atcomsystems.ca/forum Forums General General Telephone & Systems Information WEAK BELL IN OLD PHONE

Capacitors are either for blocking DC voltages or storing DC voltage.

When put in series with a ringer coil it allows the AC ring voltage through but blocks the DC battery voltage. You do not want the battery voltage on the ringer coil because it can draw enough current to make the line go off hook. This of course depends on the DC resistance of the ringer coil and they are all different. So what you say Bobby would happen with some phones but not all.

-Hal

thanks to all for your help! my next prodject, not that is one is finished:), is a payphone. would love to get and old type payphone that have, i think nickel, dime and quarter slots, and "dings" when you put the coins in. didnt the operator know what amount of money you inserted by the ring each coin triggered?

bob

I think the way they knew which coins were deposited was by the length of time a ground was on one side (TIP I think) of the line. The coins triggered some kind of mechanism in the phone that applied the ground as they dropped into the phone.

Actually, both. Eventually it became electronic and displayed the amount for the operator! Some operators had to deal with all three types! You'll find payphones on e-bay. And someone give him the collector websights. John C.

Each "ding" is 5 cents, each "dong" is 25 cents. A dime goes down a chute that hits the bell twice. A carbon transmitter was part of the coin chute to deliver the sounds to the operator.

When all the operator had to go on was the sounds, you would find two payphones next to each other, hold the handset next to the 2nd one and put the coins in there. Since it was not actually in use, the coins came back through the coin return.

Single slot payphones sent MF tones to the billing computer, this time one beep per 5 cent increment. Phone Phreaks came up with the "Red Box" to simulate these tones through the handset.

We had to go around and put short cords or armoured cords on so they would not reach the next payphone when there were a bank of phones in a row.

nice info guys!
amazing how simple phones worked years ago when they were more of a luxury than a necessity. now there are a gazillion wires,optics, etc, attaching phones to computers!...bob