User's Manual

every 6 seconds is determined by the "temporary message display timer" value. This
value (from 250 to 6250 ms [default = 1000 ms]) can be programmed by the CPS. It is in
the RADIO WIDE DISPLAY OPTIONS screen (D, C, F from the main CPS screen).
Repeater PPI
The Repeater Portable Priority Interrupt (PPI), when enabled, causes a base-to-portable
transmission to be interrupted every 1 second in trunked mode or 2 seconds in
conventional mode so that the repeater can search for a portable radio signal. (These
times are programmable and may be changed to 500ms for trunked or 500ms for
conventional modes). This interruption may be heard on the portable as a "clicking"
noise, but PPI is necessary to give the portable user priority over base-to-portable
transmissions, for the self-clearing function of the automatic priority resolution feature,
and to allow portable users in trunked mode to break in during system hang time to
prevent loss of voice channel. This feature may be disabled through CPS.
Quick-Key
This feature allows the portable user to determine the status of the mobile trunking
system. The feature is initiated by a short press of the portable's PTT that is long enough
for the VRS to key the mobile and access the trunking system, for less than 1 second in
duration.
4. Installation
When selecting the location for the VRS, make certain that there is sufficient clearance
for routing the T-cable and the antenna cable to the front of the unit.
VRS Installation
The standard VRS is installed using the HKN6153A interface cable. The molded DB-25
end connects to the ASTRO front connector. The DB-25 end with the plastic jacket
connects to the VRS (see Figure 2).
Figure 2 Installing the VRS to an ASTRO Mobile
If an external Siren/PA is to be used, the option xxxxAA must be ordered which replaces
the HKN6153A cable with a HKN6154A cable, or a separate HKN6154A cable must be
ordered. To install, plug the "T" side of the HKN6164A cable to the Siren/PA. Replace
the mounting screw on the HKN4363B cable with the double length screw. Plug this side
into the "T" cable. Plug the DB-25 end of the HKN6154A into the VRS (see Figure 3).
Figure 3 Installing the VRS with an External Siren/PA
Mobile Radio Operation and EME Exposure
To assure optimal radio performance and that human exposure to radio frequency
electromagnetic energy is within guidelines referenced earlier in this document, transmit
only when people outside the vehicle are at least the minimum lateral distance away from