I have three mid '90s Vetta C-15 cyclo computers (color coded for different bikes). I had to rebuild all three due to oxidation in the bell switches (not ding ding, shape) and they work excellently once I found the owner's manual for one. When I was building the touring bike I found a NIB VDO wireless in the parts bin, no idea WRT vintage nor why I originally bought it. Old enough to be effected by outside radio signals as I can go from 17 MPH to 3 MPH or to 36 MPH in a nano second.
Brad