Sorry guys I need more help. I have a pastie drive that sounds great at low volumes. However, when I turn up the gain and tone and have the Mids switch in the bottom position I get this loud squeal. I tracked it down with an audio probe and it starts on the middle lead or source of the Q1 j201
I followed the Build instructions except the IC1 I used a TL072CN in place of the JRC4580 (I have one on order)
http://home.comcast.net/~gprause/BuildDocs/Pastie_V1.1_Build_Doc%20V2.pdf
Here are some things I tried:
Took off LED
Changed IC
Tried many other j201s and even a couple 2n5457s
Here are my voltages:
Q1 G 2.97
S 4.59
D 9.03
Q2 G 2.97
S 4.73
D 9.03
Here is IC
Positive 4.52 9.04
4.65 4.52
4.43 4.52
0 4.51
The 0 on the IC seems strange to me. I also wanted to know if the direction of the Mids toggle matters (1MD6T1B1M1QE) I am getting a darker sound when it is switched up and the middle has a bit more "sparkle" then the bottom is a super bright sound, and that's why when I turn up the tone and gain it gets this loud squeal (that also can be changed as I move the gain and tone)
The other thing I noticed was that using the probe it is clear on the input, but once it starts to squeal at Q1 if I press my finger on the "Tip" solder lug of the input jack it clears up.
Here are some pictures.
(http://i.imgur.com/WJNVlpU.jpg)
(http://i.imgur.com/S2qxSCB.jpg)
I circled where the Q1 transistor is. I also put tape over that spot thinking the solder might be touching the toggle switch.
(http://i.imgur.com/JnHbMu6.jpg)
Well I went over the soldering one more time including the stomp switch, all pots, and power and ground wires. Tried some lower drain j201s I had. Then cut the j201 leads so they are flush to the sockets.
At this point Im going to leave this alone till my IC comes in.
If anyone has any other ideas please let me know.
In case anyone is following this I ended up connecting the board directly to the input and output jacks and it sounded fine. I know it is the stomp switch or board now. I am going to desolder the switch and try fix it up, if not I will just put in a new switch.
Best way to do things. Always rock it before you box it, then you know where the problem lies.
Jacob