Was there a version of the LPB-2 in the 70s with a board inside or were they all PTP like this one?

You’ll see both.  I have a Sreaming Tree that’s done PTP and an LPB-1 with a tiny circuit board.

The links in your sig don’t work.

I have one of those. Just picked it up at a junk store for $20! However, it seems to be not working properly. I has a low output and is distorted, with no variation in the distortion.

Any ideas on what to check to fix it? My guess is one of the capacitors is dead.

Any help is appreciated.

Thanks.