The ratio is the main difference between a compressor and a limiter. A compressor has a low ratio that turns down SOME of the volume when it goes above the threshold. A limiter has a huge ratio that turns down ALL of the volume that goes above the threshold. (from Musician on a Mission)
Here's the schematic for reference. It's designed as a buffered bypass pedal, with the input jack going to the In pad on the board, and a third of a a 3PDT footswitch selecting between the buffered out and effect out. The off board LED pulses with the signal but probably isn't going to be great as an on/off indicator. Just use another third of the 3PDT to make/break the connection between the LED- pad and the cathode of the LED. And then use the final third of the footswitch to wire an on/off indicator LED as you normally would. (At least I think that's what Bajaman had in mind...) Also, the LDR should have 5k light resistance, 500k dark resistance (a GL5516 should work). Oh, and I added an extra pad so GSD pinout JFETs (J201, 2N5457, etc.) can be used in place of the 2SK117.
