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Philco model 70 rebuild - by Tim P.
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Hello all! I finally have the 70 chassis on the "bench". I thought it might to be interesting to parallel Mike on a restoration, having 2 radios being rebuilt at the same time and comparing notes. Heres my story. This will be my first attempt at a full rebuild v.s. a repair, and this is the oldest I have ever attempted. It has been a lot of years since I have worked on anything tube, but I have dusted off the old testers and Riders books, gotten my glasses , notebook and am ready to tackle this.

The radio looks largely undesturbed and clean. I only found one cap that has been replaced. There's a LOT of room under this thing! Much better than those cramped electronics I used to repair! The previous owner told me that the radio powered on, had a low hum and had static. I havent powered it on yet. I am going to check some things first, like the coils, resistors, and will replace the electroytic caps in the power supply. If things check out, I am going to power it on with a variac and "see what I have".

I am sure some will tell me to replace all the caps and test the tubes, etc. But, I want to see whats there first, and that may help prevent me from "causing" a problem while rebuilding. If it worked to some degree before I replaced a part, then suddenly stops, or has a new problem when I test it, I can stop right there and track down the problem, rather than try to figure it out after a full rebuild ... oh-no, what did I do???

Heres a couple of shots of the start of this adventure. I am sure to many this will be a familure sight.
   
   
I suspect this is an early model, but I am not sure. The number stamped on the rear of the chassis is: 433317, and the sticker on the tube shield calls it a model 70, 70A, 270, 270A, 370, 370A. Any input and advice is welcome, as is any advice as to what to look for that are common problems and failures.

Thanks all!

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Philco model 70 rebuild - by Tim P. - by TV MAN - 01-29-2014, 11:46 AM



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