TELEPHONE_LINE_IN_USE_INDICATOR

Published:2009/7/10 23:29:00 Author:May | From:SeekIC

When a telephone line is not in use, about 48 V appears across the line, which drops to about 10 V or less when the line is in use. This circuit switches a bicolor LED as an indicator.



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Electrical_Equipment_Circuit/Telephone-Related_Circuit/TELEPHONE_LINE_IN_USE_INDICATOR.html

Print this Page | Comments | Reading(3)