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9.
Scan
This is an alternate action switch. Pressing the key the first time starts the scan and
pressing it again stops the scan.
The purpose of the scan function is to allow the user to monitor multiple channels and
stop at the channel that is active. This would be useful for a supervisor who needs to
monitor the activity among different groups of users.
The scan function requires the user to program a scan list. This is a list of the channels
that you want to scan. If during the scan, the system acquires an active channel, the
system will stop at that channel until the activity on that channel disappears. There is a
time delay from the time the signal will disappear until the system will start scanning the
next channel. If the channel becomes active before the system starts to actually change
the channel, then that channel will become active again.
It is possible to select one of the channels as a priority channel. When a priority channel
is selected, then when the system scans, the priority channel will be checked at every
other scan. As an example, let’s assume you have three channels and the first one is a
priority channel. The scan sequence will be channel 1, channel 2, channel 1, channel 3,
channel 1, channel 2, and so on. As part of the priority scan, there is a “look back”
function. If the system stays at a non priority channel, then every so often, defined as the
look back period, the system will check the priority channel to determine if there is any
activity. If there is activity on the priority channel, the system will lock into the priority
channel until the activity on the priority channel disappears.
The next question that has to be answered is what the system does when you want to
transmit and it is in the scan mode. For this function we provided many options.
Selected Channel
: Selecting this option will cause the radio to transmit on the channel
specified by the channel selector switch.
Selected C Current Channel
If the radio is not locked on to a channel, then selecting this option will cause the radio to
transmit on the channel specified by the channel selector switch when the PTT switch is
pressed. If the radio is locked on to a channel, then selecting this option will cause the
radio to transmit on that current channel when the PTT switch is pressed.
Last Rx Channel
If this option is selected, then the radio will transmit on the last channel received that is
part of the scan list when the PTT switch is pressed.
Last Tx C Current Channel
If the radio is not locked on to a channel, then selecting this option will cause the radio to
transmit on the last channel it transmitted that was part of the scan list when the PTT
switch is pressed. If the radio is locked on to a channel, then selecting this option will
cause the radio to transmit on that current channel when the PTT switch is pressed.
