SVT power supply question

[Randall]

SVT-HD limited edition, same as previous thread. I don't find an exact schematic, so I am working from the service manual. Couple of questions, mine has a single 40uF can (represented as C12B) positive not connected to the junction of the two 220K resistors and C10 and C12A, but rather to the floating neg of 30uF C11. I don't think it is a mistake, because most everything looks original, and there is no long wire that would be needed to get there, or physical spot on the board for it to connect to. So, does this make sense? If so what would it accomplish?

Also, not shown are 100K 1% resistors across 40uF C12C pos to gnd tab, 40uF C12B (single can) pos to gnd tab, and 30uF C11 pos to floating gnd tab. What are these for?

Also, all the cans that have ground wires are 10R above chassis ground, and I see nothing about that either. All cans are twist lock onto insulators, and are not making chassis contact. I will have to rig the single 40uF with a 1" clamp because it is not a twist lock, but I will make sure it is insulated.

https://ampeg.com/support/files/Sche...Schematics.pdf

[The Dude]

The two 100K sound like a second totem pole arrangement. They are just trying to use all of the sections of the can caps to best advantage considering available voltage rating and capacitance. You/We might be able to better understand it if you draw it up.

[The Dude]

Your supply is probably closer to this one, although they might use "close enough" cap values and parallel or series caps to get the filtering needed and meet voltage requirements. Also notice the "dual ground" configuration.

https://ampeg.com/support/files/Sche...Schematics.pdf

[Randall]

Yes, some of it is more similar, some of it less so. And I do now see the 10R resistor at the input jacks between the two ground points. I guess in the end, wiring it as it arrived should be safe enough.

But man, flipping this beast on my bench repeatedly is such a pain, not to mention getting it in and out of the box.

[The Dude]

Yes, some of it is more similar, some of it less so. And I do now see the 10R resistor at the input jacks between the two ground points. I guess in the end, wiring it as it arrived should be safe enough.

But man, flipping this beast on my bench repeatedly is such a pain, not to mention getting it in and out of the box.

Yep,...... beast is an apt description! You can skip the gym for a while.

[DrGonz78]

Yup if you didn't have a hernia before it arrived, you might now.