Product Review
TBJ-1
Tri Band Base Station Vertical
VHF UHF & 220 MHz
2.1 dBi gain (all 3 bands)
Featured in: QST March 2017
Review by: John 'Miklor'
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The creator of the infamous DBJ-1 and DBJ-2, Dr. Ed Fong, has done it again with his recently patented TBJ-1. A true Tri-Band vertical with No Radials. Assembly & Tuning The TBJ-1 is shipped fully assembled and ready to install. Two U-Clamps at the base and it was ready to go. The 6' antenna is encased in 3/4" Class 200 PVC. The antenna is not a generic 'one fits all' antenna, but is specifically pre-tuned to the amateur bands. 144-148 MHz, 220-224 MHz and 440-450 MHz and rated at 75W. Customization You have your choice of connector when ordering. The SO-239 is standard, but if a Type N connector is desired, it can be substituted at no extra charge.
Design The design is different than any other antenna I've owned, but rather that try to explain it, I've attached a copy of the description submitted for the patent. Ed explains it much better than I ever could. Link to Patent 9,608,336. Performance I wasted no time getting this up in the air, as in Pennsylvania we only have a two week window between summer and winter. Here is where the Rubber meets the Road. The specifications state a 1.3 to 1 SWR on all bands. When tested here, the antenna held true to its specifications.
My first test was naturally on 220 MHz. Out here in the sticks, I have three 220 repeaters within range, the closest of which is 35 miles away. I had absolutely no issues getting a solid signal into and from all three repeaters. As for the VHF and UHF bands, the performance was identical to the DBJ-1 that it replaced. Use Good Cable Here's where you don't want to short change yourself. Everything you gain by running a good antenna goes right out the door if you use inferior cable. Here is a link to a Cable_Chart that can be used as reference. Installation The antenna should be supported only by the lower 10 inches of the housing to avoid interaction between the matching stub and any nearby metal, such as an antenna or tower. The antenna is light enough that hose clamps can be used for mounting. Tree Mounting If you're lucky enough to have trees on your property you may want to consider this add on. Carefully drill a small hole and insert a small eye bolt through the plastic cap with a nut on both sides. Make sure the bolt doesn't extend far into the antenna area where it could interfere with the antenna. Secure the bolt with Loctite to keep the bolt secure. A rope can now hoist the antenna into place for that backyard or Field Day installation.
Because the antenna will be supported from the top rather than the base, it will be necessary to cement the end caps in place, rather than hand tightening. So where do I get one? You can get a DBJ1 from Ed directly. Model descriptions and pricing link can be found below. He can be contacted directly at: edsantennas@gmail.com 1163 Quince Ave., Sunnyvale, CA 94087 408-245-8210 Conclusion The antenna is lightweight, efficient, and very affordable for someone on a tight budget. I can give this antenna nothing less than a top rating.
From Ed's Desk More info about the antenna from the developer, Ed Fong WB6IQN
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