Electro Harmonics Pulsar Tremolo

Here’s the original EHX Pulsar trem from the 70s (not to be confused with the modern Stereo Pulsar EHX manufactures today). It features Intensity and Speed controls as well as a switch to go between a hard and soft wavefrom. Original units often suffer from clock bleed from the LFO section. So I’ve drawn a second layout with mods to try and fix it. The 470Ω resistor above the IC and the 47µ cap below Q1 should be tweaked to find the values that work the best. Pots can be board mounted from the solder-side using right angle PCB pots.

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