Quote:
Originally Posted by mustefa ubram
hi nicolas
How do you get a frequency 5000hz with telescopic antenna? 
you need 15000meter antenna for this frq?
Please give a little explanation |
Hi OPS
http://www.stormwise.com/index.html
relation_between_frequency_and_distance
Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 kHz to 30 kHz and wavelengths from 10 to 100 kilometres. Since there is not much bandwidth in this band of the radio spectrum, audio (voice) cannot be transmitted, and only low data rate coded signals are used. The VLF band is used for a few radio navigation services, government time radio stations which broadcast time signals to set radio clocks, and for secure military communication. Since VLF waves penetrate about 40 meters into saltwater, they are used for military communication with submarines. Also known as the myriametre band or myriametre wave as the wavelengths range from one to ten myriametres (an obsolete metric unit equal to 10 kilometres).