CTCSS Tones

"CTCSS tones, sometimes called sub codes or privacy channels, uses a sub-audible tone to prevent other people using the same channel from interrupting your conversation.  Most radios have 38 available CTCSS (Continuous Tone Coded Squelch System) codes which can be individually assigned to any of 14 channels, for a total of 532 combinations.

Once activated, the sub-audible tone is transmitted each time the PTT (push-to-talk) button is pressed.  Additionally, the radio only responds to incoming signals using the same CTCSS tone."  The above text was taken from the GE 35840 user's guide.

NOTE:  This feature does not keep anyone from hearing your conversation.  It simply "filters-out" anyone's transmission that does not have the same channel/code combination set. 

Here is a list of the most common CTCSS frequencies used in FRS radios:

NOTE:  Different brands of FRS radios may have different CTCSS tone assignments.