On 10 Jan 2004 21:29:12 -0800, (SDNomad) wrote:

I am trying to find out if the performance claims on the GAM SS-2
antenna could be accurate. http://www.gamelectronicsinc.com/mini.html
I found 2 reviews that rated this antenna #1 for a vhf short marine
antenna.
One was by Powerboat Reports
http://www.powerboat-reports.com/pub...es/4722-1.html .
And the other was by Practical Sailor
http://www.gamelectronicsinc.com/practical.html

I spoke with the manufacturer and he said the gain on this antenna is
6db or 5.1dbi. Is this possible or not possible from a 35" whip base
load antenna? If it could be possible, then under what conditions
would it be possible to get that type of gain from an antenna this
size?

I plan on calling the manufacturer back. What would be some good
questions to ask to find out the true performance of this antenna?

Thanks,
Doug

Doug,
Their 6db claim is in reference to a "coaxial antenna" and not against
a dipole; which would read dbd, or against an isotropic source which
is the dbi rating. Basically it's a marketing ploy. What they have
is essentially an end-fed half wave antenna which should perform
fairly much like a 'reference' dipole. You might want to ask them to
describe their "coaxial antenna" and what it's performance is in
comparison to a dipole and isotropic source (you should find about 2.1
db difference between the two - if not you are being hit with
'marketing science'). Gain in an antenna is a relative not an
absolute measurement, if they compare it to a wet string I'm sure the
gain would be enormous - it's all in how you represent a product.

I looked at the site and what I saw is your basic end fed half-wave
antenna - the lack of need for radials is what clued me in. The gain
should be about the same as any other antenna of same/similar design.
That being said, if they are rated as being more durable than other
manufacturers that is a plus -especially in the marine environment -
but don't expect more gain.

Good luck, but I am skeptical that you will get the 'true' performance
of this antenna from the manufacturer.

Howard