This is a circuit from a 1977 documentation. R1 is 39k, R2 15k, R3 3k9 and C1 uF. The tube is the critical component of the project.
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This is a circuit from a 1977 documentation. R1 is 39k, R2 15k, R3 3k9 and C1 uF. The tube is the critical component of the project.