Here’s what it looks like with some graphics.
I’ve fixed one issue with the speed preset switch, it could sometimes skip one of the three speeds, jumping from slow to fast skipping medium. It now goes steady from slow (1Hz) -> medium (2Hz) -> fast (7Hz).
I’ve made the depth trimmer available from the bottom lid and added a trimmer for the fast speed as my client requested, adjustable 3- 7Hz.
So lets try to list what differs from the original.
- I’ve used 2N5952 fets instead of the 2N4303.
- It’s got a new input buffer suited for guitar.
- It powerded by 9VDC.
- Adjustable high speed.
- The speed selector circuit, tap the switch and change the speed.