Antenna Connection - Kenwood TM-251A Instruction Manual

Note:
» For your transceiver to fully exhibit its performance capabilities,
the following optional power supply is recommended:
PS-33 (20.5 A, 25% duty cycle).
» Before connecting the DC power supply to the transceiver, be
sure to switch the transceiver and the DC power supply off.
> Do not plug the DC power supply into an AC outlet until you make
all connections.
m Replacing Fuses
If the fuse blows, determine the cause then correct
the problem. After the problem is resolved, only then
replace the fuse. If newly installed fuses continue to
blow, disconnect the power plug and contact your
dealer or nearest Service Center for assistance.
Fuse Location Fuse Current Rating
TM-251NVE 15A
TM-451NVE 10A
Supplied Accessory 20A
DC Power Cable
CAUTION: Only use fuses of the specified type and rating.
ANTENNA CONNECTION
The type of the antenna system, consisting of the
antenna, ground, and feed line, will greatly affect the
successful performance of the transceiver. Use a
properly adjusted 50 ohm antenna of good quality
designed for operation at your operating frequency to let
your transceiver perform at its best.
Install low-loss 50 ohm coaxial cable and a first quality
connector for the connection to the transceiver. For
longer feed line runs, especially for operation at UHF
frequencies, you might consider investing in "hardline"
transmission line. Hardline is available in larger
diameters and has much lower loss than coaxial cable.
The lower loss can make a significant difference for
those interested in weak signal operation. In all cases,
match the impedance of the feed line and antenna so
that the SWR is minimum. Generally, an SWR
measurement of 1.5:1 or less is considered satisfactory.
All connections must be clean and tight. Coupling the
antenna to the transceiver via feed line having an
impedance other than 50 ohms reduces the efficiency of
the antenna system. It also can cause interference to
nearby broadcast television receivers, radio receivers,
and other electronic equipment.
CAUTION:
> All fixed stations should be equipped with a lightning arrester to
reduce the risk of fire, electric shock, and transceiver damage.
> Transmitting without first connecting an antenna or other
matched load may damage the transceiver. Always connect the
antenna to the transceiver before transmitting.