Practical Electronics Fuzz Pedal
I built a few effects from designs and kits in magazines like Electronics Today International, Practical Electronics and Everyday Electronics. I used to buy Elektor too but there were always fearsome lists of errata in their pages referring to previous designs and I was never totally confident. The pre-amp used in the troublesome bass combo mentioned elsewhere was one of their designs.
The fuzz box gets a mention as it worked really well and I carried it around with me everywhere - you can hear it on Invertebrates I believe, in conjunction with a phaser which had a similar diecast metal case and was probably designed by the same person.
I had an opto-electronic compressor too which didn't really do much for me or my sound. I also thought it was a bit retro as VCA designs were just coming in. Of course opto designs are all the rage again now…
I tried to adapt and design new effects from these starting points but mostly these turned out badly. One attempt was an auto-panner using two opto-compressors as gain modules with a low frequency oscillator driving the leds. The thing ran off a multiway cable carrying signal in, stereo signal out, and bipolar power supply through a seven pin DIN connector. The switching of the leds caused terrible interference from the power lines onto the signal lines. Another design classic.
A stereo phaser running off batteries was more successful.
I can't recall what happened to these pedals, most probably they were in the jumbo bass case which I'd built to contain the full rhythm section - Columbus Jazz Bass and Clef Drum Machine - that was stolen from The Lancaster Music project some time in the early 80s.