Re: The "Sussex" Homebrew Valve Tester.
The X-Ray diagram referred to in post 282 shows the cathode of D6 connected to the junction of R19 and R20. This is, as reported not as shown on the circuit diagram. However in my oscillator complete stability is obtained by connecting D6 the wrong way round according to the circuit diagram, the cathode should be connected to the junction of R19 and R20 with the anode connected to C6 and R17. The purpose of this diode has always puzzled me because it is not needed in the conventional phase shift oscillator. I would be interested to know the results obtained by other builders if they reverse this diode, i.e. place it the opposite way round to the circuit diagram.
Barry G4CTU
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