Mike, I and many others use this type of array on the low bands, 80m in
my case. The important features are:
1. The feed lines to each vertical are an odd multiple of 1/4 wavelength
electrical( usually 3/4 wave) and are equal in length. This guarantees
equal currents in the 2 verticals.
2. For broadside operation, the feedlines are connected together and fed
RF.
3. For end fire operation, an extra 1/2 wavelength of coax is inserted
in series with one of the feedlines before they are connected together.
Sometimes the 1/2 wave coax is permanently connected, coiled up, and the
center conductor is shorted end to end with a spst relay to change
directions.
3. The verticals are spaced 1/2 wavelength.
4. The swr will not be 1 and it will change when you switch directions.
It is low enough to be driven with typical linear amps.
There is some information on this type of antenna in the ARRL antenna HB
but there is much more in the Low Band DXing Handbooks by ON4UN.
73, and GL, Dan, N5AR
Mike & Coreen Smith wrote:
>
> Years ago I built a 2m (144MHz)mobile 2 element, broadside/endfire array
> for my car.
> It helped me get into distant repeaters from the College parking lot, so I
> could get into repeaters
> 100 miles away and talk to "home". I estimated 4-5dB of gain, but sometimes
> it really did 'seem' like more.
>
> I've since lost the CQ magazine I got those details from (around 1989 I
> think).
>
> I am thinking of trying something similar again, but this time for the 6m
> band (and for the car).
> Ie: if car was parked facing north, I would want the 2el vertical "array" to
> either beam N-S or E-W.
>
> Does anyone know of a URL they can point me to? (for any band, I can scale
> it)
> Can I use 1/4WL radiators?
> DEtails of phasing lines?
> Spacings?
> etc. etc. yada yada.
>
> Many thanks!
>
> Mike VE9Antenna Antenna
>
> Michael, Coreen & Corey Smith
> (VE9AA, VE9AAA & Baby-VE9)
> 271 Smith Rd
> Waterville, NB
> E2V 3V6
> Canada
> http://members.tripod.com/~ve9aa/index.html
> http://www.geocities.com/RainForest/Vines/2174/
>
> List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
> Trylon Titan towers, coax, hardline and more. Also check out our self
> supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
>
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List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
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supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
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