Well, there's too many inductors and such with most traces on the top of the PCB hidden under components to bother tracing out the rest of the circuit but I DID put a 2230NZT and one of the little 6 pin transformers in a breadboard following the circuit diagram I posted in my first message and found that any quickly rising or falling signal going into either of the two other windings of the PCA EPA267B creates sharp spikes on the winding connected to pins 6 and 7 of the 2230NZT and causes what I'm assuming is the output (pin 1) to flip from high to low which makes sense because it the goes to an input of an74LS423 monostable.
SO...
Running at 5V, the output of pin 1 flips from 0V to roughly 4.2V. If I remove the transformer from the circuit and directly connect a 2.4V or higher square wave into pin 6 (leaving 7 floating) the output is NOT inverted and the same signal into pin 7 creates an inverted output on pin 1. It's like a comparator that's set to flip at 2.4V (maybe it's set for half VCC?) on fast rising edges.
This only works with square waves, triangle or sine do nothing and switching from ramp to saw makes it either latch to high or low I'm assuming because saws and ramps only have one quickly rising or falling edge.
Some kinda comparator? I don't know enough about this kind of stuff.