Tyco Electronics MM102014V1 - Manual (Page 52)

MM102014V1, Rev. G
When the VTAC transitions from XCOV or XCOV TG mode to Mobile Radio mode, an audio and visual
indication is provided to the operator. This indication is identical to the indication of the mode transition
based on the external event switch.
When the VTAC is in Mobile Radio mode, the VTAC can return to XCOV or XCOV TG mode only by
the external event switch or manually via the control head menu.
If the VTAC is in XCOV or XCOV TG mode and the VTAC transitions to Mobile Radio due to
exceeding the distance and velocity thresholds, the VTAC will not transition back into XCOV or XCOV
TG mode when it falls back within the distance or velocity thresholds.
5.23.3 Scene-Of-Incident Mode (“SOI”)
SOI mode is user-selectable using the V-TAC’s, “Vmode Menu.” The SOI mode provides a local
repeater function with no network connection. It supports two concurrent voice calls, and it supports
communication between other mobiles and portables connected to the V-TAC via the SOI mode.
When using the SOI mode, both the V-TAC and any connected portable or mobile
radios (the clients) are off the OpenSky network. Therefore, communications with
radios and dispatch personnel on the network is not possible.
CAUTION
Use the SOI mode only when absolutely necessary and only when its use is approved by
an OpenSky radio system network administrator and/or a scene commander.
The V-TAC’s VRB radio continuously transmits when the V-TAC is in the SOI mode.
Therefore, a V-TAC operating in this mode may cause undesirable interference to other
nearby radios that are not connected to the V-TAC.
Frequency selection is performed manually from a list of pre-defined channels using the V-TAC’s
“Vchan Menu.” The radio indicates the FCC channel number for each, in addition to its alpha-numeric
identifier.
In SOI mode, the V-TAC supports the following features:
• Talk Group selection
• Talk Group scanning
• Call preemption of the client radios (i.e., Scene Commander can preempt a call from a portable or
mobile radio)
In SOI, an emergency initiated at the V-TAC will preempt a client voice call.
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