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CONVENTIONAL FEATURES
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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, talk-around groups can be programmed which enable direct 
mobile-to-mobile communication without going through a repeater.
Talk-around is then automatically enabled by selecting one of these 
groups. There is no special talk-around option switch or indicator. 
However, the group alpha tag on the lower line of the display may be 
used to indicate groups programmed for this feature. Talk-around is not 
available on LTR-Net and LTR systems.
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.