Klon Centaur Question

[midwayfair]

that's actually just a radio shack project box. they're a little bigger than the hammonds, but easier to work and lighter weight, sheet metal instead of cast.
do you have radio shacks in israel? i dunno if they've made it out of this country or not, but the price is right, about 3.49 a piece and free shipping if ya order 50 bux worth.
they're fine for most purposes, and can stand up to my 330lbs ass stompin' on 'em... so...

I'm trying to fit this circuit into a 125b, though I haven't managed to make it work on my proto-board. I only get weak signal..

Keep at it. Klones will fit in a 1590A with the right layout:

[tubesimmer]

If you mean the path through R19, it's not positive feedback, the signal from the first stage goes through the R7/C16 filter which lets through frequencies below about 100Hz then through C19 into U2A.

Apologies for the resurrection, I'm just building one & working out the schematic. Frequencies below 100Hz would be low G to E on the 6th string. Is it more likely that C16 is just acting as a common AC ground point for R7 and R19? That's how I'm reading it.