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Antenna
In any radio system an effective antenna installation is essential. Because of the
need to reduce the size of HF antennas so that they can be fitted to a vehicle,
mobile antenna bandwidth becomes quite narrow and hence tuning is critical. In
most cases the only tuning adjustment that can be effected is adjustment to
position. Particular attention must be given to the antenna position if satisfactory
performance is to be obtained. Refer to the instructions supplied with the antenna
you have selected.
Antenna Mounting
The antenna mounting must provide a strong secure anchorage for the base of the
antenna. To obtain maximum radiation, the antenna base
must
be well bonded
electrically to the vehicle chassis. Paint, dirt, rust, etc. should be removed from the
respective fixing points. The mounting point must provide a low resistance
electrical path to the main vehicle metallic structure.
Antenna Feed Cables
Antenna feed cables should be run (as far as possible) away from other vehicle
wiring and especially away from ignition high tension wiring. Where passing
through body panels or internal bulkheads, grommets must be used to protect the
cables. Water-proof connectors must be used when they are outside the vehicle.
Voltage Standing Wave Ratio (VSWR)
After installation it is recommended that the VSWR of the antenna should be
measured for each channel. The instructions supplied with the antenna selected
will detail this operation.
Содержание 2050
Страница 31: ...31 of 285 then press the key ...
Страница 66: ...66 of 285 then press the key type in your messages using the alpha numeric keys then press the key ...
Страница 91: ...91 of 285 use the Scroll keys to select Yes to erase the address book entry then press the key ...
Страница 93: ...93 of 285 enter the telephone number using the numeric keys up to 16 digits then press the key ...
Страница 99: ...99 of 285 then press key to save the new alias ...
Страница 110: ...110 of 285 Add an Entry press the key type in a new label using the Alpha keys then press the key ...
Страница 118: ...118 of 285 Upload pack See section Cloning programming from another transceiver ...
Страница 134: ...134 of 285 then press the key Change the Selcall format associated with the ID if required then press the key ...
Страница 172: ...172 of 285 If the operator attempts to change channels while linked the following screen is shown ...
Страница 175: ...175 of 285 If the operator attempts to change channels while linked the following screen is shown ...
Страница 186: ...186 of 285 Press the key and the first address that matches or the closest match the prefix entered is selected ...
Страница 189: ...189 of 285 Pressing the key displays the link status Or if you already have a link established ...
Страница 224: ...224 of 285 Fitting the 2050 Into the 2040 Manpack Adaptor Removing the Battery Cartridge ...