What is the number you can dial, to make your own phone ring? How is it done?

There is a three digit number you can dial which tells the phone company to redial the number you're calling from in about 10 seconds, used as a diagnostic tool for phone technicians. I know what you're talking about, although I don't remember the number. Since it's a phone company thing, I'm pretty sure it varies from provider to provider, IE. Verizon and AT&T have different numbers to do so.

You can call your home phone number. It will come up as busy, then hang up. The phone should ring. Or dial your home phone from a cell phone. What is this for?

call the operator dial 0 and have them ring your phone back

Dialing 555 rings back my phone. I have AT&T.

you dial ur own phone number.

your own phone #

intercome from a handset to another