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?
Anytime I see a gain of around 6 db at a frequency around 150 mhz the
antenna beter be about 20 feet tall.  If not it could be refferanced to a
dummy load or most anything else.  An antenna around 36 inches long is
usually rated about 3 db of gain at 150 mhz.  That is not even refferanced
to a dipole.  About 18 inches of antenna is a 1/4 wave whip.  It is minus a
db or so refferanced to a dipole.
You might get an antenna modeling program to show the 6 db of gain if it is
isotropic and also you add some ground reflection in.  This is not usually
done on vhf.
I would not even fool with the manufacturer that makes a claim like this.