Bender MK2

[Big O]

This is the 2nd pedal I ever built around 2008 I believe, a MK2 Tonebender circuit.  Not a PUTB unfortunately, because the one I built did not have a charge pump so it doesn’t play as well with other pedals.  I just updated the pedal because it didn’t have a great MK2 sound probably related to the transistors I received with the kit and improper biasing.  The original build just sounded too polite.  Finally got around to pulling the guts out, pulling a transistor off the board and replacing it with the one supplied by Small Bear to go with the Q2 transistor of the set I purchased from them.  Reassembled the pedal, biased the collector of Q3 to -4.5V as recommended on Fuzz Central and there it is!  Zeppelin I with my T-style guitar and “Greasy Supro” setting on my Reverend Goblin amp.  Now I know the bias of Q3 can be different with values up to -8V or so and may be tuned by ear (also it can drift by differences in temperatures).  Maybe one of these days I will build a PUTB and compare.  Notice the clear poly on the enclosure has yellowed giving it that old, used patina (I use clear acrylic laquer now to avoid this problem).

Gutshot.  Note the external off board bias control – the first mod I made to this pedal.  Very helpful for tuning the pedal by ear.  Now on to the 3 GuitarPCB projects I have waiting in the wings.

[Billy]

Really nice for a 2nd build

I started with a 1 knob fuzz then jumped straight in with the SWAH which more by luck than judgement fired up right away

You’d be able to fit a small charge pump daughterboard down near your 3PDT if you ever want it to play nice with your other neg ground pedals should still fit in even with a battery snap

I’ve used this one many times

http://tagboardeffects.blogspot.com/2012/05/negative-voltage-inverter.html?m=1

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