Introduction and My AE..

[Stan the Man]

Stan S,.. I get 48+/- ohms on the coil.. If I drop a nickel in the top, it falls through and sets the micro switch.. 9 volts to the coil will reset the switch.. What is confusing to me is, if I drop a second nickel, it also resets the switch.. Is this correct?? If the second nickel resets the switch, what purpose does the electromagnet serve?? I'm posting pictures of the switch in the set and unset position..

[rdelius]

So if one nickle is deposited, it can be refunded

[Stan S]

Stan
Don't worry, the assembly is working properly.
In order to understand the purpose of the reset electromagnet you have to look at the way the entire payphone operates.

There are two sets of switch contacts in the payphone in parallel with the pulsing contacts of the dial. The first set of switch contacts is the microswitch on the nickel counter. The second set of switch contacts is located on the coin relay. When either of these sets of contacts are shorted the dial is useless.

Both the coil of the coin relay and the coil of the reset electromagnet of the nickel counter have voltage applied to them at the same time by the collect or refund voltage sent down the phone line and ground by the Telephone Central Office.

When the payphone is sitting idle with the handset hung-up, the microswitch contacts of the nickel counter are in the OPEN position. However, the switch contacts on the coin relay are closed. Which makes it impossible for the dial to work.

Mr. George Gray comes along and wants to make a call. He lifts the handset of the payphone and gets a dial tone. (All prepay AEs gave a dial tone when the handset was lifted.)

If George tries to use the dial it won't break dial tone because the pulsing contacts are shorted by the coin relay.

George deposits the first nickel. The nickel travels down the coin track hitting the spring wire of the nickel counter. The position of the microswitch on the nickel counter changes- the contacts are now shorted.

The nickel continues down the coin track and falls into the hopper, hitting the coin vane. The coin vane is the activator for the switch contacts on the coin relay. The set of contacts on the coin relay that were shorted originally now are an open circuit. However, since the contacts on the microswitch are shorted the dial pulsing contacts are still disabled. Turn the dial and it still will not break dial tone.

George now deposits the second nickel. It travels down the coin track and hits the spring wire on the microswitch. The position of the spring wire changes again and OPENS the microswitch contacts  The second nickel continues down the coin track and falls into the hopper. Since the coin vane of the coin relay has already been triggered (in the down position) the second nickel has no affect on it. We now have two nickels sitting in the hopper with both sets of switch contacts (microswitch and coin relay) in the open position. George now turns the dial which breaks dial tone. George can now make is call. He's probably calling some company in Hartford Connecticut.

When George's call is finished he hangs up. The central office sends a collect or return voltage between the phone line and ground that triggers BOTH THE COIN RELAY AND THE RESET ELECTROMAGNET OF THE NICKEL COUNTER putting them in their reset positions. Both the nickel counter and the coin relay are now ready to handle the next call.

Let's assume poor George Gray puts in the first nickel and for whatever reason decides he doesn't want to complete the call. When he hangs up the Central Office will send a return voltage down the phone line. George will get back his nickel and both the coin relay and the nickel counter will be reset.

Remember, the payphone sitting idle has BOTH sets of switch contacts in the OPEN position. If nothing travels down the nickel slide of the coin track George Gray can make his call by depositing a quarter or a dime.

Anyone know what happened to poor old George?

[Stan S]

Remember, the payphone sitting idle has BOTH sets of switch contacts in the OPEN position. If nothing travels down the nickel slide of the coin track George Gray can make his call by depositing a quarter or a dime.

Correction!
Remember, the payphone sitting idle AFTER a deposit of a dime or a quarter is made, will allow George to make his call because both sets of switch contacts are OPEN, since nothing has traveled down the nickel slide.

[AE_Collector]

Anyone know what happened to poor old George?

Died of a stroke when he heard that the Telco's wanted to increase the charge for a local call to 25c and the payphone would need nickle and dime switches to figure out all the possible combinations adding up to a correct initial deposit?

Excellent description of the operation of the nickle switch in a 3-slot payphone Stan S.

Terry

[Stan S]

"Died of a stroke when he heard that the Telco's wanted to increase the charge for a local call to 25c and the payphone would need nickle and dime switches to figure out all the possible combinations adding up to a correct initial deposit?"

Laughing, laughing.
Good one!
Still laughing.
Stan

[Stan S]

Terry
We should all live the way George lived. His estate in Ct. is so large that the various buildings are being divided and sold as condominiums. I believe he was on the BOD of 6 companies (Colt Firearms I think was one of the.) At the time he received $100,000 from each corporation. We are talking about a time when the guys that worked in his foundry probably made $30 a week.

The following is all from memory.

Gray sold out to Automatic Electric in 1948.
When the Gray Mfg patents for the gravity drop coin signals ran out in 1937(?) Western Electric begged Gray to make the cost of the part of the payphones they manufactured (by previous court order) more realistic. Western really didn't want to manufacture the entire payphone.
Gray had been forcing Western to send the same parts back and forth multiple times costing big bucks in shipping and delays, for no reason.
Western Electric threatened to start manufacturing the entire payphone themselves. Apparently George didn't like being threatened. Hard to survive when you loose over 80% of your gross business. Not a good idea to kick the bear!
Don't know when he died. A long time ago I Googled his estate -UNBELIEVABLE!!!

[Stan the Man]

Stan S,.. If that didn't explain it, I don't know what would.. Much thanks.. When the hopper gets here I'll post more pics and a question or two..


Thanks again,.. Stan T

[Stan the Man]

Well,.. its finished,.. for now.. With a few parts and much help that is GREATLY appreciated..
It is now an LPB-82-55..
Stan

[Stan S]

https://www.youtube.com/watch?v=A0M75m7vHf0

Stan S.

[HarrySmith]

Stan, thanks for that explanation of payphones. I have a glimmer now of how they work after reading it a few times. I will continue reading it to learn more. I am going to open my payphone and compare as I read. I should finally be able to figure it out!