Transistion-rate discriminators

Telegraph signalling waveforms consist of a series of mark-space or space-mark transitions that represent points at which the rate of change of information is a maximum. This rate for an error-free message depends on the signalling speed and increases for perturbations due to noise. The differences in rates can be detected in a transition-rate discriminator and the information used to provide a utilization voltage. Such a discriminator for 50-baud operation is illustrated by a detailed circuit schematic and discussed in conjunction with typical graphs of results obtained. The application of the discriminator in dual-diversity radio receiving systems is particularly mentioned, and a block schematic for a dual-diversity switched aerial system shown. Reference is made to pending British Patent applications.