HARRIS CORPORATION M7200VTAC 사용자 설명서

다운로드
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MM-011553-001 
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Talk group selection  
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Talk group scanning  
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Call preemption of the portable and mobile radio clients (e.g., by the Scene Commander)  
The V-TAC takes advantage of OpenSky’s TDMA capability to minimize 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. However, unlike OpenSky 
network radio channels, Extended Coverage supports only one active voice call at a time.  
Frequency selection is automatic from a predetermined list of channels. This list is defined as part of the 
configuration being available for V-TAC operation. The process is supported by GPS location 
information that allows the V-TAC to be aware of its location and choose accordingly from its channel 
list. If no Extended Coverage channels have been configured, the V-TAC will remain in Extended 
Coverage mode and it will continue to search its V-TAC channel list.  
Changing 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 utilize when transitioning from the Mobile-Only mode. Therefore, they also determine 
the access method that must be employed at 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 will take effect.  
However, both the V-TAC and the portable radios can manually override this command-determined 
default mode. At the V-TAC, this is accomplished by a selection from the “Vmode Menu”. Manual 
override at a portable radio is accomplished by pressing a pre-defined key sequence; refer to the 
respective portable radio’s operator manual for exact key sequences required. 
Additional XCOV-TG Mode Information  
The talk group used for Extended Coverage for talk groups (XCOV-TG) communications is the talk 
group that was selected at the V-TAC when it entered XCOV-TG mode.  
However, at the V-TAC, the selected talk group and/or profile can be changed to another talk group 
and/or profile when XCOV-TG is in use. The selected talk group and profile in effect when the V-TAC 
transitioned to XCOV-TG mode will continue to be used to validate portable radio connections and filter 
the network voice traffic sent to the portable radios.  
The selected talk group and profile in use when the V-TAC transitioned to XCOV-TG mode is displayed 
on the bottom line of the dwell menu preceded by an “X-”.  
6.34.2 
V-TAC GPS Interlock  
The V-TAC GPS Interlock feature is enabled or disabled through programming by the system 
administrator. If enabled, the V-TAC can transition from XCOV or XCOV-TG to the Mobile Radio mode 
of operation based on the location and velocity of the VTAC (provided by GPS) in order to prevent a 
rolling VTAC. This capability applies only to XCOV and XCOV-TG mode of operation and does not 
apply to Mobile Radio mode or Scene of Incident (SOI) mode.  
 
The distance and velocity required for transition are programmed by the system 
administrator. 
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