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, June 8, 2018

EarthQuaker Devices Dirt Transmitter

To close out EarthQuaker week, here's the Dirt Transmitter. I traced this one myself and below is a video showing the process. It's similar to a Fuzz Face, but a little different. I found this description from (I'm assuming) Jamie over on TGP:

I guess it's kinda like a fuzz face but it started as two gain stages running into each other with an input gain control and a sag on the second stage (bias). Voltage feedback was added and it became similar to a fuzz face in topology but it sounds nothing like one IMO. In this case the sound is totally dependent on the transistors, replace them and it's a whole different beast.


Here's my video on tracing the circuit as well as a demo:


   

Here's the schematic:


And the layout:


You can also order a fabricated version in the store here.

Update:

Added a perf layout for this based off the Eagle board above.

30 comments:

  1. Wow, well done! You are a treasure for DIY community!

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  2. You're a stud, David! Thank you for all you do!

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  3. Epic post. I already ordered some components. 🙃😬

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  4. just an FYI. on your perf layout the 100p from the base to collector of Q1 should be a 470p according to your schematic and your top layout.

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  5. built it. verified! it sounds awesome. thanks for drawing up the layout!

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DirtTransmitter/DirtTransPCB-01.jpg

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  6. here's pic pf my finished build:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/DirtTransmitter/DirtTransmitter-600.jpg

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  7. Awesome job.. good video! Good to follow you!

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  8. Friend how do I leave the value of the components on top of them? how does this layout. I use Eagle 7.6.0

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  9. Hey there, I'm having trouble finding the 2n1711 transistors anywhere, are there any alternates? Thank you so much great help !!

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  10. Hey david can you show a diagram that shows how to wire up the dirt transmitter. Thanks

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    Replies
    1. Was there a special way that eartquaker wired up the 3pdt

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    2. Not really. Their method is about as simple as it gets. And they don't ground the effect input when it's in bypass mode (which is generally a good idea). Just use the method laid out in the General Layout Notes tab and you'll be fine.

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  11. Ok so iam about to populate my pcb that I ordered from Oshpark which are amazingly built. I just wanted to know which caps should I use? Multilayer ceramics, polyfilm, or box? I have all the values in the multilayer ceramic but I wanted to make sure before I solder. Thanks

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    Replies
    1. You can use whatever you want. The original used a mix of film and box, but I've got not hing against multilayer ceramics.

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  12. Ok so I built this with the pcb provided by osh park and it sounds awesome!!! One question? Iam wanting to place a rotary switch that selects different components to change the sound of the circuit. Where would be the best place to put this? Thanks

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    Replies
    1. There's already a lot of control over the circuit. One of the few things left would be the input cap. You could put a couple lower value and higher value caps on a rotary.

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  13. I tried putting the pedal together and my output volume and gain are both super low. Quieter than the bypassed signal, even. Doesn't get even vaguely fuzzy. I'm pretty sure the power is hooked up right, the signal is flowing the right way, the 3PDT switch is wired up right, all polar components are installed properly. I'm dumbfounded. Do you have any ideas as to what could be causing this?

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    Replies
    1. Sounds like it's misbiased. Try adjusting R3 (22k)

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  14. I've build it and it works when i'm not putting it in the enclosure. As soon as i but the pots through the drilled enclousure it dosn't work. It goes silent or weird.
    My guess is that i've done something wrong with the enclosure grounding.
    Any ideas for that? :/

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    Replies
    1. Have you isolated the back of the pots from the back of the board?

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    2. Yes i have.
      The Sound cuts out when the pots aren't really screwed in.

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  15. Hi,

    first of all, thank you for the layout!

    So, I'm having troubles to get the 50k linear pot for the tone control. (I mean, I ordered the components online in january and that one is still backordered since then..)
    Would it be better to get a different taper or a different value of pot? My options are 50k log or REV log, or 25k and 100k linear.

    Any help is much appreciated.

    Thanks!

    Nic

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    Replies
    1. You could use a B100k by itself or add a 100k resistor from lug 1 to lug 3. That will turn it into a 50k pot essentially.

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    2. Thank you very much, I'll go with a B100k then..

      Cheers!

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