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Kegger/blueglow kt88 project

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tubetime said:
Sounds like a shorted capacitor. Disconnect one side of each cap and check.
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I removed both, after seeing I still had 84 ohms I realized that's what the choke meaured, I have double ckecked the caps once removed, charge up on 1K scale, watch discharge on vdc scale. Here is a pic of my wiring without the caps.
 
Squidward said:
I appreciate McGear, but it's probably the last choice for a hobbyist/tinkerer. It'd run fine, and aside from maybe recapping there'd be no reason to touch it. I can't help but want to screw around with my gear, that's half the fun of it for me these days.

If you have to order some caps, get a few .5uF and 1uF, two 5uF, and a 10uF. The goal would be to pad out the voltages you could make from 10uF (what you have now) and 40uF (usual max for a tube rectifier).
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I'll have to order some, I live in a small town, no parts store, I have some caps in a breadboard kit and the audio stage parts but in either case best to order some, Mark at Blueglow didn't add any but not to say my setup may be slightly different, I am assuming my GZ34's are both shot after observing arching. I don't have a tube tester yet.
 
Ground rail is the one with the red with black trace wire going to it. Measure from there to choke leads. Should read open. In previous pic the choke leads where running right under the ground rail and looked like insulation might have been compromised.
 
tubetime said:
Ground rail is the one with the red with black trace wire going to it. Measure from there to choke leads. Should read open. In previous pic the choke leads where running right under the ground rail and looked like insulation might have been compromised.
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6 ohms and 85 ohms

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Squidward said:
Choke should be isolated from the ground. It should have one wire from the C1 / rectifier cathode junction and the other to C2 hot.
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This is what I currently have wired up, at 70 V from the variac it blew the fuse, my last one. I have new caps, fuses, GZ34 and fuses coming on Wednesday.

In the picture you can see the top of the 10uf 630V solen has one side of the choke (is isolated from ground), the other side (Yellow} is hooked to the B+ rail, I had no B+ at the 70V input when it blew the fuse.20190211_121117.jpg

WRONG Pin 8, should have gone to the top of the 10uf cap
 
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tubetime said:
How is the choke isolated from ground when it just read 6 ohms to ground?
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OK, I'm a little slow, however the black wire from the choke is at the top of the the 10uf cap, it does not measure anything to ground, the B+ side of the choke, the yellow wire does read 6 ohms to ground whether the tube is in or not.
 
tubetime said:
It sounds like some part of the choke is going to ground and blowing fuses. I would disconnect both choke wires and then check them both to ground.
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Disconnected the choke, neither side reads anything to ground, if I check the C1 Rectifier junction that is where I pick up the 6 ohms, so when the choke is connected to that , that's where it's coming from

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Take the choke out of the circuit and substitute with a 10 watt resistor of comparable resistance and see if that makes any difference.

Also which cap is the B+ wire exiting pin 8 of the rectifier attached to?
 
Kidmoe said:
Take the choke out of the circuit and substitute with a 10 watt resistor of comparable resistance and see if that makes any difference.

Also which cap is the B+ wire exiting pin 8 of the rectifier attached to?
Click to expand...

It was attached to the 200uf (100/100)
 
I think I found the problem, sigh, removed the mounting and end bell of the power transformer, my rubber grommet was too far in and the bottom of the transformer was pinching the yellow pair and it cut the insulation causing a shot to ground, now I need tp enlarge the hole install larger grommet and reinsulate the yellow leads
 
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