A Communicator Reprise
September 2015
The counterpoise (sometimes referred to as a ‘Tiger-Tail’) is typically used in antenna systems for radio transmitters where a good earth ground connection cannot be constructed. In this application, it is simply a 19-inch length of common wire attached to the ground of your hand-held transceiver antenna terminal.
In the photo it is attached to a ring terminal with sufficient diameter to fit under the antenna. Alternatively, it can also be stripped of insulation and simply be wrapped around the antenna base, as long as it makes a good electrical contact.
It is very effective in extending the range of a portable transceiver in that it provides the 'missing' half of the dipole antenna for 2m or 70cm operation. In order to keep antennas short and manageable, radio manufacturers coil the antenna wire into a rubber covered spring—half the antenna. The transceiver body is the other half, but is not very effective from an RF perspective. Those little rubber antennas can have a very high SWR, power reflected back to your radio rather than radiating out. The counterpoise, left hanging straight down beside the radio on receive and transmit provides a much more efficient solution.
Try it with a weak station, you’ll surely notice the difference.
~ John VE7TI
Tried this many years ago and I think it added about 0.5 to 1.5 S points. I was using a 19" whip aerial not the original stubby aerial supplied with the rig.
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