C-17 and 18, and see what we find.
Would bother just replace. I'd be willing to wager that C-17C is shorted and that's what burning up your 270 ohm resistor. It's common practice to replace the electrolytic caps (C-17 and 18) when servicing. Nowadays the 40uf and 20uf caps aren't standard values anymore now their 47 and 22uf. The 150v caps are now 160v. For the five caps your looking at abt $5+shipping. There also are wax/paper style caps that should be replaced. Over time the internal paper insulation breaks down and causes them to become leaky, electrically leaky. Again nowadays standard voltage rating is 630v, in your set you will probably find ones that are 200v, 400v, and 600v. Instead of paper new ones use mylar film which is much better insulator. With capacitors you can always go up in voltage rating never down and with resistor you can always go up in wattage rating but not down. http://www.tuberadios.com/capacitors/ Has caps and such @ competitive prices. GL When my pals were reading comic books I was down in the basement in my dad's workshop. Perusing his Sam's Photofoacts Vol 1-50 admiring the old set and trying to figure out what all those squiggly meant. Circa 1966 Now I think I've got! Terry
10-09-2017, 10:16 PM
(10-09-2017, 08:53 PM)David Wrote: If it was my radio would replace all paper caps and out of spec resistors. David Ditto. All caps, not just paper, except mica if present. Then you won't have to think about why things smoke. People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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