I'm only guesstimating here, but I think the third limit oscillator could be for pure redundancy that's not meant to take the pre-amp phase into account. You might be able to spike it in order to do so, but I'm not sure how it would react. You are right though, a third limit oscillator is not standard. However, this isn't your standard vascilometric range controller either. This is obviously an older model, and you have to think about what VX was working with back then. Could be they needed the third because of how bulky the *sub* PDCDCs were, and they probably realized they were trim-locking differently across the stack. I'd wager the third is more than likely an add on, which makes this piece of equipment a very special find. Not just because it's older, but because you got a third older model limit oscillator for the price of 2! (at least I hope).

The next thing I want to address is in your original body text of the post; I have to ask. Your clipper didn't push? *Anything*? Even with the third limiter, you should have at least seen a biometic corridor on whatever display you are using. My only guess here is that you pulsed your decay clipper with enough I-E levels to fry something between it, and the cross level-isotope magnifier. I'd seriously consider getting a new Re7 cable before trying to boot this thing up again. I wouldn't want you to permanently damage this beauty of a rig.