Not a lot of info on this old pedal, but it was a request so I’ll let Vince tell you about it! :o)
I’ve omitted the reverse polarity protection part of the circuit to keep it more 1590B friendly, but if you do want to add some protection just put a 1N5817 or 1N4001 in series with the 9V supply. The effect includes a buffered bypass and so only a SPDT latching stomp is required, or a DPDT if you want LED indication.
