Recorder actuator for communication lines
作者： Richard W. Williams
DOI:
关键词: Relay 、 Handset 、 Electrical engineering 、 Resistor 、 Engineering 、 Electronic engineering 、 Telephone line 、 Bridge circuit 、 Capacitor 、 Current limiting 、 Solid-state relay
摘要: A connection across telephone lines includes a resistor having shunted capacitor circuit holding normally closed relay open and permitting it to close on closing the circuit, by lifting handset, activate recorder. Replacing handset opens shutting off current limiting resistance in recorder switch prevents damage while provides high for activating solenoid. bridge eliminates polarity of magnetically biased relay.
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