I traded and repaired a Eko Multitone a while back. Apparently it's the firt multi-effect ever.
It has Wah (called Strepitoso in italian), Treble/Bass Booster, Distortion and Repeat (percussion tremolo).
So I traced the 4 different circuits, you can find attached the schematics and some pics.
FS33805 are npn BJT with 1:C 2:B 3:E pinout. I tested one and hfe was 216. BC208 is apparently an equivalent and if i'm not mistaken 2n3904 could do the job.
4JD5E44 is a UJT (maybe equivalent to 2n2646 ?)
I hope I got it right the first time, but if you find anything weird on one of the circuits, point it out and I'll check the board