User's Manual

indicator button positions. Field programming determines the exact position. The VRS
requires an ASTRO radio with a remote-mount control head.
Figure 1 Typical ASTRO Control Head with VRS
When the VRS is turned on, the indicator illuminates and, after transmitting the Single
Tone burst, the words "VRS BOTH" (indicating the In-Car Monitor mode) will be
displayed momentarily. The indicator remains on for as long as the VRS is on.
When the VRS unit is activated, it transmits Single Tone on the portable frequency, and
assumes the priority (active) repeater state. The Single Tone frequency is fixed at 847.5
Hz. For proper operation, all VRS units to be used in the same system must be
programmed with the same Single Tone frequency, as well as other VRS and ASTRO
mobile features.
Press the VRS button to disable the VRS option. When the system is turned off and then
back on from the control head, the VRS option returns to the state it was in immediately
before the control head was turned off.
Vehicle Interface Ports
Another method of enabling/disabling the VRS option is through the use of a vehicle
interface port (VIP). The field programmer selects which VIP to use and whether the
input control voltage is to be high/ground or ground/high.
One use of VIP operation connects the VRS switch lead to a portable radio vehicular
control charger, such as the AVA, SVA, MVA, or MTVA. Remove the portable from its
charger pocket to automatically enable the VRS option. Replace the portable unit in its
charger to disable the VRS option. A toggle switch on the portable unit charger allows
the portable unit to be removed without enabling the VRS option.
NOTE: This requires an additional field modification kit, PLN1334A, which is not
included with the VRS.
Turning the portable unit charger off, then on does not disable the VRS option. The VIP
setting controls the on/off state of the VRS option. If the field programmer chooses the
VIP option, pressing the VRS button on the control head will only cause the display to
change momentarily to the In Car Monitor Mode ("VRS BOTH"). It will not enable or
disable the VRS as previously described. It is still necessary, however, to select in
CPSCPS an indicator button for the VRS if it is desired to have the indicator light when
the VRS is enabled.
VRS Access
With the VRS on, press the portable radio's PTT button to begin transmissions. The VRS
programming must include correct PL frequencies to allow the portable unit to access the
option. The
VRS option receives signals with the correct PL, then uses the mobile radio to re-transmit
the signals. The control head's XMIT indicator lights during the re-transmission.
The VRS re-transmits received mobile signals as explained in the "Mobile Audio Repeat"
paragraph on page 7. Note that the XMIT indicator does not light when the VRS is
transmitting to the portable.
To transmit directly to the other portable units, turn off the portable transmit PL. This
allows you to talk around the VRS without transmitting on the mobile channels.