Abstract: The collector current of a first transistor serves as the base drive current for a second transistor of opposite conductivity type than the first transistor. When conduction occurs through the collector-to-emitter path of the second transistor, a conducting diode connected between the emitter of the first transistor and the collector of the second transistor clamps this collector to a relatively fixed voltage level referenced to the fixed base voltage of the first transistor. This prevents saturation of the second transistor and thus reduces the "storage delay", that is the turn-off time delay of the second transistor. In addition, the charge stored at the base electrode of the second transistor is removed when its collector-to-emitter current flow is interrupted to further reduce the turn-off time of this transistor.

Abstract: Signals producing each spot in a digital two-dimensional spot matrix display, such as in a digital weather radar, are compared on a spot-by-spot basis with signals for immediately proceeding and following spots in each dimension. When the preceding and following spots have the same value, the spot being compared is caused to have that same value when displayed. The comparing circuitry may be provided signals from a radar antenna which receives, serially, signals at succeeding range points at a given azimuth and then at the same range points at succeeding azimuths. Signals at each given range at a plurality of succeeding azimuths may be averaged to produce an improved visual display. The compared signals may be further smoothed by averaging signals for succeeding azimuths and displaying the averaged signals alternating with the unaveraged signals.