CIRCUIT FOR COUNTERMEASURING AGAINST HIT OF POWER SUPPLY

摘要

PURPOSE:To reduce a restoration time after release of hit and to prevent production of impulse noise. CONSTITUTION:A DC power supply superimposed with an AC signal is supplied from an intra-station equipment to a subscriber's equipment through 2-wire metallic subscriber lines 11,12. A switch section 32 closes or interrupts either of the 2-wire metallic subscriber lines 11, 12 and a capacitor C1 for AC signal separation in a DC AC separation circuit 21. A voltage monitor section 31 closes the switch section 32 when the voltage between the 2-wire metallic subscriber lines 11, 12 is a prescribed voltage or over and interrupts the switch section 32 when less than the prescribed voltage.