4
INSTALLATION
1. Contents
Unpack and inspect your Magnum 1 for missing or
damaged components. Your MAGNUM 1 includes
the following items:
Quantity
Description
1
MAGNUM 1 Transceiver
1
Stock Microphone
1
DC Power Cord with Inline Fuse
1
Mounting Bracket with Hardware
1
Microphone Hanger with Hardware Set
1
Operating Manual with Schematic
1
Warranty Registration Form
2. Microphone Hanger
The microphone hanger comes with mounting screws
and may be attached to any convenient location.
3. Mounting
When attaching the MAGNUM 1 mounting bracket to
the vehicle, choose a location that will provide easy
access to all front panel controls and air circulation to
the rear panel. When selecting a mounting location,
make sure that there is ample space behind the unit
for the cables. Do not pinch, or bend sharply, the
power or antenna cables. Do not install the MAGNUM
1 in any compartment that restricts airflow and do not
install in a location that interferes with the safe
operation of the vehicle.
Attach the mounting bracket to the vehicle first then
mount the MAGNUM 1 to the bracket. If the rear panel
is not accessible you may want to attach the power
and antenna cable prior to mounting.
4. Electrical Connections
The MAGNUM 1 is designed to work on any 12 - 13.8
volt DC, negative ground, source. The condition of a
vehicle’s electrical system can affect operation. A low
battery, worn generator/alternator, or poor voltage
regulator will seriously impair the performance of the
transceiver. Any of the above conditions could result
in a high level of receiver noise generation or a
substantial loss of the transmitter’s RF output. Make
sure that all of these components of your vehicle’s
electrical system are in good condition prior to
installing the transceiver.
CAUTION!
VOLTAGE EXCEEDING 16 VDC WILL DAMAGE
THE RADIO. MEASURE VOLTAGE AT BATTERY
TERMINALS, WITH VEHICLE RUNNING, PRIOR
TO INSTALLATION!
Before making any electrical connections make sure
the volume (VOL) control is in the “OFF” position.
Connect the positive (+) red wire of the DC power
cord to a positive 13.8 volt source at the vehicle fuse
block. If connecting to the fuse block, it is
recommended that a switched power source is used
so that the power to the transceiver is disconnected
when the vehicle is off. This will eliminate the
possibility of the transceiver draining the vehicle’s
battery.
Connect the negative (-) black wire to a metal part of
the vehicle’s frame, or chassis ground. Make sure that
this is a good ground connection.
The MAGNUM 1 power cord may also be connected
directly to the battery. Connecting directly to the
battery has several benefits, the first of which is to
maximize RF output. Secondly, the battery is a very
large capacitor and will help eliminate certain types of
ambient and vehicle noise. If connecting directly to
the vehicle’s battery, additional power cable may be
required. On runs of 8 feet or less use 12-gauge
stranded wire. Use 10-gauge wire on longer runs.
5. Antenna Connection
The transceiver will operate using any standard 50-
ohm ground-plane, vertical, mobile whip, long wire or
similar antenna. The antenna should be rated at 100
watts PEP minimum. A standard SO-239 type
antenna connector is located on the rear panel of the
MAGNUM 1. Connection is made using a PL-259 and
high-grade coaxial cable (RG213, RG58A/U or Mini
RG-8 is recommended).
A ground-plane antenna provides greater coverage
and is recommended for fixed station-to-mobile
operation. For point-to-point fixed station operation, a
directional beam antenna operates at greater
distances even under adverse conditions. A non-
directional antenna should be used in a mobile
installation; a vertical whip is best suited for this
purpose. The base loaded whip antenna normally
provides effective communications. For greater range
and more reliable operation, a full quarter wave whip
may be used. Either of these antennas uses the metal
vehicle body as a ground plane.
Once the antenna is mounted on the vehicle, route
the coaxial cable so that it is not next to any power
cables or vehicle cables. Connect the PL-259 to the
antenna connector on the rear panel of the MAGNUM
1. Make sure that the cable does not interfere with the
safe operation of the vehicle.
6. VSWR
Before use, it is important to determine the antenna
system’s VSWR (voltage standing wave ratio). You
will need a high quality SWR bridge (meter) to
accurately tune your antenna system. First, make
sure the SWR bridge is in good working order and is
calibrated. To ensure your radio is performing
properly the VSWR should never exceed 1.5 to 1.
Never transmit on any antenna system where the
VSWR exceeds 1.8 to 1. This will stress the output
stage and could destroy the RF transistors; this type
of misuse and failure is not covered under warranty.
