mwhouston wrote:
I used a 1A rec bridge - 47uf - 470ohms - 100uf - 150ohms - 470uf.
Ah... that will be an issue. Likely that your signal ground is held at one Vd (0.7v to 1.0v) above earth ground (or depending on how your 240 is derived up to 120v above earth ground). This path will also be very low impedance so it can sink LOTS of amps when shorted. This is why you can't use your mains powered equipment.
This is why all those old direct mains powered system only used a single diode in the line side of the feed. This arrangement guaranteed that the ground was at the same level as the neutral.
An input cap on the signal line is not going to fix your problem because the real problem is on the ground side. You need to isolate the mains from your ground connection.
mwhouston wrote:
The total current draw is 89mA and Vg is 20V on the 6L6s. These are well under what Matt thought they would be.
This part confuses me as well. For the low power version I had a 430Ω resistor in the 6L6 cathode and 330Ω on the high power version. For you to have a 20v bias voltage and 89mA of current, this would indicate a cathode resistor value of ≈225Ω. This is far below what I thought was in there.
For reference, here is the schematic I thought I sent to you.
Attachment:
6L6 UL Schematic (low power).jpg
Something more than your power problems seem to be afoot.
By the way... I really like the look of the amp.
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