VE3LNY's AVR Projects

VE3LNY's Antennas

3 Band HF Vertical for 10, 15 and 20

I live in a bungalow with a very gently sloping roof. This is ideal as a platform for antennas, because it is easy to access and safe to work on. Using two old aluminum poles a total of 1/4 wavelengrth at 20 meters in length, I built a 3 band vertical for 10, 15 and 20 meters. The pole is approximately 5.3 meters or 17' 5" long. It is insulated at the base with a plastic pipe fitting, and supported by 3 guy ropes at the junction of the two poles, so the eye hooks also keep the two pole segments fastened together. (The crossing wires in the photo are either from my dipoles or the hydro line at the street.)

There are two thin plastic pipe cross members, one at the bottom and the other about 2/3 of the way to the top. They are held to the mast with stainless steel hose clamps. The 10 and 15 meter radiator wires are at either end of these struts.

The 3 radiators are connected together at the base of the pole. The plastic tube contains a 2:1 UNUN which greatly improves the match to the 50 ohm coax. Around the base are a number of radial wires, soldered to a copper ring and the coax shield. The radials are 1/4 wave at 10, 15 and 20 meters.

Each radiator has been trimmed in length for the best SWR in the center of its band. The SWR is low enough so that no antenna tuner is required. I have made many contacts with this antenna and I like it very much.

G5RV Dipole

The tower is a 40 foot TV tower, supported by the chimny of my house, and attached with slotted angle brackets at two levels. At the top of the tower I placed a 5 foot (or so) copper pipe horizontally, attached with stainless steel hose clamps. My two dipoles attach to either end of this copper pole. The G5RV can be seen at the left of the 2nd photo.

The G5RV is a standard issue puchased at a fleamarket. Each leg goes to a tree in my front and back yards, so the elements are essentially horizontal, with considerable sag to allow for tree movement. The antenna has survived 18 winters so far. Thanks to my good friend VE9SNB for his archery skills (not much luck training the squirrels around here).

The twinlead drops down the tower using standoffs made from plastic coat hangers. It is a few feet too long, so I loop it around and back up the tower a few feet. Then I connect 50 ohm coax directly to the twinlead. I use several ferrite beads as a current choke at the end of the coax.

This antenna has exceeded expectations for me. It can be used on 40, 20 and 17 meters without a tuner! With a tuner it can be used on any other HF band, with the exception of 160 meters.

2 Band trapped vertical for 17 and 30

The other dipole antenna on my tower is a 2-band trapped dipole for 17 and 30 meters. (See the photos above for my G5RV. The traps are visible in both photos.) There have been many articles written about coaxial traps, but the one that caught my attention was Optimizing Coaxial-Cable Traps by R.C. Sommer N4UU, in December 1984 QST. I liked the idea of using traps, but weatherproofing a coil/capacitor unit was beyond my ability. Coaxial cable traps, on the other hand, are so much simpler. I put this antenna together with one pair of traps resonant at 18 mHz and with a little pruning, had the antenna resonant on both bands.

The antenna has been up for many years with no apparent deterioration. The only weatherproofing I used was to put a blob of "coax-seal" on each end of the coax in each trap.

2 Meter J-Pole

When my 25 year old ringo ranger finally corroded into uselessness, I decided to replace it with a home brew J-pole. Plans for this kind of antenna can be found everywhere on the internet. You just cut a few copper pipes, solder together with some fittings, attach a feed point and its done. If nothing else, I learned how to solder copper pipe in my life.

The J-pole is mounted at the top of a ten foot fence pipe, mounted on the hydro entrance pole on my roof. (Yes it is clear of the hydro wires, spaced two feet away with slotted angle brackets.) You can see the coax feeder, looped into a few turns for safety. This antenna works just as well as the ringo did, and cost very little to make.

6 and 2 Meter Yagis

As I said on my home page, I really like operating VHF DX. I cannot mount an HF beam on my modest tower, so VHF antennas fill the bill.

At the top of the tower I have a simple TV rotator and a short mast. Just above is a 3 element 6 meter yagi. At the top of the mast is a 6 element 2 meter yagi. Both were purchased at local fleamarkets. Both use gamma matches.

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