This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Friday, August 21, 2015

Fulltone 69

Happy #fuzzfriday, everybody! The 69 is Fulltone's take on the classic, late 60s, germanium Fuzz Face circuit. They've added a few extra controls to help shape the fuzz. The Bias (or Input as it's called in the 69 Mk II) pot is a common mod to the Fuzz Face circuit (it's a trimmer in the AnalogMan Sunface) and controls the input impedance. It can clean up the sound a little, just like rolling down the volume pot on the guitar. The Contour pot controls some of the voltage going to Q2 and the output cap. For more info, here's the schematic. Pots can be board mount from the solder-side of the circuit board and it should all fit in a 1590B just fine. The perf side of the drawing shows positive ground and the PCB side shows negative ground. Typical Fuzz Face germanium transistors should be used (Q1: hFE ~70, Q2: hFE ~100), but as always, socket and experiment.




10 comments:

  1. Hello! Does palaridad correct? I think this is positive ground EFFECT

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    Replies
    1. The left side (perf) shows positive ground, the right (pcb) show negative. Just depend on if you want to use NPN or PNP germanium transistors.

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  2. This is my fifth pedal I've done, and the first one which began working w/o any issues!!! :)

    This is how it looks (all done by my hands):

    http://i65.tinypic.com/16bc77d.jpg
    http://i64.tinypic.com/ws4c9v.jpg
    http://i68.tinypic.com/2ekrpn9.jpg

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  3. Hi! To wire this pedal i use the PNP scheme like this? http://fuzzcentral.ssguitar.com/faq/switchwiringpnp.gif

    I tryied to do like showed here in General Layout Notes, but not work. Thanks a lot! Great site!

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    Replies
    1. Yes that scheme will work for PNP. My layout in the Layout Notes reflects the more common NPN way.

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    2. Thanks! Great site! Best in pedal's PCB world. =)

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  4. Hi! I built it and it works (pcb). but fuzz pot works well just in the end. until 3/4 is a dark light crunch and from that it becomes very fuzzy. may I change the pot? putting a 2k? thank you a lot!

    ReplyDelete
    Replies
    1. Yeah, that's fairly common with this circuit and other Fuzz Face variations. Try a B2k pot or a C1k (rev log).

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