[stuiec]

I was reading up on old phone tech where the ph co. runs there service generally around 50 Volts DC. Then, they will superimpose 90 volts AC @ 20 Hertz to make the phone ring.

What is stopping the two voltages from conflicting with each other?
Aren't the two voltages additive in some way, shape or form?

This is got me all worked up.

Draw it out.