[GreenKeys] Ring generator.

[Sam Hallas]

KD7JYK DM09 wrote:
>  Has anyone ever experimented with a chip, for example, a 555 or basic
>  stamp, providing the proper Hz, then kicked up through a transformer,
>  to activate equipment looking for a "ring" signal?

Oh, Yes, Kurt. In the old days before off-the-shelf solid state ringers 
were available lots of folk made up their own with, say a multivibrator, 
filter and audio amplifier chip feeding into a 100v line speaker 
transformer. I've seen just a simple commutating circuit from the 50v 
exchange supply used to produce ringing without a transformer. And that 
was in a commercial key system!

By the way what's a 'basic stamp'?

Sam