Before Lionel modular boards, these boards were removed from models, before TMCC upgrades. QSI boards were used in Weaver models. QSI is still in business.
I don't have these boards. I posted this picture, many years ago, and a forum member ask for them. Usually, the piggy-backed boards, were from a model that had sound. ???Horn continuous, would indicate the motor not turning???. At the time, there was the "Three clangs of death", mode. Best of luck with your project. Mike CT.