The main disadvantage of a 4 bay omni is lthat you will pick up any QRN
located anywhere. But a 4 bay absolutely has gain on the horizon. A 4
bay would have the proverbial 6 Db of gain, minus splitter/feedline and
connector losses. What the 4 bay does is squash the donut flatter, and
out. My day job depends on this (radio broadcast engineer with 5 FM
transmitter sites).
I plan to put up a 4 bay omni for six at my remote base site. Then
I switch over to the very quiet Innovative beam.
We all should look at more of these antennas, but, to obtain the full 3
Db gain per doubling, you need to space the bays a full wave length,
which is 20 feet. So the 4 bay would be 60 feet, bay 1 to bay 4. You can
get by with half-wave spacing, with less gain.
Tom Bosscher K8TB
On 9/17/2013 9:47 PM, John Geiger wrote:
If you stack 4 of those elements, and it is omnidirectional, then the
gain has to come from somewhere. Where does it come from? It would
probably compress the take off angle, but in terms of beamwidth gain
relative to a Yagi, it couldn't have any.
It wouldn't allow you to null out noise coming from a specific
direction, which can be useful also.
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