One of the largest sites for do-it-yourself guitar effects builders. Schematics and Printed circuit board layouts for rare pedals like the Tycobrahe Octavia, Clyde McCoy wah and lots of vintage fuzz pedals!
The M-104 MXR Distortion + aka Distortion Plus aka D+ is a distortion guitar pedal designed by MXR and released between 1978 and 1979. The original stompbox did not have external power jack or indicator LED. Jim Dunlop bought the MXR licensing