John,
You mentioned the AC remote-control relay that was operated by shorting a low-voltage winding.
Over the years I've needed exactly such a relay, and I remembered them from dozens of 1960's vintage hobbyist electronic magazines, but for the life of me, I couldn't remember what they were called or who made them.
I can't remember a specific name or manufacturer either. I do remember picking up one of Tab Books ubiquitous projects books from the early 1970s when I was a kid which was projects almost entirely based around these relays: A remote low-voltage switch for a lamp, TV commercial silencer, a control for a pedestal drill with the secondary coil between the drill ground an insulated plate on the base so that the drill would start automatically when the bit touched the metal piece being drilled, etc.
Unfortunately, that book went on a clear out a good few years ago, so I can't check on the manufacturer.
