Originally Posted by HDTVChallenged /forum/post/12857229
In the real world, it's probably not a big issue. If the antenna works ok now, it's not going to suddenly crap out when chs 53-69 go way.
OTOH, a pure UHF yagi is designed so that the are most sensitive at the highest frequency (Ch69 currently), the sensitivity decreases (sometimes dramatically) as the frequency decreases. Most real world "yagi" designs include a rear reflector that helps offset the loss at lower frequencies. A lower tuning frequency will result in less gain "loss" at ch14 and perhaps a slightly better gain at ch51.
Why tune to the highest frequency you ask? Because the antenna gain rapidly drops to zero dB or less above the tuning frequency.
The most popular and most productive TV antennas are geared toward channels 7-51.
Grant Whipple, TV guru at Winegard Antenna Company, told me, "Focusing an antenna on a narrower bandwidth, in this case 7-51 instead of the old 2-69, creates a better performing antenna with more gain."
Originally Posted by TV Trey /forum/post/16964590
Someone should ask Mr. Whipple why his HD8200U (2-69) has exact same gain figures as the HD7698P (7-69). Could it have something to do with boom length??? Note: Same gain for channels 7-69.
Originally Posted by ProjectSHO89 /forum/post/16964804
Probably because they haven't brought to market any re-scaled antennas.
Since 51-69 have NOT gone away for North America (observe Mexico, Canada, and LP in the US), don't expect manufacturers to eliminate potential markets just because the US' full-power stations have moved to 51 and below.
To do so just to satisfy the opinions of internet posters while sacrificing potential market share wouldn't be very business-savvy.
Originally Posted by Ratman /forum/post/16965274
Other than size... it doesn't buy you much of a "gain" in performance.
"Focusing an antenna on a narrower bandwidth, in this case 7-51 instead of the old 2-69, creates a better performing antenna with more gain."
Originally Posted by ota.dt.man /forum/post/16965335
Currently, AD does not offer a directional 7-51 or 14-51 antenna.