40
Installing the Radio
TM9300/TM9400 Installation Guide
© Tait Limited
December 2015
4.12 Checking the Installation
Warning
Danger of fire! The radio’s protection mechanisms
rely on the correct fuses on both the negative and positive power
supply leads being present. Failure to fit the correct fuses may
result in fire or damage to the radio.
The correct fuse types are:
■
30-50W radios: 20A fuses (Tait part number 265-00010-81)
■
25W radios: 10A fuses (Tait part number 265-00010-80)
1.
Insert the fuses into the power leads.
2.
Switch on the radio to confirm that it is operational, but do not
transmit.
3.
Connect an in-line power meter between the radio and the antenna.
4.
TM9300 only:
TM9300 TDMA digital channels do not give a true
power level reading on an in-line power meter. Change to
conventional mode and select an analog channel. For example, select
Change Mode from the radio’s main menu, or Change Mode may
have been programmed to a function key.
5.
Transmit and measure the forward and reflected power levels.
Less than 4% of the forward power should be reflected. If this is not
achieved, check the installation, including the antenna length.
6.
Start reducing the length of the antenna in steps of 0.1 inches to
0.2 inches (2 to 5 mm). Measure the power levels at each step.
Notice
Some antennas are pre-tuned and must not be cut. Check with
the manufacturers’ instructions.
7.
Once the reflected power levels are within tolerance, return the radio
to the required operational mode, then make a call to another party
on the radio.
4.13 Checking the Vehicle After Installation
Complete a post-installation check of all vehicular functions.
25W
