Quote:
Originally Posted by BigClick
Thank you OF. I will measure as advised.
Not sure what you mean regarding the earth signalling? This unit definitely worked as a two wire "Loop-Dis" in the past.
I believe the dial was customised on Button AB payphones to allow a 9 or 0 without having to put any pennies in the slot.
I am prepared to be educated on it though
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Earth signalling is where an earth on one leg of the line ( can't remember which as I could never see the fascination with Auto) to (on manual) called the operator or on Auto seized a switch. A lot of the older BT pabx systems used this .
One of the jobs I got involved with was checking the MDF records on our old CB manual board prior to change over to auto. Simple job- put a linesman tele across a pair and wait for operator reply. If no answer we simply put an earth on one leg. Soon found out that on an old call box, one leg earthed came up as normal call whilst the other leg showed up as an emergency.