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<blockquote data-quote="Carlos" data-source="post: 49718" data-attributes="member: 176537">Hi Chris, this is really a follow up to my other postings on this whole subject of re-transmission and the more I read the more intriguing it gets!&nbsp; I have been told that although the frequencies are different for each transmitter they are nevertheless all microwave frequencies over 10GHz and mostly use log periodic antennas for reception.&nbsp; This fascinates me as the most commonly used antenna is a Band&nbsp; 4 &amp; 5 covering the frequency range of 470 to 900 MHz which is of course well below 10GHz so is the type of antenna used not especially important and if not would a high gain Yagi such as the DAT45 work better in poor reception areas or is the 'balun' frequency matched and therefore rendering the Yagi useless (the Log Periodic does not need a 'balun' as its impedance is close to 75 ohm).Also because there is no LNB to convert the signal to a lower frequency the signal from the antenna travels down the cable at its receiving frequency.&nbsp; As I understand it, the higher the frequency, the higher the cable loss and in fact this is the main reason the LNB converts the frequency to a lower one.&nbsp; Actually I think it 'chops off' about 9GHz so the ongoing signal is circa 1.5GHz.&nbsp; I am told the set top box software is modified to bypass this chopping but it makes the length of the receiving coax critical to receiving a good signal.Any views to enlighten me, Carlos</blockquote>

[QUOTE="Carlos, post: 49718, member: 176537"] Hi Chris, this is really a follow up to my other postings on this whole subject of re-transmission and the more I read the more intriguing it gets! I have been told that although the frequencies are different for each transmitter they are nevertheless all microwave frequencies over 10GHz and mostly use log periodic antennas for reception. This fascinates me as the most commonly used antenna is a Band 4 & 5 covering the frequency range of 470 to 900 MHz which is of course well below 10GHz so is the type of antenna used not especially important and if not would a high gain Yagi such as the DAT45 work better in poor reception areas or is the 'balun' frequency matched and therefore rendering the Yagi useless (the Log Periodic does not need a 'balun' as its impedance is close to 75 ohm). Also because there is no LNB to convert the signal to a lower frequency the signal from the antenna travels down the cable at its receiving frequency. As I understand it, the higher the frequency, the higher the cable loss and in fact this is the main reason the LNB converts the frequency to a lower one. Actually I think it 'chops off' about 9GHz so the ongoing signal is circa 1.5GHz. I am told the set top box software is modified to bypass this chopping but it makes the length of the receiving coax critical to receiving a good signal. Any views to enlighten me, Carlos [/QUOTE]

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