Quadrovibe high pitch chirping

[rockprocess]

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?

[madbean]

What brand of charge pump are you using?

[rockprocess]

Texas Instruments LT1054CP

[Haberdasher]

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?

[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!

[Haberdasher]

Cool, I just changed out c3 on the little daughter board to 100u so hopefully that does the trick.  thanks

[madbean]

Yes, a 100uF - 220uF will probably do the trick.