[VHFcontesting] Gain of 4 stacked 5/8 wave

[Ev Tupis]

--- On Thu, 8/7/08, John AA5JG <aa5jg at lcisp.com> wrote:
> "Gives you four times the gain of a single 5/8 wave.
> Includes 2 MFJ-1764 5/8 Wave antennas, phasing cables.
> Doubles gain on 6 Meters"
> 
> The stacking distance between the 2 dipole feedpoints is 12
> feet.  Now, what kind of gain could one expect on 2 meters
> with this mounted horizontally?  I am guessing that 6 meter
> gain should be 3Dbd or so.
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The "simple answer" is embedded in in your e-mail. :)

"Doubles on 6 meters" = 3dB, as you guessed.
"Gives you four times the gain of a single 5/8 wave." = 6 db on 2 meters.

There are assumptions at play:
(1) On 6-meters, the gain is relative to a dipole.
(2) On 2-meters, the gain is relative to a 5/8 wave monopole (as stated)
(2a)Stacking a second 5/8 at the end of the first 5/8 will yield 3dB
(2b)Stacking a second 5/8 x 5/8 at 12 feet will yield another 3dB

I have used these antennas successfully, btw.  However, please know that they are *not* to be considered rugged (but can be "ruggedized").

Regards,
Ev, W2EV