5E3 problem - New poster, need help

[jrdamien]

Built a 5E3 with a larger pt and ot, nothing special or odd. But the standby is leaking. On standby the caps are getting 18v, 16 and 14, with 18 on the standby. If I disconnect the downstream from the switch, no dc on the switch or the caps.

In addition, I am getting a lot of scratching on the guitar pots, which suggests I am leaking dc. But I have moved the grid stoppers from the jacks to the sockets, no change. Checked and changed the coupling caps. No help. Tried 3 different grounding schemes. All the same.

Any help would really be appreciated.

[loudthud]

What is the plate voltage (pins 1 and 6) of the first tube when the standby is in play mode? What is the cathode voltage (pins 3 and 8) of the same tube?

[jrdamien]

What is the plate voltage (pins 1 and 6) of the first tube when the standby is in play mode? What is the cathode voltage (pins 3 and 8) of the same tube?

Of v1:

p1: 64
p2: 72
P3/8: 0

Standby switch problem solved. Removed 100k 2w resistor per Ceriatone's layout and swapped wire going to board.

DC leakage still a huge and annoying problem.

[loudthud]

Of v1:

p1: 64
p2: 72
P3/8: 0

Those plate voltages are too low and put the tube into "grid leak" territory. Why is the cathode voltage zero? There should be an 820 ohm resistor to ground making the voltage about +1.5V.

[jrdamien]

This I do not know. It's actually more like .40. But that's not what I'm trying to figure out right now. I'm just trying to get rid of the scratchy pots on the guitar (as caused by the amp).

[loudthud]

"Grid leak" territory means that the plate voltage is too low causing current to flow out the grids where it causes your guitar's pots to scratch. Get the cathode voltage up to 1.5V, the plate voltages should go up to about 150V and you pots will be silent. The voltage on the third filter cap needs to be about +250V.