Author Topic: Ancient old Radio's: worth Restoring ?  (Read 7118 times)

Offline Steerpike

Re: Ancient old Radio's: worth Restoring ?
« Reply #15 on: April 17, 2012, 08:18:11 PM »
I suppose I am unlikely to ever get one of those so I have toyed with possibly by-passing the audio stage with a simple IC audio amplifier.

One could do it with an IC, but so much nicer to use a valve - even if a modern one. If there's enough 'height space' one could make an adapter using the broken valves base, and put an octal or noval socket on top. If the filament supply is AC, it's possible to rectify & filter that to get close to the 6v3 needed by the ECC types or a 6SL7/6SN7/6SC7

Online Family_Dog

Re: Ancient old Radio's: worth Restoring ?
« Reply #16 on: April 17, 2012, 09:14:06 PM »
There is space above the chassis for this, not too much below the chassis, but also not impossible if using a B7G or B9A based valve. The E438 valve with a blown filament looks perfect - almost new - such a pity the filament has gone. I did find one available in NZ a few years ago but the remaining valves are very weak, obviously original ones that came with the radio. If memory serves me right, my AVO CM measured them at around 15-20% efficiency, so I never bothered bringing the valve in. Would have set me back about R100 at the time to do so.


-F_D



-Eric

That Guy in South Africa...
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