I've had decent luck with simple counterpoises.  They are almost like making a dipole, in that the wire is about the nominal quarter wavelength.  Usually on the rig itself, attached to its ground lug, used with a long wire for an antenna.  [Although if I have an unbalanced antenna (like a vertical, or an inverted L) I have used them to keep RF off the transmitter, if I don't have a good earth connection.]

I'd think for the ham bands a counterpoise for 80m and 40m would work well (20m and 10m of wire, give or take), and might work well enough for all bands.  Length isn't critical, just run wires away from each other.  And they can be used inconjunction with any other grounding (earthing) scheme.

Shawn Upton, KB1CKT
Test Engineer
Allegro MicroSystems, Inc
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603.626.2429/fax: 603.641.5336

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Brian Ellis
Sent: Tuesday, March 01, 2011 12:30 AM
To: [log in to unmask]
Subject: Re: [TN] NTC: GEC BRT 400S

Absolutely, Shawn, I'm 100% with you. Simplest is best and cheapest. 
Have a reasonably long wire antenna of indeterminate length but with a 
good earth (not ground) and you won't go wrong. You may be a few dB 
lower than a dipole, depending on the orientation of the directional 
dipole. Now for the good earth: you should dig a hole, say 1 x 1 x 1 m 
in your garden, away from the eaves of the house. Buy a copper sheet, 
say, 75 x 75 cm and 3-5 mm thick. Fix to one corner some 19-20 mm wide 
copper braiding with a M8 brass nut and bolt, clamping well between 
copper washers. You can even solder the braiding to the sheet, as well, 
if you have enough horse power to take that lot up to ~200°C. Protect 
the connection against corrosion with a good varnish (electrical 
characteristics are not important). Lay the sheet in your hole and 
refill with soil. Traditionally, you then piss on it. Run the copper 
braiding BY THE SHORTEST POSSIBLE PATH up to the earth connection on 
your Rx. Do not use power ground as an earth. An alternative to the 
copper plate is an earth spike; this is a 2-3 m long copper (alloy?) 
spike, about 30 mm diam but with a star profile (max surface area) that 
you simply hammer in. Easier, but the sheet is better.

Such a system will give you excellent results at all frequencies, 
especially if one end of your long wire is a few m higher or lower than 
t'other end..

Remember dipoles have a cardioid directionality and you will get zero 
reception along the axis of the wire, yes, zero.

Brian


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