I can leave it on for a long time and nothing happens.
If something was faulty is should at least show! I thought the issue was before R206 but now I'm being told its after.. There is not much after.. What else can I test in circuit?
If something was faulty is should at least show! I thought the issue was before R206 but now I'm being told its after.. There is not much after.. What else can I test in circuit?
Connections may be fine, but discoloration hadn't appeared out from the blue.
Have you checked the zeners?
Each of the Zeners burns about 0.2W, so they probably should "hover" a bit,
instead of being flat against the board. Their measured DC voltage is ok.
instead of being flat against the board. Their measured DC voltage is ok.
Is this connected to a preamp circuit? How much current should that draw from the supply?
It's much better to use a load resistor first, than a preamp circuit.
It is a preamp!
Assemblage L-1 Tubed Preamplifier Photo #1520871 - Canuck Audio Mart
This is a link to what I got
Assemblage L-1 Tubed Preamplifier Photo #1520871 - Canuck Audio Mart
This is a link to what I got
This is a preamp you bought that does not work? You are troubleshooting a completely built preamp
with an internal power supply?
No sound could be problems other than no HV. Have you measured DC voltages in the audio circuit instead?
Try measuring the tube's cathode voltage for example, it should be just a few volts. Plate voltage should be 100V-200V typically.
There could be an audio output muting circuit that does not work right, for example.
with an internal power supply?
No sound could be problems other than no HV. Have you measured DC voltages in the audio circuit instead?
Try measuring the tube's cathode voltage for example, it should be just a few volts. Plate voltage should be 100V-200V typically.
There could be an audio output muting circuit that does not work right, for example.
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Trust me I did all the basic checks!
The tube glows and everything else is fine! I just need the 250V HV output
Where is states, TO L/C HV and TO R/C HV I should be getting more than 13V which I am not!
After R206 should be 250V right? And the output of the MOSFET should be more than 13V
The tube glows and everything else is fine! I just need the 250V HV output
Where is states, TO L/C HV and TO R/C HV I should be getting more than 13V which I am not!
After R206 should be 250V right? And the output of the MOSFET should be more than 13V
I have given a schematic but I dont think I have permission to share. I can get parts of it!
Thats how I know I should be getting 250V-260V at the MOSFET output. But the MOSFETS are not even getting that power in the first place!!??
Thats how I know I should be getting 250V-260V at the MOSFET output. But the MOSFETS are not even getting that power in the first place!!??
I measure from ground to collector its 250V and from D206 (negative source) to collector and again 250V
I'm betting now that the 2.2 µF capacitor C202 is somehow at-fault. Conducting when it shouldn't be. Not a good conductor, but a resistance-conductor.
Since it is all on a single circuit card, one thing that would help a lot would be to take a nice clear picture of it, and post it. Just asking.
⋅-=≡ GoatGuy ✓ ≡=-⋅
Since it is all on a single circuit card, one thing that would help a lot would be to take a nice clear picture of it, and post it. Just asking.
⋅-=≡ GoatGuy ✓ ≡=-⋅
At this point you should sub a different capacitor to be sure.
Anything close that is 400V will do.
Also ohm out the pcb traces from the 2.2uF to the gates.
Measure from the output lead wire of the 2.2uF to the input lead wire of the 221R gate resistor.
Doing it that way checks solder joints and the pad to trace continuity.
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