MIDLAND 203 - Manual (Page 8)

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REAR PANEL
9. Antenna connector: PL connector type
10. EXT SPKR jack: external loudspeaker jack.(the internal loudspeaker will be ex-
cluded)
11. Power supply cable: power 12,6V DC
MICROPHONE
1. PTT: transmission button
2. 4 pin microphone connector
INSTALLATION
An extremely important requirement is the ease of installation and removal for
those occasions when you might want to remove the unit for service and main-
tenance.
The most common mounting position for a transceiver is under the dashboard
directly over the drive shaft hump. Do not mount the transceiver in the path of the
heater or air conditioning.
Take your time and plan your installation carefully. When you have determined
the best location for mounting, use the mounting bracket as a template to mark
mounting holes. Take care when you drill the holes that you do not drill into wiring,
trim or other accessories.
Mount in position with bolts, lock washers and nuts or self-threading screws.
Insert the power cable with lighter plug into the vehicle’s cigarette lighter cord.
Before operating, you must install and connect your antenna system. The lead
from the antenna you’ve installed should be connected to the antenna coaxial
connector. If you are using an external speaker, connect it to the EXT-SPKR jack.
INSTALLING AN ANTENNA
A mobile antenna system is not limited to the antenna only. The transmission line,
as well as the vehicle, are important factors in the total antenna system. Therefore,
you must use the correct type of transmission line and mount the antenna secu-
rely in a position that will give you optimal results.
Use coaxial cable with an impedance of 50 Ohms. Generally speaking, you should
keep the length of the transmission line to a minimum.
The above discussion is as important for reception as it is for the transmission. If
a mismatch exists between the antenna and the receiver, the excellent sensitivity
and signal-to-noise radio of the receiver circuit will be defeated.
Useful information
1. Place the antenna as high as possible
2. The longer the antenna is, the better will be the performance
3. Mount the antenna and keep antenna cable away from noise sources, such as
the ignition switch, gauges, etc.
4. Make sure you have a solid metal-to-metal ground connection.
5. Prevent cable damage during antenna installation.
There are many types of mobile CB antennas: a full quarter-wave length whip, a center
loaded whip, top loaded whip and the base loaded type. For a greater efficiency it is
recommended 2.5 m long, full quarter-wave whip. Antenna length is directly related
to efficiency.