This article covers VHF and UHF TV reception.
The transmission and reception of TV signals is affected by many variables. Atmospheric moisture, solar activity, physical obstructions such as mountains and buildings, and time of day will all have an effect on the signal transmission and deterioration of signal reception.
TV transmission is sent on two types of frequency – VHF and UHF. The VHF, low band frequency, is often used in country areas to send TV signal to a large area. The UHF transmission is used mainly in ‘local’ (one town) areas. How far the transmission is sent depends on the power of the transmitter (eg, the Canberra transmission is sent 130kms but the Barcaldine, Qld, transmitter sends it 11kms).
UHF transmission and reception can change as the atmosphere warms and cools throughout the day. The main advantage of UHF transmission is the physically short wave that is produced by the high frequency. The UHF antenna is stubby and short. The major disadvantage of UHF is its limited broadcast range and reception, often referred to as line-of-sight between the TV station’s transmission antenna and customer’s reception antenna, as opposed to VHF’s very long broadcast range and reception which is less restricted by line-of-sight.
Now what does that mean to the traveller? It means that to get the best reception, your antenna needs to have both a UHF antenna (small) as well as a VHF antenna (large).
* All capital cities have VHF reception needing a big antenna.
* Nearly 90% of transmission in Australia comes on the UHF frequency.