First let me say that what I have is not an original but a clone with many more settings. Mine has an on / off switch, a speed knob supplemented by a switch to extend the adjustment range and depth knob.
The idea of Repeat Percussion is to cut the sound as a slicer, even if it is also a little tremolo when the depth is not too much in the right corner. Basically it gives the impression that it is a short sound passed through an analog delay so that he does is he cuts and resets the volume like a killswitch with the impression a very short attack as a percussion hence its name. Ha! It was the challenge of the week to describe the sound of this thing with words!
The config is very simple and takes the place of the ear manual.
This is a particularly dramatic effect not suitable for mainstream music.
This is the preferred effect of Jason Pierce of Spiritualized / Spacemen 3 and a lot of people say it's the perfect companion for a good fuzz acid. I prefer clear sound.
What I think? I ADORE!
I have a few months and I can not do without. I use it for lots of applications.
I love it so I think that one of these four I will complete a Dwarfcraft memento, which is the same thing with a recorder pattern instead of a speed button: http://www.dwarfcraft.com / memento.html