":The norm for British & American dials is that the correct number of pulses is generated as the dial returns to rest, its speed being controlled by the built-in governor in order to sent the pulses at the correct rate (normally 10 pulses per second).  There is a natural delay introduced between the last pulse (or only pulse in the case of the digit ""1"") being sent and dial reaching its natural position, then an aditional delay before any further can be sent by the user turning the dial clockwise for the next digit.   So the inter-digit pause is comprise of BOTH the last part of the return movement of the dial and the time taken to ""wind it up"" ready for the next digit.  In fact in many types of P.O. dial mechanism there was also a slight additional pause immediately upon releasing the dial and before the first pulse was sent, due to the design of the mechanism.  In the SxS switches which predominated in the British network, the inter-digit pause had to be long enough to (a) cause the relays in the current stage to recognize that the dialing of the particular digit had finished, and (b) to allow sufficient time for that stage to find a vacant circuit to the next and for that stage to prepare itself ready to receive the next digit.  31.185.230.165  

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