Debugging Phase 100

[Xlrator]

Finally got this to make noise!! It phases, but it has a horrible squealing when effect is switched on. I poked around with an audio probe, but there is squealing almost everywhere, even on my signal coming in.

Some of the problems I corrected were: Had JFETs instead of NPN, dead trimpot, and one jack from my power supply was reversed.

Anyone have an idea or know what it is?  :?

This is the GGG layout.

*edit* My .01uF caps are ceramics. Should these be changed to films?

[Impaler]

Ceramics shouldn't matter much, altho if they are specified, you may want to use them.

As far as your squealing prob, all I can say is set it aside for an hour or so and let you eyes rest, then come back to it. Check your wiring and connections again... Rinse and repeat as necessary until you get it to work =P

[Xlrator]

Well, I haven't put it down yet. I changed the caps to film and I changed opamps. I did find a discrepency, the bill of mat. says TL072 (JFET), and the schem. says TL022, 4558, etc. (not JFET). I don't have 6 TL022s, so I put 4 in and 2 4558s. No more squealing, it's phasing, but it cuts in and out. If I skew the board it works fine. Now I have to find a soldering prob!!

This is fun!  :lol: