Using some simple items I made a homemade Yagi antenna great for radio direction finding. The Antenna had a gain of roughly 7.3 dB, an above 50 dB front-to-back ratio, a 3 dB beam width in the E and H-planes (about E= 67.5 degrees and H= 110).
To begin, I first cut some half inch PVC down to 30 inches. The Antenna only required 2 feet, but I left extra on the ends so I could hold have space to hold it, and for making length adjustments as I went along. The 30 inch pipe was then cut in half and joined using 1/2 inch PVC crosses. That made it easier to attach the driven element and Baofeng radio.
After cutting the PVC down to length, I began cutting the elements from a tape measure. The director was 35 1/8 inches long, the driven element was 35 1/2 inches long (the driven element gets split in half making two 17 3/4 inch pieces), and finally the reflector was 41 3/8 inches long.
Once I cut the driven element in half, I sanded the edges to remove the yellow paint. This was to increase the conductivity when soldering the connector for the radio. The director was 12 1/2 inches away from the driven element and the reflector was 8 inches away from the driven element. I used a 5 inch long copper wire and soldered each side to either side of the driven element as seen below.
I zap strapped all the elements to the PVC to secure it in place. I didn’t use PVC crosses for the reflector or director, and this caused an unwanted bend. However, I will fix that the next time I play around with it.
After cutting the excess copper I connected it to the BaoFeng radio to test it. Standing on the roof I pointed the antenna west and received a clear signal from someone 20 kilometers away in Langford. For my second test I pointed the Antenna south and got a response from a repeater 50 km away.
Sajjad Rajput 