duantro said:Left channel ( from overhead picture view) is dead quiet. Right channel has a slight 60 cycle (and harmonics) hum, even with input unplugged. The lorlin switch wires are there because no matter how much I try to measure pcb's when I get my front panel made, the holes are always a little off. That would be a nice addition for people who make the pcb's to share these exact dimensions. Perhaps my power switch is too close to the extender wires on the far right lorlin? The veroboard on center back is phantom slow start board. Mains transformer is outside of case on the back, 48v transformer is on back right side by power inlet.
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[*]I've swapped output wiring to the other clean output transformer > phase flip switch> xlr, and hum is still present.
[*]I've disconnected the switch board's star ground wiring and buzzed to check for another ground present causing a loop, and nothing.
[*]I've re-flowed solder to any suspect cold solder joints, checked other grounds, and nothing.
[*]I've routed power wiring for left board as far to the rear of right output transformer, no difference.
[*]I've disconnected power to the left board completely, and no difference.
[*]I've disconnected the 6vac to the indicator lamp, no difference.
[*]I've pivoted right choke, no difference
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Anyone have any thoughts on what else to search?
The transformer on the back right is the 48v transformer I assume? I would either mount that on the back if it has leads or move the input and output transformers to the left and away from it. PT let out a fair amount of RF and the audio transformers will pick it up.
Ryan