7
Rev. (5-20)
19.6 CLOSE PROXIMITY OF 800 MHZ RADIOS
The Department of Transportation is recommending the following procedures for communicating with other
units that are in close proximity. These locations may be plow trains for snow removal and small work zones.
These 800 MHz radios are designed and have the capability of transmitting and receiving “On” and “Off” the
radio network.
1.
“On” network describes the actual use of the 800 MHz network. Secure communications are
transmitted and received through high profile towers and microcell sites. Standardized voice groups
are defined and should be utilized for proper communication channels.
2.
“Off” network describes the basic use of low band radio waves for communicating.
A. The “Off” network is from one radio antenna to another radio antenna.
B. The typical range is your line of sight up to a maximum of two miles.
C. A limiting factor is the geography of the land.
3.
Communication links between “On” and “Off” network do not exist.
A. Thus, only personnel transmitting/receiving “On” the network shall communicate with others
that are “On” the network.
B. Those personnel transmitting/receiving “Off” the network shall communicate with others that are
“Off” the network.
C. As a suggestion, managers and/or supervisors should be notified when personnel have the need
to talk “Off” network.
PROCEDURES FOR PROGRAMMING MOBILE RADIOS “OFF” NETWORK:
1.
Notify manager/supervisor of the need to leave the “On” network, identify the “Off” network
frequency to be used and coordinate the move with other members of your work group.
2.
Press the “C” button on the 800 MHz display screen.
3.
Once “Off” network, press the right or left arrow buttons to scroll to the designated channel.
PROCEDURES FOR PROGRAMMING MOBILE RADIOS “ON” NETWORK:
1.
Notify others when leaving the “Off” network channel.
2.
Press the “C” button on the 800 MHz display screen.
3.
Once “On” network, press the pre- programmed “A” or “B” buttons or use the right or left arrow
buttons to scroll to the designated voice group.
4.
Notify manager/supervisor that you are back “On” network.
PROCEDURES FOR PROGRAMMING PORTABLES (HAND HELD) RADIOS “OFF”
NETWORK:
1.
Notify manager/supervisor of the need to leave the “On” network, identify the “Off” network
frequency to be used and coordinate the move with other members of your work group.
2.
Press the “A” or “B” button on the top of the portable near the display screen until you see
“SELMODE” (select mode) on the display screen.
3.
Quickly press the “Up” or “Down” button on the side near the “Press-to-Talk” button, keep pressing
either button until you see “OCF” (OpenSky Conventional FM) on the display screen.
PUB 23 - MAINTENANCE MANUAL Chapter 19: Radios
