Abstract: A Split Phase Bi-polar Date Receiver is contemplated which uses an Interval Detector to measure the time interval between excursions of the bi-polar signal away from zero. This time interval or bit period is compared to predetermined intervals associated with different types of received bits, i.e., data, synch, etc. A Synchronizing Pulse Counter is provided to enable the receiver only if a specific number of synch pulses have been received indicating that a valid message is following. The enabling signal conditions a Data Clocking Path and allows the data bits to be accepted by, stored-in, and read-out of the Receiver Data Register. If the incoming data bits are of the proper duration, the Time Interval Detector produces an output data pulse which together with the enabling signal from the Synchronization Counter allows the data bits to be entered into the Register.