build your own Ugly Face!
Ugly Face is a racus squarewave guitar synth oscillator disguised as a fuzz pedal.
Originally created by Tim Escobedo on his Circuit Snippets web page, it’s become a DIY classic. The ideas here are great and inventive there are a lot of building blocks. Out of all of these the Ugly Face leaps out at your like a rabid warthog.
The board here was design in Eagle PCB. The pots and LED are mounted to the board for easy assembly. Get boards at:
- Order Super Frequency boards from PCBWay.com
- Order from OSH Park
Notes: Solder parts to boards without the LED or pots. Drill your box with the guide at the end of this document. Fit the pots and LED in the board without soldering. Mount the pots into the enclosure with the nuts and washers. Then fit the LED through the hole. Now solder the legs of the pots and LEDs.
NOTE! I found an issue with the ground connection on the output side. It’s not connected to the group plane! Otherwise everything works.
| Part | Value |
| C1 | 22µ |
| C2 | 1n |
| C3 | 100n |
| C4 | 2µ2 |
| C5 | 100µ |
| C6 | 470n |
| C7 | 100n |
| D1 | 1N5817 |
| D2 | LED |
| Envelope | B1K |
| Frequency | A50K-A100K |
| Threshold | B10K |
| Volume | A100K |
| R1 | 1M |
| R2 | 470 |
| R3 | 100K |
| R4 | 22K |
| R5 | 1K |
| R6 | 1K |
| VACT | Any LED/LDR pair will work |
| 555 | 7555 |
| LM386 | LM386 |
