tempory base antennas/groundplane size?

Joined: 24 Jun 2008 Posts: 1

I occasionally have to set up UHF base stations in tempory locations to give extra range to our comms network, normally I use a magmount UHF panaroma mobile giving 2db gain and stick it to a household object such as a microwave, fridge , radiator or cookerhood. These seem to work ok if I have these luxuries, its if we have a tented camp or other relatively metal free environment, but I was wondering if I would get better performance from a dual band ham antenna (I've seen them quoted at 5.5bd gain) on a home made ground plane. I was thinking a flat plate with so239 base and 3 or 4 radials coming out
How big would the groundplane have to be in terms of legs?
is my plan fatally floored or is my theory sound, or is there an easy alternative I've missed.
If we're abroad some places we can run 35 or 50 watts so it has to have that sort of power rating.
thanks in advance
John

Posted: Fri Jun 27, 2008 1:23 pm

Sorry this forum isn't very well at the moment, I'd recommend the forum at http://www.transmission1.co.uk/ for the time being!