To talk about how I would give this user ringing to station and buzz back... can happen with a 551 with ring generator and rt1900. I have wired a few to do this. You can never learn enough about 1A2 and it's possibilities. One can never learn enough about the given concept electrical ideas an old one's in itself being part of a rt 1900 era. Why not dial and turn on the lights
or open the garage door? After all there 19 relay paths.

RT36 even better.

The new RT 96000 microwave tone commander relay. On sale now! With remote notification to eject.

Some days I think they used just a RT 36 to land on the moon.