Hi all. I recently cleaned up and installed a true bypass on my '75 phase 90. I cleaned out 40 years of melted foam in the process. Well something I did pissed it off because it isn't phasing very well anymore. Everything works fine except the depth of the phase doesn't seem to match what it used to. And when its on the slowest setting I can't even hear a difference in tone. Highest speed seems to at least tremolo with minimal phase shifting. The volume is the same with the effect on or off. Theres 9.5v going into it. The diode is working fine. I checked c15 to see if it was open and its fine. The bias trimpot has 5v going into it and 2.5v going out which seems good. I checked all of the voltages that are listed on the http://www.generalguitargadgets.com/effects-projects/phase-shifters/mxr-phase-90-script-logo/ instructions. Most everything looked about normal except: Pin 6 on IC2-IC5 is 5v on my unit and apparently it should be 2.1v. Pin 6 on IC6 goes from 1.8v to 8v on mine. Instructions says 4v. Not sure if this is normal. The only other thing is the collector on Q5 is 3.2v on mine and instructions says 4.3v. Sorry for the long post but I wanted to try and cover everything I could. I really appreciate any help!! Thank you!