In article , Ian Jackson
wrote:
In message , UnsteadyKen
writes

tony sayer wrote...

Think how much better it would be with a decent Vertical dipole;-)..

Who knows why they use these halos?,

1. Halos are compact and very easy to mount on (around) a vertical mast.
They don't clutter up the space required for other aerials too much.

2. Halos have a well-defined, pretty well omnidirectional gain of around
minus 3dBd. The fact that that there a minus sign there doesn't
necessarily indicate that it doesn't perform adequately.

Depends on how you define 'adequately'. ;-

Yes, the user may still get enough signal to keep them happy. Although for
VHF - as people have said - a vertical dipole will probably provide more
gain.

Another way to look at the halo is to wonder where the power goes if you
try to use one as a TX antenna. This may give a clue to the inefficiency
when used for the task for which they are fitted.

I'd have on my list of reasons for why they are used:

N) Because they look to the punter like they are getting something more
impressive than a 'bit of wire' (i.e. a dipole). So the installer can
charge more for them.

and also sometimes:

N+1) So the installer doesn't have to spend any time aligning them toward a
local TX. Fit, down the ladder, present the invoice.

Slainte,

Jim

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