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Antenna R&D
Excellent link with antenna comparisons with spectrum analyzer
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<p>[QUOTE="EscapeVelocity, post: 45423, member: 3771"]Or rather, a 1/4 wave dipole, with 1/8" segments left and right. See how I referenced the 1/8th wave FM antennas, commonly available over the years as indoor FM antennas. They arent great antennas on FM but if you ganged 4 or 8 together and then reinforced them with a 1/2 wave reflector element...then you will see a decent gain. </p><p></p><p>The DB8 has a less effecient reflector at 20" x 12 (4 altogether) The CMs have the 1"x2" mesh screen at 30x39 and solid rods at similar lengths on the new Chinese version. It's resonant at VHF High frequencies, much more so than a 20" screen. The Winegard similarly uses 2 HD 4400 screens instead of continuous single screen. Thus losing that bit of increased resonance help.</p><p></p><p>The DB8s 6.75" whisker length is also a bit smallish, for 1/8 wave at VHF High. But the bowtie design is a broadbanding technique itself.[/QUOTE]</p><p></p>
[QUOTE="EscapeVelocity, post: 45423, member: 3771"]Or rather, a 1/4 wave dipole, with 1/8" segments left and right. See how I referenced the 1/8th wave FM antennas, commonly available over the years as indoor FM antennas. They arent great antennas on FM but if you ganged 4 or 8 together and then reinforced them with a 1/2 wave reflector element...then you will see a decent gain. The DB8 has a less effecient reflector at 20" x 12 (4 altogether) The CMs have the 1"x2" mesh screen at 30x39 and solid rods at similar lengths on the new Chinese version. It's resonant at VHF High frequencies, much more so than a 20" screen. The Winegard similarly uses 2 HD 4400 screens instead of continuous single screen. Thus losing that bit of increased resonance help. The DB8s 6.75" whisker length is also a bit smallish, for 1/8 wave at VHF High. But the bowtie design is a broadbanding technique itself.[/QUOTE]
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Antenna R&D
Excellent link with antenna comparisons with spectrum analyzer
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