Weather satellite image signal clipping device - clips image signals where levels fall below lower threshold or exceed upper threshold

摘要

The device has a receiver input circuit (1), a high pass filter (2, 3) and a clipping circuit (4, 5) for clipping the image signal when its level is below a first predetermined threshold. A second clipping circuit (7, 8) clips the signal when its level exceeds a second predetermined value. The second circuit preferably includes a pnp transistor (7) and a potentiometer (8). The base of the transistor is connected to the potentiometer, the emitter is connected to the image signal, and the collector is connected to earth. ADVANTAGE - Reduces problem of long time constants in receiver circuit due to slow transmission and reduces problems of drift and overlap. Fast regulation.