this is for 903 and 1296.. "half the boom length" is not a very good
idea with bands where the wave length is normally measured in
centimeters .. also he could have a 5 element with a 12" boom.. or a 55
element with a 180" boom.. big difference..
according to directive systems.....
Loop yagis can be stacked like any other antenna for increased gain.
An increase of approximately 2.5 dB or greater, can be realized each
time the array size is doubled. Antennas can be stacked vertically or
horizontally, although we recommend stacking two antennas horizontally
when space permits. Although this makes the horizontal pattern sharper,
it makes the pattern cleaner in the vertical plane with a resulting
improvement in signal to noise ratio.
k_berglund@waymark.net wrote:
> My real simple answer is…
> If you are stacking only two identical vhf yagis, stack them one above the
> other.
> This decreases the beamwidth in elevation, but hardly changes the azimuth
> pattern.
> You get the increase in gain but don’t have to point the rotor any more
> accurately.
>
> The distance you stack the yagis is a function of their gain. A general
> rule of thumb is half their boom length, but consult your manufacturer for
> a more accurate figure.
>
> Make sure that you consider phase, and impedance matching in your setup.
>
> Keith WB5ZDP
>
>
>
>> I want to stack two 903 and two 1296 loop antennas. What is the best
>> arrangement? Is it best to
>> stack like antennas vertically one above the other or horizontally one
>> beside the other and why?
>>
>> Thanks for your insights.
>>
>> Dennis N4DD
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>
>
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