So...
I was looking at buying an older Williams engine that had their Tru-Sounds system in it. From what was discussed here, it senses and uses the track voltage to determine function, such as choosing between bell (low speed) and horn (high speed), as well as changing the diesel sounds and the chatter/dispatcher sounds.
If I buy the engine and throw in a ERR module for the AC Commander, that'll get the engine moving, but what about the sounds? I thought about running the two leads in parallel with the input of the motor, but then it struck me. Do these boards work by controlling the voltage to the motor or is it more like pulses of track voltage timed out to make the motor spin at a slower speed? If it sends 18VAC down in pulses then the voltage sensing stuff certainly will not work at all. In fact, if I go down this route, I am unsure if the classic TMCC still sends any "classic" horn/bell voltage down the track. If not, maybe there's a way I can rig up a decoder from the sound connector and use that to inject in that extra DC pulse.
Again, maybe I am barking up a power pole and not even a tree. Any insight on this idea?