Reference circuit produces noise-free potential - from TV signals by suitable clamping and reduces effects of horizontal flyback noise

摘要

The reference circuit produces a reference potential from television signals that is independent of the noise arising during horizontal flyback. During the horizontal sweep and within the vertical blanking interval, the television signal is clamped at a first constant potential. The part of the television signal occurring during the horizontal flyback is held at a second potential equal to the first. A blanking circuit is connected to the output of the clamping circuit that holds the television signal to the first constant potential. The blanking circuit consists of a series resistor and an electronic 'earthing' switch that shorts the TV signal during horizontal flyback.