Content in the EDUCATION category

Content (e.g. blog posts, information pages, and files/links) about the activities of the RRRA Education Committee and educational topics of general interest.


The Doctor is In: Continuous Tone-Coded Squelch System

“In radio or wireless telephony, Private Line is a term trademarked by Motorola to describe their implementation of Continuous Tone-Coded Squelch System (CTCSS), a method of using low-frequency subaudible tones to share a single radio channel among multiple users.” [ 1 ]

Learn about the technical background of this squelch tone system in the CTCSS, DTMF and More episode of the ARRL The Doctor is in podcast.