Name of entrant: Perrow / Pelle
Pedal name: Bemired Ikon Ten
Tell us a bit about the pedal: It's a Tonebender Mk II. This
was to be is my first use of a bunch of germanium npn transistors (AC176) I bought a while ago,
but sadly, even though I've tried all I can think of I couldn't get them to bias correctly. I finally got what was wrong with the biasing and I'm quite pleased with the result.
I post a layout with the standard values (as found on
fuzzcentral, the Tonbender Professional Mk II schematic (although the 5 and 50 uF caps are changed to 4.7 and 47 respectively). In my pedal I had to drop the collector resistor on Q2 to 22k to get Q2 to bias, but I guess that's germanium for you.
As I like to do when I can, all wires going to the switch are positioned in the center of the layout as close to the switch as possible and the power is connected close to the dc jack. The pots are board mounted (but, on this design, requires a little distance to the board so they don't touch the ground path going under the volume pot). The led is board mounted on the track side of the board. This arrangement means that the led must be adjusted to about the right height and the hole for the led needs to be quite close to where it needs to be (it can be adjusted a few millimeters), but all this minimizes off board wiring and really makes it a breeze to do it nice.
What's with the name?: Well it's an anagram (the same characters mixed up) as "Tonebender Mk II", used an online anagram generator to come up with the name. Don't worry if you don't/didn't know what bemired means, I had to look it up too. It means something has got mud on it. So the meanings are.
Bemired: It's a dirt pedal with bemired graphics and knobs.
Ikon: The Tonebender is an iconic pedal.
Ten: Ten year anniversary.
Sound sample, first clean, then about 1/3 gain, then gain all the way up. Boring playing included free of charge.
https://dl.dropboxusercontent.com/u/20165528/Bemired%20Ikon%20Ten.mp3Exterior:
Interior (this shows when I had 2N3904s in there, picture of current germaniums below):
Germaniums installed and you can see the gap between the pots and the board:
Close up of knobs:
Layout:
Schematic:
http://fuzzcentral.ssguitar.com/mkII/mkIIschematic.gif
