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#135965 03/11/03 11:24 AM
Joined: Aug 2001
Posts: 7,520
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I second Sven's comments there. Even if I get an old radio which is way beyond reasonable repair, there are still parts likely to be worth salvaging. (Have you seen the price of new tuning condensers these days, even if you can locate the type you want?)

You may well be able to find a suitable working xfmr in another old set which is not worth repairing and make use of it, although the mchanical mounting and spacing arrangements may need a little ingenuity.

By the way, which winding of the xfmr is gone? Primary, LT, or HT?

#135966 03/13/03 02:57 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Trumpy Offline OP
Member
No Paul,
It's the HT side and the Heater Circuit.
One saving grace, here, I bought the radio off of the guy, and before I ever worked as an Electrical Apprentice, I worked for a Motor/Transformer Rewinders, I've still got all of the charts and Formulae, from there.
I was just an after-school boy, who uesd to help out with rewinding coils, Xformers and Motors.
Not my cup of Tea, being locked up in a workshop all day.
I'll fix this one up, in my own time!. [Linked Image]

#135967 03/15/03 06:06 AM
Joined: Aug 2001
Posts: 7,520
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Member
Both the HT and filament windings are open?

Sounds like a fairly drastic failure. The xfmr could have expired by itself, but I'd check for shorts or other problems before trying to fire up with a replacement.

One item to check carefully, especially if the set has been unused and in storage for many years, is the reservoir capacitor. They can sometimes go off with quite a bang when HT is suddenly applied after all that time!

By the way, you mentioned 4-tube plus rectifier at the top of the thread: What rectifier valve is fitted?

#135968 03/15/03 11:13 PM
Joined: Jul 2002
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Likes: 3
Trumpy Offline OP
Member
Paul,
I am well aware of the risks associated with Reservoir capacitors, I was well warned about them, by my Father, I have always heeded his advice.
With respect to the Rectifier valve, it was the only valve in the set, that did not have much dust on it, but it must have been pretty hot, as it had lost all of it's markings, apart from a very faint GE logo.
Hope this helps, Paul. [Linked Image]

#135969 03/16/03 07:03 PM
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I was curious mainly as to what tube might be fitted. After you found two 12AT7's in there, I was half expecting you to come back with a number which isn't actually a rectifier!

#135970 03/19/03 03:32 AM
Joined: Jul 2002
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Likes: 3
Trumpy Offline OP
Member
Paul,
There's no need to be cheeky!.
All I gave you, was what I had in front of me!.
I guess I will never know the numbers off of that valve, it's gone.
Don't worry there, mate, I am not annoyed, just a bit sad that there was no code on the Regulator valve. [Linked Image]

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