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Hi All, I am new at learning to restore the Philco radios that I have. One is a model 81 and a model 84. Will start with the 81 first. The first question is do I replace the old line cord with new cloth 2 wire non polarized plug , which is unsafe to do or do I find a polarized plug to fit the end of the cord and not use the original round end. Or is there a replacement old looking polarized end for the new cord. Or do I just use new rubber polarized cord with end already attached. I have not plugged either radio in yet to see what happens. They have not been used for decades. Don 't want to blow anything up or get electricuted. Should I ground to chassis .
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What replacement cord should I use on Model 81. Should I switch over to polarized cord. Do the new capacitors stop the chance of hot chassis.
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City: Roslyn Pa
Hi Bill and welcome,
Personally I'd go w/the cloth covered cord as it's looks original.
In the strictest sense most of the time the term Hot Chassis refers
to a set that doesn't use a power transformer and the one side of the
AC line is connected directly to the chassis. If the ac cord is plugged in
w/the hot side of the line going to the chassis you can get a good
shock from it.
This does not describe your model 81 or 84, they both have power
transformers. General overhaul on these sets requires replacement
of all the paper caps, electrolytic caps, carbon resistors. Probably
will need the ant and osc coils repaired.
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
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As this is really a separate thread from the question about power cords by another member, this has been split into its own topic.
--
Ron Ramirez
Ferdinand IN
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Welcome to the Phorum!
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Thankyou for the reply Terry, I think I am going to learn a lot from this web sit.
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City: Roslyn Pa
Your welcome. Hope I didn't overwhelm you with work to be done on these guys. I "feels" like I've fixed about 6ooo of the model 80's (in reality about a dozen or two) and their relatives (80,81,84,84B,37-84,600,37-600, and a few more down in the 50's) all have very similar circuits. Have done it both ways, gone though it troubleshooting as I go along and just replacing all the before mentioned parts. It turns out that with a few exceptions it was easier and quicker to replace.
Here's some reading materal:
http://www.tuberadioland.com/philco80Jnr_main.html
http://www.nostalgiaair.org/pagesbymodel...013843.pdf
http://philcoradio.com/phorum/showthread...odel+80+jr
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
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City: north lawrence,ohio
So being a newbie, what would be the first couple of pieces of equipment you would use. I have ohm/volt meter. There are some tube checkers on ebay. I wouldn't know which brand or model for the old 30's radio tubes. I don't know if I need one but would be good to have. What about a veriac.
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Welcome. Variac is nice to have and you want to look at getting an isolation transformer especially for the radio chassis' with out transformers.
Look up, making a dim bulb tester that will be something you can use.
Tube tester nice to have also But not an immediate need.
Oh yea, if your going to do a lot of radios you will want to get an signal generator.
(This post was last modified: 02-27-2017, 09:51 AM by KCMike.)
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Thanks, I am going to make a dim bulb tester. Right now the radio's I have do have transformers. I might not need a tube tester. My concern right now is to get the new line cord in and start getting the old tar blocks out one at a time and redo them. No paper capacitors in here. Maybe this has been redone years ago.
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Unless your planning to power up before restoration. I usually put the line cord in last after restoration. They get in the way while working on the chassis.
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Bill
To be brutally honest, dim light bulb tester is not even a poor man's variac, it is.....everything in me speaks against it.
A small 500VA variac is not expensive and it is all you will ever need.
Having an isolating transformer helps safety. Also not a bank-breaker.
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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You can make a crude substitute for a variac by using a string of old style Christmas lights (the type with the C7 bulbs) wired as a dim bulb tester. Leave all the bulbs loose to start with, tighten them one at a time to bring the voltage up slowly, You may want to replace a couple of the bulbs with 25 watt for a course adjustment.
Yeah, I know, I'm a bit of a cobble artist. 
Steve
M R Radios C M Tubes
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Not even plugged it in. Maybe will get a variac. Don't know about the Christmas light idea. Not bad though. I will plug it into a GFI when I do get ready to plug it in. Just in case.
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<So being a newbie, what would be the first couple of pieces of equipment you would use.
Well a good volt ohm meter analog or digital. You can use it to do a basic test on tubes to determine if they are usable or dead along with checking lots of voltages the resistances in your set which can find faulty parts.
Signal generator for doing alignment and testing various stages of your set.
Frequency counter. Inexpensive one can be had from China @ $10. Use to check the accuracy of your signal generator and can be used to check the local oscillator of a non working set.
Signal tracer allows you to hear a signal at the input and output of each stage. This can be very handy when looking for a non working stage.
These would be the things I use the most.
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
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