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poor mans gainmaster

bob85

Supporting Member
Mar 30, 2005
3,480
1,461
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england
me and a local decided to build a gainmaster from parts we have laying around the shack, if it works as intended we will build a higher power version.
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The Gainmaster is a $179 vertically polarized, balanced, center fed, wide bandwidth, 5/8 antenna made from coax and wire, housed within a telescoping fiberglass radome, with about 66% more 'in-phase' active element area than a normal bottom fed 3-4 radial metal 5/8, and which provides about 1-2db more gain on the horizon than the $150 Super Penetrator 500 or the $359 I10k.

Go here and click on the links on top in the orange area to read all about it. I love mine!

My Penetrator 500 is now a pile of disassembled aluminum tubing and parts stored in the garage as a back up antenna.
 
nice project bob , be sure to post plenty of pics for us (y)
what are you gonna use for the support tubing ? i recall reading somewhere that the velocity factor of that tubing effects the antenna inside quite a bit .
 
needlebender
the red stuff is the wire for the upper half, we will try different coax and see how it goes,

booty
we will be using fiberglass fishing poles as support, the dielectric properties of the radome will effect the antenna to some extent,
its just an experiment using things laying around.
 
needlebender
the red stuff is the wire for the upper half, we will try different coax and see how it goes,

booty
we will be using fiberglass fishing poles as support, the dielectric properties of the radome will effect the antenna to some extent,
its just an experiment using things laying around.

Any idea of the impedance or capacitance per foot of the factory Gainmaster Red coax?
Your red coax isn't the same?
 
we don't know what the red coax is, its 5mm same as rg58, you have standing waves on the section of coax above the stub, 500w into rg58 with high vswr is pushing it hard.
 
Hey Bob, quite the enterprising idea there.

Over here I would think the base element alone, 1 - 3/4" x 75" fg fishing pole, would cost quite a bit, and you'll still need three more smaller sizes too. Why not consider to hang the prototype between two trees and work out the kinks, unless you think adding back the support material will be a big contributing factor for the tuning. Here is a link that might be helpful: Installing Wire Antennas

Whatever happened to your project to build a New Top One out of a Vector? I saw a picture of one you made that looked very similar. A neighbor of yours from Ireland just posted about his success with his New Top One.

Keep us posted.
 

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