Continuous Tone-Coded Squelch System
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Revision as of 07:25, 10 January 2005 by Blantonl
The Continuous Tone Coded Squelch System (CTCSS) has been in used in the Land Mobile Radio arena from the late 1960’s. It is known by a number of different trade names such as Private Line® (PL) by Motorola, Channel Guard® (CG) by General Electric and generically as Tone Squelch. It is a use of sub--audible frequency tone is part of the transmission. The land mobile industry started with some 38 sub-audible frequencies this has increased over the years to the more generally accepted 50. There is no generic standard tone number assignment or code letter to go with a particular tone; however, below is a chart of the commonly accepted 50 tones used at this time.
--Lou Maag 14:21, 3 Jan 2005 (EST)