pulsing key

pulsing key

[′pəls·iŋ ‚kē]
(communications)
Method of passing voice frequency pulses over the line under control of a key at the original office; used with E and M supervision on intertoll dialing.
System of signaling where numbered keys are depressed instead of using a dial.
References in periodicals archive ?
The original is house at it's best with pulsing keys over a pounding bassline before going off.