Television signal is energy, and it travels through the air from the transmitter to the antenna – ideally in a straight line. Each channel has a unique signal. The TV recognises the signal when you put your tv on the right channel number and bingo there is the picture. The signal has been correctly matched to the right channel. That is why the quality of tuners within the TV sets is so important. Poor tuners do this job very badly often not even recognising signal and reporting back to you “no signal” in the case of digital and very snowy pictures if viewing on an analogue TV set.
Television signal should flow smoothly from the air to the antenna and then to the cable and connections. If it does not flow properly the energy (signal) will ridge or disperse – often called harmonics or standing waves. When this happens the noise level in the signal increases and when the noise is greater than the flowing signal your TV does not work.
The TV antenna is designed for the channels it has to pick up. Let’s take Melbourne as an example. Prior to digitals the channels used were 2, 7, 9, 10 and 28. So the antennas were all designed to receive this signal (energy) The only thing that happened when digital was introduced was a shift in channels. 2 became 12 7 became 6 9 became 8 10 became 11 The antenna design has to address a different set of channels and those channels could be analogue or digital it would matter to an antenna.
However, if you are a caravanner you have to address any channel from 0 through to 12 VHF and 28 through to 69 UHF. A caravan antenna is unique as it has to work on 50 plus channels and the design has to meet all the different signal needs. A very difficult task so compromises happen but if you are smart you compromise where there are less channels not where there are more.
Sally Garden
Founder and CEO.
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