I love the fact that the next build is already being planned.

I need more rooms that need amplifiers in them; I've been wanting to build a PP tube amp for awhile but don't have anywhere for it.
 
I love the fact that the next build is already being planned.

I need more rooms that need amplifiers in them; I've been wanting to build a PP tube amp for awhile but don't have anywhere for it.

Rooms are relative, get a higher rack...

PP for power?
 
Rooms are relative, get a higher rack...

PP for power?

For power and a different sound. I have some Heathkit A9C amps in the garage and while the sound isn't as out there in the room as my build of this amp they can be more full sounding.
And it would be fun to try something different. EJ Jurich has a 6L6GC PP design in his book, Vacuum Tube Amplifier Basics, that I'm still hoping to build. I need to sell off some stuff to cover the transformers though.

But I do have to say that as I implement more of the changes from the Kegger schematic to my build of this amp it does handle a wider range of music better. Originally it did really well with Jazz and Vocals but it seems to do pop and rock better too now.
 
For power and a different sound. I have some Heathkit A9C amps in the garage and while the sound isn't as out there in the room as my build of this amp they can be more full sounding.
And it would be fun to try something different. EJ Jurich has a 6L6GC PP design in his book, Vacuum Tube Amplifier Basics, that I'm still hoping to build. I need to sell off some stuff to cover the transformers though.

But I do have to say that as I implement more of the changes from the Kegger schematic to my build of this amp it does handle a wider range of music better. Originally it did really well with Jazz and Vocals but it seems to do pop and rock better too now.

With my existing old Dynaco ST120 I'll notice the difference, Rolling Stones seems too bright and flat, through on so Knopfler or Clapton, Jazzmasters all is in.
 
I am experiencing a ton of problems, all having to do with the power supply. I am experiencing no B+. I have re-wired it several times, tried to have just the power transformer, Caps and GZ34, at 70 volts no B+, if I go above 70 volts on the variac, no B+ plus arching in the tube. I have ordered new caps & tube, and I am almost ready to order a new Edcor power transformer, this is making me sick. Any suggestions greatly appreciated. How can something that appears so simple go so far south..

With nothing else hooked up the transformer seems to read out ok, I did test that also.

Any help, suggestions or advice appreciated!
 
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I am experiencing a ton of problems, all having to do with the power supply. I am experiencing no B+. I have re-wired it several times, tried to have just the power transformer, Caps and GZ34, at 70 volts no B+, if I go above 70 volts on the variac, no B+ plus arching in the tube. I have ordered new caps & tube, and I am almost ready to order a new Edcor power transformer, this is making me sick. Any suggestions greatly appreciated. How can something that appears so simple go so far south..

With nothing else hooked up the transformer seems to read out ok, I did test that also.

Any help, suggestions or advice appreciated!

Post some pics of the guts.
 
Here are some pics, I have removed everything, tested the transformer and reassembled, still no B+

20190209_132422_resized.jpg 20190209_132445_resized.jpg 20190209_132501_resized.jpg 20190209_132517_resized.jpg 20190209_132529_resized.jpg 20190209_133438_resized_2.jpg 20190209_133449_resized_2.jpg 20190209_133502_resized_2.jpg

This is what I measured with just the transformer:

120 VAC input

Brown Pair = 7.4 VAC

Yellow Pair = 5.6 VAC

Red/Black & one side red 408 VAC

Red & Red = 806 VAC
 
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OK, first things first, you're doing great, and nothing looks unrecoverable here. Nice looking work, in fact!

When I built my first KG-88, I had a problem where my voltage dropped right after start-up, and I thought I had everything wired correctly. I was distraught, and I took it to the man himself. Keg ended up upping the value of my first cap 1uF at a time, and it eventually responded correctly and he was able to dial in the final voltages by tuning that first cap.

What is the value of your first cap? Do you have a first cap? I looked for your PS schematic, didn't see one.
 
OK, first things first, you're doing great, and nothing looks unrecoverable here. Nice looking work, in fact!

When I built my first KG-88, I had a problem where my voltage dropped right after start-up, and I thought I had everything wired correctly. I was distraught, and I took it to the man himself. Keg ended up upping the value of my first cap 1uF at a time, and it eventually responded correctly and he was able to dial in the final voltages by tuning that first cap.

What is the value of your first cap? Do you have a first cap? I looked for your PS schematic, didn't see one.

The only caps are the Solen 10uf 630V and the F&T 100/100uf 500V, I am thinking of taking the caps back out to show the wiring under them.

Yesterday I eliminated even the switch, heater wiring, thermistor, still no B+.
 
All wiring looks correct. Check resistance form B+ to ground that may point towards a bad cap if resistance is not very high. Think you are right in thinking a cap or rectifier tube. Transformer looks good with those readings.
 
All wiring looks correct. Check resistance form B+ to ground that may point towards a bad cap if resistance is not very high. Think you are right in thinking a cap or rectifier tube. Transformer looks good with those readings.

84.4 ohms B+ to ground, no tube.
 
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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