MM23772, Rev. F
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The V-TAC supports two Extended Coverage modes: Extended Coverage for individual users (XCOV)
and Extended Coverage for a talk group (XCOV-TG). Typically, Extended Coverage is used after the
vehicle’s operator has exited the vehicle with a portable radio unit and the portable unit requires this
bridging functionality to access the OpenSky radio network.
The V-TAC takes advantage of OpenSky’s TDMA capability to eliminate interference between its local
and network radio links when operating in an Extended Coverage mode (XCOV or XCOV-TG), an
undesirable characteristic of many traditional vehicular repeater systems. Because the V-TAC employs
this technology, interference on the network and local radio links is minimized.
A V-TAC in XCOV or XCOV-TG mode sends its alias to clients. The alias is displayed in the second line
of the dwell menu of the client, (“VA <alias>”). The client must be connected to a V-TAC running
version OTP14.4 or for the V-TAC to provide the alias to the client. If the client is connected to a V-TAC
running version OTP14.3.1 or earlier, the client displays “VA None.”
8.31.2
Change Between Extended Coverage Modes
By default, the specific Extended Coverage mode utilized, either XCOV or XCOV-TG, is determined by
commands sent to the V-TAC and portable radios from the system administrator or radio installation
personnel. In other words, these commands determine which Extended Coverage mode the V-TAC and
radios normally use and determine the access method that must be employed by a portable radio to
connect to the V-TAC. After commands of this type are sent to the V-TAC and portable radios, each must
be rebooted (powered off and then back on) before the change takes effect.
A radio can manually override this command-determined default mode by entering *61 # or *62 # or by
using the Client Mode menu option. Command *61 # sets the radio to use the XCOV mode and *62 # sets
the radio to use the XCOV-TG mode. However, the connection will only be successful if the V-TAC
operating mode matches the manually selected portable V-TAC mode.
8.31.3
Use the XCOV Mode
The Extended Coverage for individual users (XCOV) mode allows up to eight (8) client radios to connect
to the V-TAC. The radios have full radio functionality including selective calling and mobile data.
With the Extended Coverage for individual users’ mode (XCOV), V-TAC configuration defines which
portable radios are permitted V-TAC access.
Connecting to the V-TAC is automatic or manual, as determined by the system administrator and
configuration. Automatic is the preferred mode.
8.31.3.1 Manually Access the XCOV Mode
P7270 Model Radios Only
:
1.
Enter the command *61 # to set the radio to use the XCOV mode.
2.
Press *60 # to disconnect from the XCOV mode.
P7250 and P7270 Model Radios
1.
Press
or
until the Client Mode menu appears.
2.
Press
or
until XCOV is displayed.
3.
Press
to confirm mode selection. The radio reverts to the dwell display and the V-TAC icon is
displayed.