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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 950 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.
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 ...