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[QUOTE=&quot;DW-77, post: 121994, member: 38055&quot;]Ricki,I was able to verify that the Antennas Direct DB2e/4e/8e were re-designed for channels 14 to 50. Therefore, their &quot;bow-ties&quot; and reflectors are slightly larger than their &quot;pre-2009&quot; versions. Antennas Direct also happens to be among the few manufacturers who publish relevant performance data for their products (radiation patterns and gain/VSWR variation with frequency), which I like.On the other hand, Channel Master claims that the CM422x-HD antennas are &quot;designed for HD&quot;, but don't provide any technical data to back up that claim. The CM web page shows contradicting information, stating on one tab that the CM4221-HD is &quot;Designed for UHF/VHF reception from 470 to 700 MHz&quot;, and on a different sub-page: &quot;Reception Range = Channels 14 thru 69&quot;. Different tabs also show inconsistent physical dimensions for this antenna. Asked for clarification via email more than once, but never received an answer. Called, their support team could not sort out the confusion, but said that the CM422x-HD are being sold for more than 5 years.A fair comparison &quot;on paper&quot; becomes pretty difficult, because confusion dominates when it comes to antenna documentation in general. Some manufacturers do not show any actual data, and market their antennas based on &quot;Range&quot; alone (like selling a car based on &quot;how far it can go on a full tank&quot;, while not mentioning fuel mileage, how large the tank is and without saying that the number advertised was obtained driving downhill). There are also antenna makers who only specify &quot;maximum gain&quot;, omitting to say that, by design, gain peaks around 800MHz (outside the current US UHF band). Also, the dBi/dBd gap needs to be accounted for, whenever needed.As you said: manufacturers can publish pretty much whatever numbers they want, it is up to us to figure out when those numbers are relevant (and when they are not).[/QUOTE]

[QUOTE="DW-77, post: 121994, member: 38055"]Ricki, I was able to verify that the Antennas Direct DB2e/4e/8e were re-designed for channels 14 to 50. Therefore, their "bow-ties" and reflectors are slightly larger than their "pre-2009" versions. Antennas Direct also happens to be among the few manufacturers who publish relevant performance data for their products (radiation patterns and gain/VSWR variation with frequency), which I like. On the other hand, Channel Master claims that the CM422x-HD antennas are "designed for HD", but don't provide any technical data to back up that claim. The CM web page shows contradicting information, stating on one tab that the CM4221-HD is "Designed for UHF/VHF reception from 470 to 700 MHz", and on a different sub-page: "Reception Range = Channels 14 thru 69". Different tabs also show inconsistent physical dimensions for this antenna. Asked for clarification via email more than once, but never received an answer. Called, their support team could not sort out the confusion, but said that the CM422x-HD are being sold for more than 5 years. A fair comparison "on paper" becomes pretty difficult, because confusion dominates when it comes to antenna documentation in general. Some manufacturers do not show any actual data, and market their antennas based on "Range" alone (like selling a car based on "how far it can go on a full tank", while not mentioning fuel mileage, how large the tank is and without saying that the number advertised was obtained driving downhill). There are also antenna makers who only specify "maximum gain", omitting to say that, by design, gain peaks around 800MHz (outside the current US UHF band). Also, the dBi/dBd gap needs to be accounted for, whenever needed. As you said: manufacturers can publish pretty much whatever numbers they want, it is up to us to figure out when those numbers are relevant (and when they are not).[/QUOTE]

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