Vertical Antenna Tilting
Why is the vertical angle of my antenna important to reception?
- The best antennas I have found for difficult reception locations are
directional Yagi's. Directional Yagi's have both a narrow horizontal and
vertical beamwidth, this focuses the antenna directly on the source thereby
blocking out reflected signals.
- Most people realize how important it is to use a horizontal rotator to
fine-tune the position of their antenna by pointing it towards the
transmitters, but few realize how important the vertical angle can be. The
weaker the signal, the more important precise positioning becomes.
- There will always be a optimum vertical angle for the antenna in which the
signal is strongest. This angle may vary from one station to another. A
remotely adjustable tilt angle will allow you to find the sweet spot when
trying to tune in those difficult stations.
- Vertical angles can also vary if you aim your antenna towards different
transmitters that are far apart from each other. The angle that works well for
one transmitter may not work as well for the others.
- Strong signals do not require such precise adjustments, it is mainly for
those channels that have a very weak signal, or drop in and out often.
- Sometimes pointing your antenna upwards directs its reception away from
stray signals that are bouncing off the ground.
- A fixed tilt angle can be used in good signal conditions. In this case,
you want to optimize the angle for your weakest stations..
- Both horizontal and vertical stacking can decrease the beamwidth quite a
bit. This makes positioning the antennas very important in locking-in the
weakest stations. Sometimes just changing the angle just one or two degrees in
any direction can cause a signal to drop out completely. I have found fine
tuning for the strongest signal is just a matter of plus or minus a half
degree.
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