The main function knob on the FY6800 signal generator I own is painfully thin. Making fine adjustments using one hand, when the rest of yourself is concentrating on holding a probe at the right angle and observing oscilloscope or DMM readouts, is hugely inconvenient. The smoothness of the knob adds to adjustment difficulty with sweaty fingers (anxiety is common when probing circuits).

To that end, I designed a thicker and chunkier knob that fits on the shaft of the existing rotary encoder, and makes adjustments less painful.