CONVENTIONAL FEATURES
While the PTT switch is pressed, the receiver is enabled so that activity on the channel can be monitored. The PTT switch must be released and then pressed again to make another call attempt. Occasion- ally, a busy condition may be detected even though no one is talking. To key the transmitter in this case, release the PTT switch and then immedi- ately press it again.
There is also a programmable option with this feature to allow trans- mitting with a busy channel if the correct Call Guard signal is detected. The Transmit Disable On Busy feature is enabled or disabled on each conventional group by system operator programming. If this feature is disabled, the transmitter will key even if the group is busy.
Talk-Around
Normally, all transmissions go through a repeater which usually increases range because the repeater transmits at a higher power level and has a higher antenna. However, this means that if you are out of radio range of the repeater, you cannot talk to anyone even if the mobile you are calling is only a short distance away. To allow communication if this occurs,
Call Guard Squelch
The Call Guard squelch feature eliminates distracting messages intended for others using the channel. This is done by using a subaudible tone or digital code to control the squelch. This tone or code is unique to a user or a group on that channel. It is transmitted with the voice signal but is not heard because it is in the subaudible range and attenuated by a filter. Call Guard squelch can be programmed on each conventional group. LTR- Net and LTR operation uses ID codes to perform a similar function.
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