How to increase the number of repeats in a PT80?

[theundeadelvis]

I am revisiting an old PT80 build and it works, but I am getting very few repeats (still). If i pluck a note I get maybe 5 repeats. What component can I change to increase this. I realize I may have to make adjustments to quell any run away oscillations. Thanks in advance!

[Mark Hammer]

Spose the "simplest" thing to do is to insert a simple noninverting gain stage before the repeat pot.  Right now, the signal comes out of the compander chip (expander half) and is fed to the recirculation path and the mixing stage, with some passive loss along the way between the compressor input and expander output.  The expander may restore dynamics but it doesn't necessarily restore absolute level if there has been some passive loss between compressor and expander sections. 

Whatever gain a person might add to the recirculation path, it likely wouldn't need to do more than increase the gain by 2-3x to make a big difference in duration of the recirculated signal since there isn't that much passive loss in the first place.  All it needs to do is maintain the signal on expander output at exactly the same level as at compressor input.

Now, whether it will sound listenable....that's another matter.

[theundeadelvis]

Maybe, I should ask, what in my build could be causing the lessened repeats? DId I do something wrong?

[Mark Hammer]

No.  There IS passive loss, or at least many places where it could occur.