Hi all, I know it is a lot of time that this post is not followed but i found an answer to this problem and so i decided to write. She insists you follow Her Rules strictly but if you do, She makes it work every time. If it does not, there is a connection/circuit error in IC2 (and/or IC3 if you did the two-section pot thing). The signal at IC2, pin 6 should show a phase shift which changes at some rotations of the pot. If you noticed distortion at 1V peak on the input, you have a problem with the input amplifier.Ħ. Increase the level of the test signal until you notice distortion on IC1, pin 7, or until you get to 1V peak.ĥ. Trigger on the input signal at IC1, pin 7.Ĥ. Apply a 1kHz test sine wave to the input. Actually, it would be better to use a dual pot and sub one section for each of Q1 and Q2 this will make phase shifts more visible.ģ. Sub in a 100K pot for Q1, hooking up one end contact and the wiper, leaving one end contact open. Quote from: JRB on August 26, 2012, 11:17:12 AMĪt the risk of being pedantic, that one thing will keep you from seeing the problem, even if it's staring you in the face.Ģ. If anyone has any suggestions I would be thank full.

Passes signal but doesn't phase at any point on the resistor (suspect something with the FET's) MXR Phase 90 using the layout from General Guitar Gadgets.Ĭhanged the opamps to more locally available ones and what I had laying around. The strange ting I noticed was as soon as I put the FETs in the sockets the voltage on the Gate gets pulled to the same voltage as the Source. I have looked at the signal with a scope as well and I can see it phase shift it just doesn't modulate even tough the LFO also seems to be working.

Problem is its not producing any phasing sound. After my last failure on the phase 90 with my own layout on perfboard I decided to follow a existing one from General Guitar Gadgets.

Mxr block logo phase 90 schematic