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[QUOTE=&quot;serndipity, post: 52555, member: 5125&quot;]The purpose of an antenna tuner is to match the signal source and load impedances. This is done because the maximum signal (i.e. power) transfer occurs when the signal source (i.e. antenna), load (i.e. TV) and any transmission line (i.e. coax) are all of the same characteristic impedance.However, while the losses due to mismatches can be profound, an antenna tuner would not be an appropriate solution for TV reception.First of all, the load impedance (i.e. TV) is fixed at 75 ohms. The variable is the impedance of the source (i.e. antenna). This means that the tuner must be located at this point and adjusted for each channel (e.g. typically not practical or convenient). Because TV signals can be transmitted in 3 very different groups of frequencies (e.g. VHF-low, VHF-high and UHF) and antennas are frequency dependent, the design of a tuner to cover this range of frequencies would not likely be realizable (e.g. far be complex, challenging consruction and expensive).Fortunately, antennas have been developed that will present a near constant source impedance and gain over a very wide range of frequencies. With a load/source&nbsp; mismatch of typically less than 2:1, the losses would be no more than 1/2 dB (i.e. insufficient).The CM4228 is a UHF antenna. Initially, I thought you meant that you wanted to tune it to receive VHF channels. However, from the graphs in the link below, you may only be trying to improve it's gain within the UHF band.<a href="http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html">Temporary page</a>It appears that there is an easier, practical solutionAnother link that may be of interest is:<a href="http://www.hdtvprimer.com/ANTENNAS/cm4228.html">Channel Master 4228</a>[/QUOTE]

[QUOTE="serndipity, post: 52555, member: 5125"]The purpose of an antenna tuner is to match the signal source and load impedances. This is done because the maximum signal (i.e. power) transfer occurs when the signal source (i.e. antenna), load (i.e. TV) and any transmission line (i.e. coax) are all of the same characteristic impedance. However, while the losses due to mismatches can be profound, an antenna tuner would not be an appropriate solution for TV reception. First of all, the load impedance (i.e. TV) is fixed at 75 ohms. The variable is the impedance of the source (i.e. antenna). This means that the tuner must be located at this point and adjusted for each channel (e.g. typically not practical or convenient). Because TV signals can be transmitted in 3 very different groups of frequencies (e.g. VHF-low, VHF-high and UHF) and antennas are frequency dependent, the design of a tuner to cover this range of frequencies would not likely be realizable (e.g. far be complex, challenging consruction and expensive). Fortunately, antennas have been developed that will present a near constant source impedance and gain over a very wide range of frequencies. With a load/source mismatch of typically less than 2:1, the losses would be no more than 1/2 dB (i.e. insufficient). The CM4228 is a UHF antenna. Initially, I thought you meant that you wanted to tune it to receive VHF channels. However, from the graphs in the link below, you may only be trying to improve it's gain within the UHF band. [url=http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html]Temporary page[/url] It appears that there is an easier, practical solution Another link that may be of interest is: [url=http://www.hdtvprimer.com/ANTENNAS/cm4228.html]Channel Master 4228[/url][/QUOTE]

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