A dial consists of a fixed part that is mounted on the telephone set and a rotatable part with usually ten holes into which the finger can be inserted. By inserting the finger in the appropriate hole and rotating the dial with the finger as far as the stop at the bottom right, a spring is tensioned. As soon as the finger is withdrawn from the hole, the dial rotates back at a fixed speed, with two little balls briefly interrupting two contacts. The number of times this happens corresponds to the dialed digit, except for the zero. When the zero is dialed, the contacts are interrupted ten times.
In the telephone exchange the pulses are decoded. In the past, this was done with a stepping relay.
This obsolete method is nowadays called pulse dialing, in contrast to the more modern tone dialing,
Hello I am 56 years old and live in Delft.
Photography is for me a representation of a feeling.In 2002 I photographed with a nikon FM.Now there is more "time" the "eye" is back in the active mode. Have a lot of fun!..
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