On the plates of the 6V6’s there is 6.8Vrms of 120hz ripple. If I remove the 6v6’s it drops to 4.7Vrms and the hum is no longer audible (as expected).
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With the 6V6’s back in (Russian tubes BTW), switching the bass “IN”, which shorts CH2 and C43, the hum goes away but has no impact on the measured ripple.
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These measurements are made with my o’scope.
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I did some poking through my “inventory” of parts and do not have a suitable choke to swap in for CH2 – still thinking there may be some leakage going on there……?
