Nah... Unfortunately I dont own a scope. A friend of mine has got one, but we dont really know how to use it🙂
Pin 9 is the screen voltage. If your plate volts are stable but your screen volts dropping, you need to check that 100 ohm resistor. They can get fried if not high enough wattage rating, and may have been damaged if a bad tube or previous wiring problem. Screen voltage variance like that would explain your volume dropping out momentarily. What is the present resistor rating?
I would suggest checking them to make sure. If one is giving problems you may get that buzzy sound and lower volume problem.
They seem fine... Both read 99 ohms...
Some guys suggest installing a 5 k 5 watt before the two 100 ohm resistors?
Not that they have my problems...
But some guys Think this should be helpful, and keep the amp more stable...
Some guys suggest installing a 5 k 5 watt before the two 100 ohm resistors?
Not that they have my problems...
But some guys Think this should be helpful, and keep the amp more stable...
Worth a try, and if you have access to another power tube as well may be worth trying too. I am still trying to figure out the variance in glowing on the tube. Double check your bias and maybe decrease it a bit? just suggesting.
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