Multivox Fullrotor leslie sim: An easy accessory for variable speed control

[Processaurus]

A trade with a friend for fixing busted stuff landed me this relic, from what little information I've been able to gather, its a Japanese Leslie sim from the seventies (but its really just a phaser of sorts), its an all discrete circuit like the univibe, with what looks like quite a few phase shift stages, judging by the forest of capacitors.  I'm curious about how it works (and of course how to mod the collectability out of it ) if anyone can shed any light on it.  It has a depth knob, and then this red lever switch that goes from fast to stopped to slow.  Thats it!  The cool thing is that there is a ramp in the rate when you change the switch.  Things got interesting when I noticed theres this "pedal" input on the back, and when you plug a footswitch into it, you can stop the LFO.  The cool thing that I figured out though, is if you put a variable resistance (0 - ~250K) to ground, you can get the entire range of speed, from fast to ultra slow.  The ramp is still there though, as you move the pot around though.  Heres the (collector friendly) remote I threw together:



Theres a 250K pot in there, as a variable resistor to ground, and a 10K trim pot in series with it to get the minimum speed from the LFO before it stops oscillating.  The footswitch (SPDT) was originally to stop the LFO, but it got changed to disconnect the pot, because it could get a little faster with no load on it.  The knob is from the dumpster at work.  Its easy to turn with a foot, because it sits up a bit higher than the footswitch...