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AlanC · 23rd Jun 2012, 3:35 pm

Mmm, as the 6K7G would be cut off at that wouldn't it; hence the lack of IF? Didn't spot that! Yet the oscillator grid, at -9v wrt the cathode, looks good...

R3 is the common cathode resistor; but the value appears to be 15K according to the circuit, though its a bit difficult to read. That's a bit bizarre; I would have expected a couple of hundred ohms??

Malcolm, what value is R3 in the radio? Does it measure the correct value?

Also, please tell us what the common cathode voltage is with the 6K7G pulled, and the 6K8G. With both valves pulled, there should be zero volts.

23rd Jun 2012, 3:35 pm	#12
AlanC Hexode Join Date: Jul 2006 Location: Sheffield, South Yorkshire, UK. Posts: 312	Re: NAAFI receiver problem Mmm, as the 6K7G would be cut off at that wouldn't it; hence the lack of IF? Didn't spot that! Yet the oscillator grid, at -9v wrt the cathode, looks good... R3 is the common cathode resistor; but the value appears to be 15K according to the circuit, though its a bit difficult to read. That's a bit bizarre; I would have expected a couple of hundred ohms?? Malcolm, what value is R3 in the radio? Does it measure the correct value? Also, please tell us what the common cathode voltage is with the 6K7G pulled, and the 6K8G. With both valves pulled, there should be zero volts. __________________ Always expect the unexpected...