Page 83 - Radio BEG-engelsk- engelsk tekst
P. 83

© Henning Bach Andersen


               If you count, you will find that we have 8 oscillations.


               Below these you can read that the 8 oscillations take 1 second. This means that

               the frequency is 8 Hz.

                       The wavelength is 300,000 km / 8 = 37,500 km




               Now  we  can  start  looking  at  something  more  advanced.  Let's  calculate  the

               wavelength of Herning Radio's frequency.




               According to the VFG, the frequency is 121MHz. It must be converted to Hz.


               We convert the propagation length of 300,000 km to meters.

               The calculation then becomes:                                       1 KHz  = 1000 Hz
                                                                                   1 MHz = 1.000.000 Hz
                        300,000*1000 m/121,000,000 hz = 2.48m                      1 GHz  = 1000 MHz





               The wavelength is a good thing to know if you are going to make an antenna for
               your radio. You halve the length found until you have an acceptable size.


               Radio amateurs name their transmission range based on the wavelength, and

               they can, for example, talk about the 2 meter band. Then you can calculate the

               frequency yourself!



               There are names for the different frequencies.


                   3 –          30 kHz       VLF       Very Low Frequencies

                 30 -        300 kHz          LF       Low Frequencies

               300 -      3000 kHz        MF       Medium Frequencies

                   3 -          30 mHz        HF       High Frequencies

                 30 -        300 mHz      VHF      Very High Frequencies

               300 -      3000 mHz     UHF      Ultra High Frequencies

                   3 -           30 gHz       SHF       Super High Frequencies

                 30 -         300 gHz      EHF       Extreme High Frequencies
               BEG-english radio marts 2026           -            Midtjysk Flyveskole                    83
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