AquaboyDX Question

[mcasemo]

I'm troubleshooting my Aquaboy Deluxe 2013 build, not yet ready to post a tech help post yet.   Short story, I have high pitched noise, thought it was clock noise, but after removing all the chips its still there.   

The weird thing is that it still passes dry signal, although a bit reduced, with all the chips not installed.  Is that possible?  Just wondering if that is what i should be troubleshooting now.  There is a transistor buffer before the LF353 buffers, could it push signal through the feedback resistors in the op amps stages without the op amps there?

Edit:  It works fine with all the chips in, just has the high pitched noise (just not sure of the source yet)

[benny_profane]

Could be an issue with your power section. I'd start there if only to rule it out.

[mcasemo]

Yep, power supply issue.   I jumpered R58 initially, then just thought it had to be clock noise and got off track with thing passing signal without chips.   I had some 1/2 watt 46 ohm resistors i stuck in in parallel, and it's all good now.   thanks for getting me back on track.

[benny_profane]

Nice, I'm glad that sorted it. Yeah, any time I hear a 'whine,' I check the power section first. Also, be sure to keep your I/O wires clear of clocks to avoid interference.