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 2m antennas vehicle mounted - multiple antennas query 
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Post 2m antennas vehicle mounted - multiple antennas query
Morning

I was wondering if there was any benefit from having multiple antennas on a vehicle for 2m, with appropriate spacing?
I know very little about phased arrays but I remember seeing several examples where setting antennas up with an appropriate distance between then (1/2 wavelength?) brings benefits.

I am wondering whether having 2, 2m antennas mounted in a vehicle would bring any benefits - possibly only directional?
Just thinking out loud really, but would be interested if this is a thing.

Regards, Mark.
M0NOM

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Mon Nov 25, 2019 8:09 am
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
Certainly looks cool...

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David. G4YVM


Mon Nov 25, 2019 9:03 am
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
Am I to assume you mean verticals here?
In that case you're better off not bothering as directionality isn't what you want.
Sod's law would say the gain would always be in the wrong direction, unless you got very sophisticated.
Just have a longer antenna. :)

For horizontal polarisation, a stacked pair of halos, or clover leaves, would be an advantage.

Cheers

Tony

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Mon Nov 25, 2019 9:48 am
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
OK, yes that is what I suspected thanks for the answers.
Of course if you are a 'prepper' you could justify having two antennas from a redundancy perspective, and I think I've been rumbled - I have some military whips which are really nice and look good, why wouldn't I want two on the roof :)

OK just being silly but presumably a square of four antennas might get you some gain horizontally without the directionality issue?

But I think we should stop there.
Cheers, Mark.

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M0NOM


Mon Nov 25, 2019 10:09 am
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
M0NOM wrote:
I have some military whips which are really nice and look good, why wouldn't I want two on the roof :)


I go to a lot of military vehicle shows & have come to the conclusion that the more whips on the vehicle, the less chance there is of any working radio equipment. If there is a flag on the whip even less chance of a working radio attached to it.

So what looks "cool" or "the business" to the owner can look rather silly to others :)

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Clive

G8ADP in 1964 then G4MBS in 1981 for CW on microwaves esp 10GHz tropo/rain scatter. QRT for 33 years. Moved to GW in 2016 pottering on 6/4/2/70/23 seeing what can be achieved from down in a valley where any QSO is a triumph of optimism over geography!


Mon Nov 25, 2019 10:29 am
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
Co phasing 2 antennae will give a figure 8 radiation pattern... often employed by cb truckers, as this pattern gives gain forwards/rearward... ideal for highway driving.
But for our roads (bendy) a true omnidirectional pattern is preferable... so that's one antenna !

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Paul


Mon Nov 25, 2019 4:13 pm
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
GW4MBS wrote:
So what looks "cool" or "the business" to the owner can look rather silly to others :)


Yes, fair enough. I'll stick to a 2m whip and an ATAS-120A. You'll probably agree coolness level for those hooked up to an FT-857.

Cheers for the answers, Mark.

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Sun Dec 01, 2019 7:05 pm
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
Or maybe two whips only.one of which is actually connected.

I still say coolness is important...tee hee

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Sun Dec 01, 2019 10:27 pm
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
or maybe have more if they do something:

Rear N/S Clark 8m mast (part retracted) 4m-el
Rear O/S Clark 8m mast (retracted) 4m Sirio CX-4-68
Front N/S 2m/70cm whip
Front O/S 6m whip, 4m whip

All connected to something that works & no flags :)

Attachment:
DSC01903 (Large)a (Custom) (3).jpg
DSC01903 (Large)a (Custom) (3).jpg [ 56.17 KiB | Viewed 171 times ]

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Clive

G8ADP in 1964 then G4MBS in 1981 for CW on microwaves esp 10GHz tropo/rain scatter. QRT for 33 years. Moved to GW in 2016 pottering on 6/4/2/70/23 seeing what can be achieved from down in a valley where any QSO is a triumph of optimism over geography!


Sun Dec 01, 2019 11:28 pm
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 2m antennas vehicle mounted - multiple antennas query 
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Post Re: 2m antennas vehicle mounted - multiple antennas query
Nice clive.

I've often pondered fixing a mast to my LWB Defender but never got round to it

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David. G4YVM


Mon Dec 02, 2019 7:40 am
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Post Re: 2m antennas vehicle mounted - multiple antennas query
I have a mate who's a SGT in the royal signals and you know what's weirdly funny he doesn't know anything about RF coms all he does is internet coms.
He once asked what do you do with those radios and I replied well you did Morse in the signal's give up..... he said no what I do is all IT :shock: We have other guys that do all that aerial business, how times change and the land rover pic kinda rekindled that story.

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Mon Dec 02, 2019 11:03 am
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