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(Refer to Selcall (Selective Call) section of this manual for full details on Beacon
Call operation.)
Time of Day
As a rule, the higher the sun, the higher the frequency that should be used. This
means that you will generally use a low frequency to communicate early morning,
late afternoon and evening, but you will use a higher frequency to cover the same
distance during times when the sun is high in the sky (e.g. midday). You will need
to observe the above rule carefully if your transceiver has a limited number of
frequencies programmed into it, as you may only be able to communicate
effectively at certain times of the day.
Weather Conditions
Certain weather conditions will also affect HF/SSB communications. Stormy
conditions will increase the background noise as a result of ‘static’ caused by
lightning. This background noise could rise to a level that will blank out the signals
you are trying to receive.
Man-made Electrical Interference
Interference of an electrical nature can be caused by overhanging power lines, high
power generators, air-conditioners, thermostats, refrigerators and vehicle engines,
when in close proximity to your antenna. The result of such interference may cause
a continuous or intermittent increase in the level of background noise.
System Configuration and Installation
The method in which your system is configured and installed will also affect the
success of your HF/SSB communications. Your choice of antenna system and
power supply is critical. Correct installation is also extremely important. An HF/SSB
transceiver is generally installed using different rules to those used to install VHF or
UHF transceivers. Failure to correctly install an HF/SSB system will greatly affect
the communications quality you will obtain. Refer to the installation section of this
manual for details.
Your local Barrett representative will be able to assist with your system
configuration and/or installation.
Special Note - HF Communications Compared with VHF or UHF Short Distance
Communications
Communications on any HF/SSB transceiver will sound different to that on a VHF
(Very High Frequency) radio or UHF (Ultra High Frequency) radio or telephone.
This is because of the nature of HF propagation and the modulation methods used.
On HF/SSB transceivers there will always be background noise evident behind the
signal you are receiving and this will increase when there is electrical interference
or thunderstorm activity in the area.
Содержание 2090
Страница 33: ...33 of 246 then press the key ...
Страница 35: ...35 of 246 then press the key or press the key and the last station called will be called again ...
Страница 66: ...66 of 246 then press the key type in your messages using the alpha numeric keys then press the key ...
Страница 90: ...90 of 246 use the Scroll keys to select Yes to erase the address book entry then press the key ...
Страница 92: ...92 of 246 enter the telephone number using the numeric keys up to 16 digits then press the key ...
Страница 94: ...94 of 246 enter the new telephone number using the numeric keys up to 16 digits then press the key ...
Страница 96: ...96 of 246 then press the key ...
Страница 99: ...99 of 246 then press key to save the new alias ...
Страница 109: ...109 of 246 Add an Entry press the key type in a new label using the Alpha keys then press the key ...
Страница 116: ...116 of 246 Upload Pack See section Cloning programming from another transceiver ...
Страница 124: ...124 of 246 then press the key ...
Страница 134: ...134 of 246 then press the key Change the Selcall format associated with the ID if required then press the key ...
Страница 183: ...183 of 246 Pressing the key displays the link status Or if more than one link is in progress example 3 links ...
Страница 217: ...217 of 246 Using the numeric keypad enter Six digit ID and press the key then press the key to proceed with cloning ...
Страница 220: ...220 of 246 Rapid Deployment Hand Crank Generator P N 2090 03 04 ...
Страница 222: ...222 of 246 ...
Страница 223: ...223 of 246 Rapid Deployment Hand Crank Generator P N 2090 03 04 ...