skreddy screwdriver???

[CoolJohnny]

love the way this box sounds. I have some old AC 127s to use up and I thought I would give this one a try. j
ust to simplify things I thought about leaving off the BS 170 buffer at the front. anyone tried this before? I am planning on leaving out the brilliance and tone pots as well...

[nocentelli]

http://1.bp.blogspot.com/_y4AYtND8Hz8/SfW7W20GXtI/AAAAAAAAAWI/Lz6vXJQUmwY/s1600-h/screwdriver_1_2.png

The mosfet Q1 is not just a buffer, it's boosting the signal considerably once you turn the pregain up a bit. The rest of the circuit is like a hybrid Si/Ge fuzzface, but it will sound different without the mosfet pushing it. As for the "sharp"/ body pot, I like it in the lunar module (which is very much like the screwdriver, but with a silicon bjt Q1 pushing a silicon "fuzzface" Q2 +3 - all BC109c) but I have built several versions with that pot and surrounding caps + resistors all replaced with a single cap, usually 100n, and it sounds good. A fixed tone/brilliance pot with your preferred tone setting replaced with a single resistor in series with that 3n3 cap also works fine on the lunar module. If you want fewer pots, you can replace the two gain pots with a single dual gang 2k pot (with a 2k resistor across lug 1 and 3 for the Q3 half) - also works well with the lunar module.

[CoolJohnny]

so you're saying the BS 170 is .key to the units sound... mm. maybe I will do it without and then add it ttoo see the difference. thanks for the schematic, that isis the clearest one I've seen yet.