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    Building, troubleshooting and testing of these amplifiers should only be
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Old valve radios have any use?

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Hey guys,

Here there seem to be loads of old valve radios for sale, GE etc... for about 15-50 USD.

Do they have any useful transformers I could use? Maybe taps for rectifiers and possibly OPTs?

What kind of currents did the pieces of iron have in those days?
 
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kipman725 said:
There was alot of cost skimping in those days, I have one horific example where the mains choke also doubles as the loud speakers electromagnet.

Common practice in the days before permanent magnet speakers were invented, and in and of itself not an indication of poor quality. I have a very high end Atwater-Kent that used a field coil speaker (1932 vintage) as well as several other psu chokes. Replacing the 2 solitary electrolytics in the receiver was all that was required to get it working again. Oddly enough almost none of the components would be recognizable by modern standards, but all of the metal cased mica and paper caps are good (within tolerance and leakage) and not a single resistor was out of tolerance. Hint - the resistors are not carbon comp - anyone care to guess? And except for a few pieces of wire, the electrolytics, and the missing 56s (4) it's all original. (I was surprised)

Now if the radio doesn't have a power transformer that is a clue, but not necessarily a reliable one of cost cutting. (Radios that had to run on AC or DC mains regardless of cost did not have a transformer.)

Now the AM (MW to those in the UK) only AA5 (All American Five) is a fine example of cost cutting carried to the hilt, they still manage to sound better in many instances than the cheap foreign made solid state radios that replaced them.
 
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interesting that it was common as the radio is in a very nice wooden about 0.5m high enclosure, I had assumed it was not worth fixing and would remain in ornemental duties due to it actualy been a cheap product made to look expensive. Could actualy be expensive :eek:

Problems with I think are broken valves (asin the glass is shattered) will have to see if they are easy to get hold of replacements.
 
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It might well be worth fixing. They have an interesting sound quality (unfortunately I do not have the field coil speaker that should have come with mine) and RF performance that is not too bad in a lot of cases. Just watch out for electrical noise from dimmers and the like.

Mine has IIRC about 10 tubes in it total.. The tubes probably aren't too difficult to find. Just hope it doesn't require a PX25 or similar.
 
for example... so far this is going for about 7 USD..
 

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