Friday, September 21, 2007

2 Meter VHF HT Handheld Ground Plane, Tiger Tail, Lambda Wire Antenna

I have been an Amateur Radio or "HAM" radio operator for over 2o years. My call sign is KB7BXP. I was about 10 or 11 when I first got into the hobby. However, I haven't been active in the hobby for the last 12-15 years until the last couple months. I needed something to do while making a long 1 1/2-hr commute. Amateur radio has been the perfect answer to keep me awake on the long drive home after a 12-hour shift.

The first radio I purchased was the Yaesu VX-170 2-Meter Handheld or HT. This is a great little radio. However it comes with the traditional "Rubber Duck" antenna that has only marginal performance. I also purchased a 5/8 Mag-mount external antenna to use while I drive. But I wanted to extend the performance of my HT while using the radio around the house or when walking around town or the neighborhood.

That's when I read about a simple little antenna modification that greatly increases the receive and transmit capability of any handheld radio. This antenna modification is referred to as a "Tiger tail," "Rat Tail," Lambda wire, ground plane, or counterpoise antenna. This modification simply comprises a 1/4 wave length of wire attached to the body or base of the antenna in some fashion. After a quick trip to the Walmart Automotive section and 10 minutes of cutting and crimping, the project was complete and the results speak for themselves. The following pictures describe the project.

Needed Supplies:

Wire Cutting, Stripping, and Crimping Tool.
Spool 12-gauge automotive electrical wire.
Package automotive electrical ring connectors.

Making the Antenna:
Cut one or odd number of 1/4-wave lengths of wire.
Strip 1/4 cm of outer plastic sheath from one end.
Place stripped end into ring connector and crimp yellow plastic section X 2.

2-Meter 1/4-wave at 146 MHz = 20 1/4 in. But anything close such as 19 1/4 or more will work.

Connecting Antenna:

Attach ground plane wires to base of SMA connector or from belt clip screw on back of radio chassis or battery case.

Any kind of wire can do. I have also used twin-lead speaker wire and attached 3 1/4-wave wires to one ring connector.


Justin said...

I have a VX7 and built your version of the tiger tail today -- I'll give it a shot and see how it works!

Anonymous said...

Hallo,can you post please a picture with the whole wire?