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Old 5th Oct 2019, 6:31 pm   #74
Luxman1050
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Join Date: Apr 2019
Location: Margate, Kent, UK.
Posts: 1,728
Default Re: Philips BX281U20 valve radio

Ah nice one I can see where your coming from. Looking at your drawing I definitely have it the right way round. Really appreciate your input and your concerns on the inherent dangers of working with a set like this. As this is the first time I've encountered such a circuit design. But I've learnt something new and hope to continue too with members like yourself Lawrence etc. and as always it's very much appreciated.

Yes I must agree that it's taking me a while to figure out valve designs and how they work which is an education in itself let alone the rest of the components which seem simple enough but are not. But I have my trusted books and tend to do repetitive reading as well as putting it into practice on real circuits. Although funny enough I don't have book that covers this circuit design. One without a mains transformer!!!

I have her on the variac at the moment and she has lit up so what I thought was going to be a complicated trail of elimination just ended up being incredibly dirty contants on mains/volume on/off switch!!!! But I'm slowly winding her up to give things a chance to charge and settle. Hopefully the resistors are fine. Plus I managed to find schematic again with the help of Lawrence which gives the voltage readings around the circuit.

Many thanks Chris
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