Go for 20 k. Where we were yesterday. We'll get into the channel differences later
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Ok. Seems both channels circuits are ok. Now we found the problem, the grid was floating. Always a learning.
Now, the difference might be tube differences, lets measure your current again. Measure B+, over OPTs, 100 R if you want and over 20/15k resistors.
After that, you can plug in scope and measure ripple before and after 20/15k resistors. That can give guidance on how to best drop that voltage without rising the impedance.
Try also what you started with. Some squarewaves thru the circuit.
Another lession learned: Dont ask whats wrong when your circuit doesnt follow posted schematic😉. We could have found that much quicker. Right?
Now, the difference might be tube differences, lets measure your current again. Measure B+, over OPTs, 100 R if you want and over 20/15k resistors.
After that, you can plug in scope and measure ripple before and after 20/15k resistors. That can give guidance on how to best drop that voltage without rising the impedance.
Try also what you started with. Some squarewaves thru the circuit.
Another lession learned: Dont ask whats wrong when your circuit doesnt follow posted schematic😉. We could have found that much quicker. Right?
The grid floating, the cathode resistor don't grounded, etc I'm a complet disaster, thank you so much for your kind support and patient with me.
Your right channel idle current is 1.8mA? Either something is wrong with the circuit, or the tube is old. Exchange tubes between and measure again. Also, show the measured voltage between grid and ground.
Cool. Your circuit looks like its working, at least the left🙂. Right channel takes way to less current if measures are correct. Check grid leak there again, viltage between grid pin and kathode pin. How much does 15/20k drop?
Habemus XXVI
Then cathode is positive to ground (and now grid also), as it should be. Slow down now. Look, measure and maybe listen to your circuit.