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Latest Posts

Topic Author Posted On
Dipole Question KD5IUS 5 days, 12 hours ago

That is likely to draw too much attention.

At present, the best way of dealing with antenna restrictions is to display the American Flag on a metal flagpole and use the flagpole as an antenna. George Bush signed into law the Freedom to Display the American Flag Act of 2006--this law takes precedence over covenants and HOAs.

Zack Lau W1VT
ARRL Senior Lab Engineer
dBmicrowatts? KO0Y 6 days, 5 hours ago
To convert dBuV to dBm subtract 107 dB: dBm = dBuV - 107 dB
two db-224A's on a repeater tower question N0MZR 1 week, 2 days ago

No, you can't get a higher gain antenna and still have a nice omni pattern by doing that. If you orient them so that you get an omni pattern, the gain goes back down to where you started. If you orient them for more gain in one direction, you no longer have an omni pattern. No way to get both, assuming that the net height, from the lowest antenna, to the top one, remains the same.

The only practical way of getting more omni gain is to stack the two vertically, doubling the net height of the antenna. This gives you more gain at the horizon, at the expense of a compressed vertical pattern. Usually this isn't a problem.

That arrangement may allow two different repeaters, run by different owners, on the same tower.

Zack Lau W1VT
ARRL Senior Lab Engineer.
SWR WA6ZFM 1 week, 5 days ago

Even if the wire is insulated, you can still get significant capacitive coupling to live foliage. The effect is more pronounced at the high impedance ends of the antenna.

With a 40M dipole, I was able to reduce my mid-band SWR from 1.5 to 1.2 by cutting off a maple tree branch that was up against the end of the dipole.

Zack W1VT
ARRL Senior Lab Engineer
Digital QST crashes constantly on iPad3 K9AO 1 week, 5 days ago
Recent news report about this issue.

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