XTCSS Signalling
Developed by CML, XTCSS is a squelch signalling format for radio systems, using both sub-audio (CTCSS) and in-band (XTC) signalling concurrently.
Many CTCSS channels can be employed in a single RF channel. Within the ‘leisure radio’ environment especially there is always the possiblity that other in range users will use the same, standard sub-audio tone, therefore causing interference and loss of privacy.
The implementation of XTCSS, an in-band tone and sub-audio signalling combination, provides, currently, up to 99 additional private channels within the single RF channel. The use of XTCSS signalling prevents ‘squelch breakthrough’ caused by other common-channel users.