Author Topic: Questions on Local Battery Vs Common Battery  (Read 2856 times)

Offline trainman

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Questions on Local Battery Vs Common Battery
« on: April 14, 2011, 02:51:35 AM »
First, what are the differenced between common battery and local battery?

Are all non-dial, magneto sets local battery?




Tony

Offline dsk

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Re: Questions on Local Battery Vs Common Battery
« Reply #1 on: April 14, 2011, 03:50:36 AM »
Almoast. L.M.Ericsson has made some C.B. sets with a signalling generator to the other party, not familar with those.

Generally magneto indicates local battery.

dsk

Offline bingster

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Re: Questions on Local Battery Vs Common Battery
« Reply #2 on: April 14, 2011, 05:45:44 AM »
And the gist of the difference between common battery and local battery systems is that with common battery, the current used to operate the phone is sent over the wires by the telephone company central office, whereas the current used to operate a local battery phone comes from dry cell batteries attached to the phone in the customer's house.
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Offline Owain

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Re: Questions on Local Battery Vs Common Battery
« Reply #3 on: April 14, 2011, 05:49:45 AM »
First, what are the differenced between common battery and local battery?

Are all non-dial, magneto sets local battery?

Local battery has a battery in every telephone to provide talk current for the transmitter; central battery has one battery at the exchange.

I think some military magneto exchanges were central battery; each line had a neon across it, and the extension would ring the magneto causing the neon to flash. The operator would plug into the line and the connexion would proceed on central battery principles. Local battery would be a major reliability issue for military.

The UK also had Central Battery Signalling (CBS). The CBS systems provide automatic signalling similar to that of the Central Battery system. The difference being that the telephone had a local battery to power the microphone and that the central battery in the exchange supplied power for signalling purposes.