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Neil Purling · 12th Jul 2006, 8:20 pm

I get between 125K and 150K depending on whether the value of the HT is 250V or nearer 300, for 2mA current flow.
I copied the design of the amplifier circuit from my 1952 edition of Radio for Boys. I believe Hunts Smoothing Bomb did the same.
The AF stage of both our sets is from the 'AC Mains Superhet'. This uses a EBC33 Double-Diode Triode for AVC, detector and audio pre-amp driving a 6V6. Me and H.S.B both substituted a 6J5 for the triode part of the EBC33.
Any further opinions on whether the 6J5 is biased correctly or not, according to the diagram with this thread?
If not, then what is appropriate?

12th Jul 2006, 8:20 pm	#14
Neil Purling Nonode Join Date: Jul 2005 Location: Hull, East Yorkshire, UK. Posts: 2,085	Re: Regarding home made TRF I get between 125K and 150K depending on whether the value of the HT is 250V or nearer 300, for 2mA current flow. I copied the design of the amplifier circuit from my 1952 edition of Radio for Boys. I believe Hunts Smoothing Bomb did the same. The AF stage of both our sets is from the 'AC Mains Superhet'. This uses a EBC33 Double-Diode Triode for AVC, detector and audio pre-amp driving a 6V6. Me and H.S.B both substituted a 6J5 for the triode part of the EBC33. Any further opinions on whether the 6J5 is biased correctly or not, according to the diagram with this thread? If not, then what is appropriate?