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Night
The sun is lower, ionosphere is lower, best frequency to use is lower
A to B - Possible optimum working frequency is 3 MHz
A to C - Possible optimum working frequency is between 5
- 7 MHz
A to D - Possible optimum working frequency is between 9 -12 MHz
Factors Which Affect HF/SSB Communications
There are a number of different factors which will affect the success of your
communications via HF/SSB radio. These are outlined below:-
Frequency Selection
Frequency selection is perhaps the most important factor that will determine the
success of your HF/SSB communications.
Generally speaking the greater the distance over which you want to communicate,
the higher the frequency you should use.
Beacon Call, a Selcall (Selective Call) function built into the Barrett transceiver,
makes finding the correct frequency to use easy. Beacon Call is based on the
network transceivers all having a selection of frequencies that will accommodate
most ionospheric conditions. When in standby the network transceivers scan these
frequencies waiting for a call (Selcall or Beacon Call) from another transceiver. The
transceiver wishing to check for the best frequency to operate on sends a Beacon
Call to the station he wishes to contact. If his call to the other station is successful
he will hear a revertive call from the station he is calling, indicating the channel he
selected was suitable for the ionospheric conditions prevailing. If he does not hear
this revertive call or it is very weak, he tries on another channel until a revertive call
of satisfactory signal strength is heard.
(Refer to Selcall (Selective Call) section of this manual for full details on Beacon
Call 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 ...