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.

Wednesday, October 14, 2015

Run Off Groove 3 Legged Dog

Got a bunch of CD4049UBE chips left over from building Red Llamas? Here's something else you can do with them. You might need to play with the the value of the 8.2k resistor going to the drain of the J201 to make sure you're getting to around 4.5v there. Also if you encounter squealing or unwanted noise, try increasing the power filter cap from 47µ up to 100-220µ. Sound clip and schematic can be found here.


  1. Love the artwork on the PCB. Great job.

  2. It's like a Red Llama boosted with a Jfet... am I right?
    Would be awesome with the BM Tone Stack

  3. did anyone expand this circuit with a tonestack (maby active)?

  4. Verified.
    Sounds pretty good. I'll have to build the ROG Double D to compare.
    I did try adjusting the JFET drain resistor and 24k got me about half supply voltage on the drain. 8.2k to 24k seems like a big leap, but the ROG Double D has a nearly identical JFET stage with a 50k trimmer for the drain resistor. When turning up the gain, I got more whine with the larger drain resistor. I went with the stock 8.2k. It still whines with the gain up, but other build reports suggest that boxing the circuit may take care of the noise.