The DBJ-1 Dual Band J-Pole Antenna

This is a very limited test and review of the DJB-1 dual band HAM antenna that I purchased from Dr. Ed Fong (WB6IQN) on eBay. I recommend buying directly from his eBay store since the proceeds goes towards his students. They often make the antennas as an exercise under his supervision. Mine was well-made and performs nicely.

After installing the antenna in the peak of my attic away from all electrical wires and air conditioning, I connected about 50 feet of LMR-400 to it. I then connected my Chinese antenna analyzer and tested both 2m and 70cm bands. Everything looked good and I was just in time to check in to the SE Linked Repeater Net and give it a whirl with my Baofeng UV-5R V2+ HT.

The day after, I set out to see which 2m repeaters I could hit on low power (1 watt), and get some signal reports. The first try was 23 miles away with great reports. The second attempt was 32 miles away with great reports. The third try was 42 miles away and I was able to hit that repeater with 1 watt and full quieting. Pretty good! There were some repeaters I could not hit that were a bit closer, but I cannot verify if they are up and running.  I’m located at one of the highest points in my town, and I think this is what is helping the DBJ-1 perform so well for me.  They are a relatively horizontal pattern antenna and mine is located at a decent elevation with respect to my surroundings (and area repeaters).  I’ll try for more distance on both low and high transmit power when I have more time.  I will also plot not only distance, but direction and elevation differences between my station and repeaters. From there, I will rotate the antenna and see how this affects performance to fringe repeaters.

Below are a series of images showing the test result using my Chinese made KVE 520A analyzer. This small box shows 1:1 SWR with two different 50Ω terminators. Good enough for me since I compare antennas instead of relying on accurate numbers for each antenna. I would love to someday find out how well this little box is calibrated.

Please excuse the crappy smart phone pics.

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