help, my bi-phase isn't working

[schizophonic]

I just acquired a mu-tron bi-phase that was working when I got it. I opened it up to see about replacing a broken pot. I closed it up without replacing anything, and now it passes a signal whether bypassed or not, but I don't get any phase. Did I fry something? How can I best go about diagnosing the problem? thanks for your help!

[gorohon]

While in process of removing the cover did any wires get moved at all?  Check the wires and conections for continuity with a DMM.  This kind of crap happens to me all the time because I'm always taking things apart and putting them back again.

[puretube]

http://filters.muziq.be/model/musitronics/biphase