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amateur television has gained popularity  as hobbyists adapt inexpensive consumer video electronics like  camcorders and video cards in 
PCs. Because of the wide 
bandwidth and stable signals  required, amateur television is typically found in the 70 cm  (420 MHz–450 MHz) frequency range, though there is also limited use on  33 cm (902 MHz–928 MHz), 23 cm (1240 MHz–1300 MHz) and higher. These  requirements also effectively limit the signal range to between 20 and  60 miles (30 km–100 km). The use of linked 
repeater systems, however, can allow  transmissions across hundreds of miles.
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