I'm having difficulty with Grounded Grid high voltage postive supply. The transformer buzzed so I assumed it was a short.
The transformer is a handwound toroid with a 12V and dual 120V secondaries (over 900 bifilar turns!).
I connected the transformer to the power supply alone (DC not connected to anything) and the voltage I saw was way above 200V, somewhere between 250 and 350, for both sides.
When I first connected the power supply to the rest of the circuit I discovered that I had miswired the HV power supply and it was blowing the AC fuse. I fixed the wiring and the negative supply began working perfectly while the postive supply made the transformer buzz but did not cause the fuse to blow.
I know it's the postive side because there is no transformer buzz with the negative HV and 12V supplies both connected.
So now I have everything unwired and tried swapping secondaries to no affect. The postive supply (right side of linked image) now only puts out 160V into no load and makes the transformer buzz. I've never built anything from a schematic so I'm at the bleeding edge of my abilities.
In linked image, AC connects to the negative supply at the junctions of D1/D2 and C4/C5 producing the correct voltage of -200V at the junction of C7/Z1/R16 when connected to the rest of the circuit.
I measured the resistance between D3/D4 and C8/C9 and it measures infinite. The resistors measure correctly.
I imagine that my miswiring of the supply that blew the fuse may have helped fry something (cap, diode?) but I'm not sure how to verify. Any guidance greatly appreciated! Thanks.
The transformer is a handwound toroid with a 12V and dual 120V secondaries (over 900 bifilar turns!).
I connected the transformer to the power supply alone (DC not connected to anything) and the voltage I saw was way above 200V, somewhere between 250 and 350, for both sides.
When I first connected the power supply to the rest of the circuit I discovered that I had miswired the HV power supply and it was blowing the AC fuse. I fixed the wiring and the negative supply began working perfectly while the postive supply made the transformer buzz but did not cause the fuse to blow.
I know it's the postive side because there is no transformer buzz with the negative HV and 12V supplies both connected.
So now I have everything unwired and tried swapping secondaries to no affect. The postive supply (right side of linked image) now only puts out 160V into no load and makes the transformer buzz. I've never built anything from a schematic so I'm at the bleeding edge of my abilities.
In linked image, AC connects to the negative supply at the junctions of D1/D2 and C4/C5 producing the correct voltage of -200V at the junction of C7/Z1/R16 when connected to the rest of the circuit.
I measured the resistance between D3/D4 and C8/C9 and it measures infinite. The resistors measure correctly.
I imagine that my miswiring of the supply that blew the fuse may have helped fry something (cap, diode?) but I'm not sure how to verify. Any guidance greatly appreciated! Thanks.
An externally hosted image should be here but it was not working when we last tested it.
What diodes are you using? I had some UF4007 go short circuit on me once...
Otherwise, try a process of elimination?
Otherwise, try a process of elimination?
I'm using 4007 something.
After staring at the picture some more this morning, I'm going to look at the zeners when I get home tonight.
If I can't figure anything out, I'll just order more parts from digikey and rebuild it. I know I have the wiring correct. I've updated the picture so it is more clear where ground, DC, and AC connect: picture
After staring at the picture some more this morning, I'm going to look at the zeners when I get home tonight.
If I can't figure anything out, I'll just order more parts from digikey and rebuild it. I know I have the wiring correct. I've updated the picture so it is more clear where ground, DC, and AC connect: picture
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