Another Super Fuzz build. I used the first PCB I designed from a post over at FreeStompBoxes.org, read about that first build here.
This one looked good but it didn’t work! I put it aside because the problem wasn’t obvious. I got it out again and set at debugging. After a few minutes with the multi-meter, I took a close look at the transistors, they were 2N5401 types, not one I’m familiar with, a quick look at the data sheet realizes that these are PNP types! No wonder it wasn’t working, this circuit needs NPN types.
Not sure what I was thinking, I must have a bunch of these in a bag that is mislabeled? Not sure.
A few minutes desoldering, and 6 2N5088 transistors installed, and this was working great! Sounded better than I remember! Not sure if the hotter transistors made any difference.
The original used TPQ2222 and 2N2913 devices. The internet thinks TPQ2222 have a typical hfe of 30 and 2N2913 is typically hfe of 60. The 2n5088 transistors should measure between 300 to 900. The bag I have measure typically around 400. So these are much hotter.
Some circuits really like low gain transistors, I don’t think that this is one of those!
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