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Help - 807 Technical problem

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lcsaszar

lcsaszar

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Joined 2004
Alastair E said:
330 ohm looks quite reasonable for the 807/6l6 types
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Hm, I also tried cathode bias, the resistor was 560 ohm 5W (ceramic case), bypassed with 2 x 10uF 250V WIMA MKS-4, so I got around 50 mA. Then I converted the circuit to fixed bias: cathode tied to ground (through the 3 ohms or so current monitoring resistor) and applied negative voltage (between -35 and -40V) on g1. The reason is that I wanted to eliminate the bypass capacitors.
 
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