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Old 10-20-2006, 06:21 AM
RetroHacker RetroHacker is offline
Electronics Accumulator
 
Join Date: Jan 2005
Location: Niskayuna, NY
Posts: 464
Keep in mind that since you've recapped the set with modern capacitors and replaced resistors with modern ones, that your radio is probably more in-spec than it was when it was new. Those old components were like +/- 20% or worse. Replacing the filter caps with higher ratings is good - helps reduce hum. But once you do find a schematic with voltage ratings on it, trying to get your set to match is going to be hard - you can't always trust old numbers! That was done with a VTVM and with original +/- 20% components. So if you find the voltages in an old manual, don't try to get them exactly - as long as you're close it doesn't matter. As for you B+, it sounds about right for a table radio like that - and all the tubes are meant to operate at that voltage. I don't have a K731, if I did I'd measure it for you. It looks like that radio is covered in Sam's 653-12. Try to see if your local library has it, or maybe someone here has it and can send you scan. Having the schematic is really useful.

Have fun - and try not to drive yourself too crazy getting things exact - with these kinds of electronics, exact is always going to be +/- 20% <grin>.

-Ian
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