[HomeBrew] Selsyn info wanted

[Vaclav Sal]

Couple of cute selsyn motors followed me home from a swap meet. Now comes
the time to make use of them for a project not yet defined.
I have some minimal knowledge about selsyns which needs refreshing. I know
what they do and how they are suppose to operate.  
So far the preliminary search in the vast and sometime wasteland of Internet
yielded no useful info . Any guru on this reflector  which could set me in
the right direction on how to hook up the four terminals and make it play?
73 Vaclav AA7EJ