| 摘要 |
<p>Excluder device for telephones installed in parallel, characterised in that it basically consists of a combination of a full wave bridge rectifier (1) with a relay circuit, made up of a zener diode (2) and a current divider consisting of two resistors (3, 4) the relay circuit being associated with a thyristor (5), whose anode is connected to the cathode of the zener diode and to the positive of the rectifier (1), whilst the cathode is connected to earth and the switch to the current divider, and in that an independent resistor is incorporated, able to cause a voltage drop equivalent to that which determines the rest of the telephone system.</p> |
