Grab & GoGo Delay/Overdrive

From the post

Here's a cool little dual effect designed by Allesz over on FSB. I actually laid this out a long time ago, but couldn't wrap my head around the switching with the buffer. I've learned a lot since then and feel confident in my understanding to publish this one here. It essentially is a basic PT2399 delay with 2 of the pins from the PT2399 being used as a separate soft clipping overdrive. A simple buffer, built around the MPSA13, is always on, making this a non-true bypass effect. But a little buffering never hurt anyone ;) The original schematic and discussion can be found here.

Since there's a lot of off board wiring going on with this one, here's a full off board wiring diagram to help clarify.