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.

Saturday, November 22, 2014

JFET Boost

Here's a quicky. It's an old Dragonfly design and was my first perf build.



21 comments:

  1. Yes clean booster ,very very perfect

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  2. I built this pedal with mpf102 and it sounds ugly, is it possible that the replacement you use is not the right one?
    The transfer image lacks a hole for a resistance of 2.2k?

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  3. What is a replacement for J201?

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    Replies
    1. Try 2N5457, or F245A. I used both, and works great.

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  4. https://www.youtube.com/edit?o=U&video_id=EITs60ZwEUI

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  5. Does this scheme work or do I need to change something in the leyout ?

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  6. To whom it may concern you can use a j113 if you change the 22k from 9v to a 10k just make sure to check pinout on transistor.

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  7. So, if you use a, say, 50k trimmer in place of the 22k bias resistor, you should be able to use other jfets and bias accordingly, right?

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  8. hii
    where i place the potentio, toogle swicth, and what value for the potentio?
    i really interest for build this pedal effect couse i have tr j201, but i dont know where potentio an push button add on this circuit, cant you teach me for wiring?

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    Replies
    1. The pot is wired off board. The pads labeled "Boost 1" and "Boost 3" tell you which lugs to connect. Boost 2 is the circuit output, and the pot is a 100k audio/log taper. See the General Layout Notes tab for offboard wiring info.

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    2. For caps, use caps polar or non polar?

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    3. Still not work, i try with J201 and the same value of resistor an caps , but didnt work.

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  9. This comment has been removed by the author.

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  10. Does anyone know if this would work off 12v.building it into preamp section of a micro amp project. If not I can add another stepdown

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    Replies
    1. You might need to adjust the 22k resistor going from voltage to drain, but I would think it'd work fine on 12v

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  11. few questions:

    can i use this with a dynamic mic without distortion? or there's some kind of problem in impedance or smthing?

    can i replace this with a 2sk170bl? any ultra low noise replacement with the same pinouts as j201?

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