Thank you. With all the new regulations being put into law there is about nothing a person can do these days. They demand a safety ground be wired into a simple preamp, so that anyone who might be inclined to put aluminum foil around a fuse in the case of a failure might be electrocuted. I think you can understand how I might be somewhat frantic after several months of chasing down hum. I hope, anyway!
No, safety first and grounding tube gear cases to PE is no joke. It is to protect the users. If your audio GND isn't done right you have hum. There are several ways to solve this.
If you are in a country where audio GND is connected to PE directly in every device I would start there.
If you are in a country where audio GND is connected to PE directly in every device I would start there.
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An externally hosted image should be here but it was not working when we last tested it.
I am working on this circuit, and I have replaced the 100 ohm resistors with .047uf 600v polypropylene caps. Now the light doesn’t work. How could I get it working without putting him back in the output of the tube?
I am working on this same circuit again, and I have replaced the 100 ohm resistors with .047uf 600v polypropylene caps. Now the light doesn’t work. How could I get it working without putting hum back in the output of the tube? The same schematic is shown in post no 1, but I also eliminated the ground elevation circuit with the 470kohm and 82kohm resistors and the cap.
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This is the circuit I’m copying. I take two mic inputs, so I’m using both side of the tube. The relay pushes more voltage to the plates and operates the light. There are two possibilities for plate voltage, one green, one red. I don’t know how to upload the actual schematic for what I’m working on with my phone.
This is the circuit I’m copying. I take two mic inputs, so I’m using both side of the tube. The relay pushes more voltage to the plates and operates the light. There are two possibilities for plate voltage, one green, one red. I don’t know how to upload the actual schematic for what I’m working on with my phone.
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