The quadrovibe I just build sounds great except for the high pitch chirping that matches the effect speed. I suspect it has something to do with the DC power filtering; I'm using the charge pump board that was included in the quadrovibe document. It also goes away when I switch to battery operation. Any ideas how to ditch the annoying chirp?
What brand of charge pump are you using?
Texas Instruments LT1054CP
I'm having about the same issue as well using ti lt1054cp, sort of like a high pitch noise that fades in and out simultaneous with the pulsing of the lamp. I was hoping it would get better once I boxed it up but I haven't done that yet
Is your qvibe in an enclosure, rockprocess?
Yes, mine is boxed up. I got the problem fixed though by replacing out one of the 10uf caps in the 18v side of the charge pump with a much larger cap 500 uf. Chirp is completely gone. I'm not sure if this was overkill but it fixed it using parts I had on hand. Thanks!
Cool, I just changed out c3 on the little daughter board to 100u so hopefully that does the trick. thanks
Yes, a 100uF - 220uF will probably do the trick.