DX QRP On 10 Meter Phone – 5,339 Mile Contact on 5 Watts!on November 3, 2012 at 23:07
Home Brew QRP Portable DX Antenna Project:
There’s a lot to be said for home-brew projects, and this 10 meter portable antenna that I constructed from an old cb antenna and cheap camera tri-pod certainly takes the cake…
The antenna itself was a top-loaded cb/10 meter antenna. I picked it up in a cb shop for around $20 bucks a couple years ago, but after about an hour in the hands of an eager QRP’er, it turned out to be an extremely lightweight, portable, and highly effective antenna that was well worth the time and effort that it took to build.
Eager to test this 10 meter portable vertical antenna, I set it up in my back yard which is only situated at about 210 feet above sea level and surrounded by mountains. So the incoming signals weren’t the best, but immediately contacted Arizona, Isla Mujeres (IOTA off the coast of Cancun,) Puerto Rico, and Cuba. Wow! All from a 4′ whip antenna!
So today I set out to give it an even better test and – man was I surprised… With a pack full of QRP gear, I took a climb up to a local mountain peak near home and got set up in a matter of minutes.
As soon as I turned the rig on, I noticed a huge difference in the signals. I was picking up 10 meter beacons from all over – so many that it was almost too much! And the signal strength was amazing. So, up to the phone area of the band I went to call CQ… And I called for a little while with no response. Tuning back down the dial I heard an Uruguay station calling CQ. I got to him after about 2 tries and nailed the contact. That’s 5,339 miles with the 5 watt Yaesu FT-817nd in USB mode…
That’s pretty impressive with such a small whip size and only 5 watts, but the secret is in the counterpoise. While trying to tune the whip, I was getting higher swr than I liked, so I attached a wire to the grounding bracket and ran it perpendicular to the vertical whip.
After several tuning snips, and one “scrap-it and make a new one,” I finally hit the perfect counterpoise length at 108″. Instantly the antenna was perfectly resonant for most of the 10 meter band with the better swr reading beginning at about 28.400 MHz. Perfect for hitting SSB DX with – No tuner required!
So here’s the run-down on the parts that it took to build this antenna:
1- Top Loaded CB/10 Meter antenna (can be found at any truck-stop along your local interstate) – Mine is the K40 4′ top loaded whip with tuning tip. I found that by removing the adjustable tip from the antenna altogether produced the lowest swr – $20 to $25.00
2- CB Angle Mirror bracket with coax connector – about 9 or 10 bucks.
3- Cheap lightweight camera tripod – I found mine at a local discount shop about 5 years ago for around $8 bucks on close-out.
Trim a piece of wire for your counterpoise to 108″ and solder an
electrical connector to it and attach it to the bracket with a wing-nut and you’re done. A home brew 10 meter antenna that you can use to talk all around the world for less than $40 bucks.
It’s light weight and quicker to set up than a dipole, and you can use the tripod for many other antenna experiments, or use it for your camera!
Hope you get out there with your QRP rig for the next band opening! Please comment below!
73’s Brian KB3ZHX