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TonyDuell · 8th May 2016, 5:09 pm

42mA sounds too high to me. And I wonder how on earth it can vary with the setting
of the volume control.

More things to try : Leave the tone control disconnected (open circuit) for the moment/ The set will run without it.

Disconnect one end of C22 (Trader Sheet 732 reference). What anode current (V4) do you measure then? Does it vary with the volume setting?

Measure the voltages (with respect to the chassis) on the junctions of R17-R18, R18-R19. R19-R20, R20-Transformer centre tap. Do these voltages vary with the volume control setting?

8th May 2016, 5:09 pm	#140
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,224	Re: HMV 653 Broadcaster all wave. 42mA sounds too high to me. And I wonder how on earth it can vary with the setting of the volume control. More things to try : Leave the tone control disconnected (open circuit) for the moment/ The set will run without it. Disconnect one end of C22 (Trader Sheet 732 reference). What anode current (V4) do you measure then? Does it vary with the volume setting? Measure the voltages (with respect to the chassis) on the junctions of R17-R18, R18-R19. R19-R20, R20-Transformer centre tap. Do these voltages vary with the volume control setting?