Black-white TV signal regenerating system - eliminates grey using black-white discriminator and adds amplified sync. pulses to signal

摘要

The black/white television signal regenerating system has the noisy television signal applied to an input amplifier (1). For this purpose the TV signal may be produced by a camera viewing a projected microfilm. The input amplifier divides the TV signal into two parts having the same information content. The first part is applied to a discriminator (2), and the second one to a separating stage (3). The discriminator evaluates its input signal in terms of grey level and produces a black signal when a given threshold is exceeded, or a white signal when it is not exceeded, thus eliminating the grey. The separating stage amplifies the sync. pulses and suppresses the rest of the signal. The outputs of the separating stage and the discriminator are then combined (4) to give the proper TV signal.