Great Cheddar..might need debugging

Started by The Tourist, September 19, 2007, 09:16:08 PM

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The Tourist

I've recently finished up a Great Cheddar and am getting fuzz out of it..it sounds sort of similar to Big Cheese clips on the net and all controls work. However I'm not really getting the high levels of gain and sustain as reviewed. There's actually more gain and sustain out of my Rat. It sounds pretty decent playing on the lower strings, but if I try to go up on the neck on the high E or B, I get that gated sound similar to the wedge setting on all other settings. The other settings are different, but high on the neck they still have that sharp quality like on the wedge setting and notes die fairly quickly...enough to where I'm sure it wouldn't be considered high sustain. I checked the op amp voltages and they're different than from what was mentioned in the project file..so I measured the other opamp and the trannies..they're listed below. Any idea where I should look for problems? I didn't do any mods..trannies are 2N3904's, and I used TL071 op amps. Here are my voltages -

Battery without clip, voltage at pcb input - 9.0

U1
1- 0.1
2- 4.0
3- 0.2
4- 0.0
5- 0.0
6- 4.0
7- 8.2
8- 0.0

U2
1- 0.1
2- 4.0
3- 0.2
4- 0.0
5- 0.1
6- 4.0
7- 8.2
8- 0.0

Q1
E- 0.0
B- 0.1
C- 1.0

Q2
E- 0.4
B- 1.0
C- 0.8

Q3
E- 0.0
B- 0.0
C- 0.0
Here's the project file - http://www.generalguitargadgets.com/diagrams/geo_great_cheddar_v6.pdf

Keep in mind I'm using an analog meter with a needle so it's probably not 100% accurate. If this is a big issue I can try to get a better one.

The Tourist

Bump..What I'm most afraid of is if this is actually how it's supposed to sound. But I doubt that's the case since I got those weird voltages ???

The Tourist

Last night, just for a few seconds, I noticed some light smoke coming from the corner of the pcb where U2 is. I believe I was just looking over my joints and had a patch cord in the input jack. Could there be something wrong with U2? Is there a way for me to check? Any ideas as to what might have caused the smoke? I remeasured U2's voltages and they're the same as before.