ATIS Telecom Glossary
Monday, September 01, 2014

A B C D E F G H I
J K L M N O P Q R
S T U V W X Y Z  
Go
 
Glossary Home
Foreword
Introduction
Normative References
Using the ATIS Telecom Glossary
Annex A: Informative References
 
 
 
<< Back
ringdown
In telephony, a method of signaling an operator in which telephone ringing current is sent over the line to operate a lamp and cause the drop of a self-locking relay. Note 1: Ringdown (a) is used in manual operation, as distinguished from dialing, (b) uses a continuous or pulsed ac signal transmitted over the line, and (c) may be used with or without a switchboard. Note 2: The term "ringdown" originated in magneto telephone signaling in which cranking the magneto in a telephone set would not only "ring" its bell but also cause a lever to fall "down" at the central office switchboard.

 

 

 

 

 

 

 

 

 

 



 
These definitions were prepared by ATIS Committee PRQC
 
For more information on the work related to these definitions,
please visit the ATIS website and the ATIS Document Center