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Luxman1050 · 17th Oct 2019, 6:17 pm

Cheers guys thanks for working out the math bit lost on that one I'll have a look in one of me books there all full of calculations but related to amps not radios. Okay so Lawrence saying in series with R37 but Herald saying R39! So which is best option R37 seems logical whereas R39 is slightly up the chain where the voltage has already dropped. Or does it not matter?

I'll have to fit that resistor underneath somewhere not sure where quite tight in there. No room for it ontop side.

So I did not need the heater volts as they where always going to be high. So not sure why I was being asked for them? Ha.

So question is why is pin 8 on the last UCH21 going to negative on pot and negative to C75? Whereas all others are in series? Must be a reason.

Cheers again Chris

17th Oct 2019, 6:17 pm	#123
Luxman1050 Octode Join Date: Apr 2019 Location: Margate, Kent, UK. Posts: 1,728	Re: Philips BX281U20 valve radio Cheers guys thanks for working out the math bit lost on that one I'll have a look in one of me books there all full of calculations but related to amps not radios. Okay so Lawrence saying in series with R37 but Herald saying R39! So which is best option R37 seems logical whereas R39 is slightly up the chain where the voltage has already dropped. Or does it not matter? I'll have to fit that resistor underneath somewhere not sure where quite tight in there. No room for it ontop side. So I did not need the heater volts as they where always going to be high. So not sure why I was being asked for them? Ha. So question is why is pin 8 on the last UCH21 going to negative on pot and negative to C75? Whereas all others are in series? Must be a reason. Cheers again Chris