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Philco 80 7421 Transformer
#1

Is there away to take this transformer apart and redo the wires. The isolation on the wire is very brittle. If I move the wire it cracks.
#2

I don't have a parts list for that set so I'm not sure which transformer you are referring to. However don't know if it matters much. I'm thinking it's the power transformer. The simplest thing to do is unsolder the wire and slip the appropriate sized shrink tubing over it and then use a heat gun to shrink it. Resolder and your done.
Terry

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 it!

Terry
#3

I have done the shrink tubing its just now I have move them again worried that the the readings I'm getting are wrong. They are different than the first time.
#4

7421 is the part number for the model 80 power transformer.
How did the values change from your original measurements?

Carl
Northern Panhandle, WV
#5

Sounds like it not wired correctly.
Terry

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 it!

Terry
#6

The wire insulation is very brittle. I can not see how far down inside they might have broken. Is the 7421 the same ohms : 1-2 1042 ohms 3-5 .25 ohms 6-7 .15 ohms and 8-10 363 ohms? I am reading 1-2 920 ohms i need to take off the other leads to be sure. But messing with the insulation breaks. All ready for 1-2 I had to replace the wire to the hole.
#7

Just going "to the hole" when resleeving old transformer leads with brittle insulation isn't enough. You need to remove the bells and slide the tubing as far up in between the insulating paper as you can get it to go.

And don't use any silicone inside the transformer! Silicone will attack the copper and render the transformer toast in very short order.

Silicone should be kept away from vintage radios, period, end of story.

--
Ron Ramirez
Ferdinand IN
#8

Thank you will do
#9

http://www.flickr.com/photos/trog8/sets/...936338219/

Ron you were right, you can see the knot right inside the transformer opening. Also I have some pics showing my readings. If you could look at the pics let me know if I have id the windings correctly. I think with the readings my transformer is good. If you could look at those and let me know that i would be very great full.

Bradley Rush




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