Looking for a Hilgen Champion schematic !

[FUCHSAUDIO]

I have one in the shop (the PC board version), and can't seem to find the cause of a horrid hum problem.
If anyone has a schematic they can e-mail or upload, it'd be appreciated.

Thanks !

[Stevem]

Is it flowing down the preamp string, or only in the output stage?

Bias supply hum?

I had a fender HD last year that had the same deal and I did not see any sign that the first node filter was bad, yet after testing all the tubs, then yanking them all out but for the outputs for the hum coming from just the output section sent me back to jumping out that first node filter, and bingo that was it!

After 40 years of trouble shooting amps, why I did not go there first that time around I can’t say,lol!

If it has any SS / IC sections then one of them could be shorted and dumping DC into the audio stream, or a shorted blocking cap in such a section .

[FUCHSAUDIO]

It's all tube. Looks like a 7199 is being used as part of a reverb circuit and one side might be a mixer ? I nulled the heater line with a balance pot, so idle is now quiet, actually silent.

Here's the issue: When you turn up either channel, you have a "hard" 120 hz hum, sounds like a ground loop or bad filter, but if I add a cap to the cathode of one side of the 7199, it fully goes away. Problem is, it rolls off the high end.

Looks like a 12AX7 cathode feeds the 7199 cathode at that junction, so I'm thinking it's some kind of a mixer via the cathode as an input. Only 42 volts at that plate, which seems pretty weird. The customer supplied another 7199, but it's a noisy mess and unusable. Looking around the shop to see if I can find another to eliminate the tube. It's bizarre, two other techs gave it back unrepaired, so it's become someone of a mercy f*ck for me..a challenge of a certain order. A schematic could open up a whole lot of mysteries...

[Stevem]

What’s the value of that plate resistor on that 7199 and what’s the V+ on the power supply side of that resistor with the tube out?

Does the noisy as hell tube test ok for GM and if so what is the plate voltage is seen with that tube in the socket, the same 42 volts?

Looks like build wise on that 7199 that pin 8 is the cathode for triode section and pin 6 is the cathode AND grid 3 for the tubes Pentode section.

So which cathode of the 7199 is getting fed from the cathode of the AX7, the triode section or the pentode?

Also maybe the darn board has become conductive?

[sonicmojo]

I've got a Hilgen Champion, I'll try to dig out the schematic, I think I had one at one point. Mine is older maybe, point to point, no boards. Hopefully I can find my rough drawings that I had that I got somewhere. There is also hilgenamplifiers.net.

[sonicmojo]

Hope this helps. I got this years ago and don't remember where and can't vouch for accuracy but I just scanned in the printed copies I had made. Let me know how it goes. I also had a Pacesetter until last year which was the same circuit in a combo. Great amps (at least the non PCB ones I have had)

[SoulFetish]

We've got a longtime customer who loves Hilgens, so we've had several come through the shop.
If you have trouble finding a 7199 that isn't noisy as hell, you can get a socket adapter and use a 6U8A in it's place (or rewire the socket). They are more affordable, available, and seem to be much more stable in my experience.

https://www.tubedepot.com/products/6u8-to-7199-adapter

[FUCHSAUDIO]

Hope this helps. I got this years ago and don't remember where and can't vouch for accuracy but I just scanned in the printed copies I had made. Let me know how it goes. I also had a Pacesetter until last year which was the same circuit in a combo. Great amps (at least the non PCB ones I have had)

This was very helpful !! Thanks, I'll keep you guys posted.

[FUCHSAUDIO]

Thanks for the assist. Got it sorted out and happy. It helped to see some idea of the reverb/mix stuff. Reminded me somewhat of the Fender outboard reverb dry mix from cathode to cathode, but it's quiet and happy.

[sonicmojo]

Thanks for the assist. Got it sorted out and happy. It helped to see some idea of the reverb/mix stuff. Reminded me somewhat of the Fender outboard reverb dry mix from cathode to cathode, but it's quiet and happy.

Glad to help! The only gripe I have with mine is it is a little dark sounding. I tend to keep the tone control on 10. I may have to go in and tweak a couple of cap values.

[FUCHSAUDIO]

This amp is a bit dark sounding too. I raised the value of that resistor between those two cathodes (it's the dry-mix resistor) which reduced overall gain of the amp and increased the available reverb at a lower setting of the reverb pot. The amp had plenty of gain when I was done and lower noise too. Previously, you had to raise it pretty high and the pan was close to feeding back. If you raise that value high enough, (I think I ended up at 24-K , up from 10-K, maybe ?) you could add a cap across it...maybe adding a presence cap on the FB loop ? There are a few ways to skin that cat.

[JerryFJA]

Hope this helps. I got this years ago and don't remember where and can't vouch for accuracy but I just scanned in the printed copies I had made. Let me know how it goes. I also had a Pacesetter until last year which was the same circuit in a combo. Great amps (at least the non PCB ones I have had)

That was from me! I love those old Hilgens!