/BitBot

Robot/Pitch Shift Effect Module

Bit Bot

Robot/Pitch Shift Effect

This is a small, simplified clone of the Death by Audio Robot guitar pedal, stripped down to be installed in toys/keyboards as a mod.

Notes:

  • Can Connect Pin 3 of Control Pot to Ground via a Capacitor (~47nF) to mod the control
  • Has an optional PWM LED connection that changes LED brightness to correspond to input volume.
  • Add a Wet/Dry Control by Attaching a 100K Lin pot to:
    • Clean/Effect Input (pin 1)
    • Output Jack/Speaker (pin 2)
    • Effect Output (pin 3)

Parts List:

(Asterisked parts only needed if you use the indicator LED)

  • HT8950 (the DIP 18 version, not the 8950A DIP 16 one)
  • 500k Linear Potentiometer
  • Switches x 3 (if using switches to set mode)
  • Momentary Buttons (normally open) x 4 (if using buttons to set mode)
  • *LED (pretty much any kind you like will work I expect)
  • 100nF film (or ceramic) capacitor x 3
  • 100uF electrolytic capacitor (any voltage rating I know of will work, but say 6 volts just to be specific)
  • 10uf electrolytic capacitor
  • Resistors:
    • *220R (the IC's datasheet doesn't include this resistor, I just can't bring myself to put in an LED without a resistor. You'd probably be fine just to jumper this, or pop in any value between 100R and 1k, I just have a ton of 220Rs and can confirm this value works great)
    • 4.7k x 3
    • 470R x 2
    • 100k

Demo:

https://youtu.be/_ONI_Kui6XI

Not required or expected at all, but if you like it you can use the Sponsor button to buy me a beer!