A little short for a Storm Trooper
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Posted: 7/11/2026 9:43:57 PM EDT
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I built a VHF/UHF jungle antenna the other day and yesterday got to try out it with a new Baofeng UV-25PRO. The radiator and radials are 18 AWG wire. The spreader for the radials is made from 3 pieces of bamboo garden stake cut to 22" each. Each corner is held together with a zip tie, and the end of each radial has an overhand knot and is slipped under the zip tie. At first I cut the radiator too short so I replaced it with a longer piece after measuring SWR with my NanoVNA. After a little tweaking, 1.36 SWR on 146.52 MHz: Attached File 1.06 SWR on 446.10 MHz (I couldn't get the pointer right on 446 MHz): Attached File Pic of it in my Attached File |
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A little short for a Storm Trooper
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I took it out back and hoisted it on a mast made from more bamboo stakes. The tip is about 10 - 11 feet up. Attached File Radio and refreshment: Attached File It worked well to get me into a repeater about 5 miles away. It also received a couple other repeaters over 20 miles away. I also have an Ed Fong J-Pole and receive on this jungle antenna seems a bit better. |
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Jungle antennas seem to be all the rage right now. 6 months ago, everyone would have said to just stick with a roll up j-pole and call it a day. I'm searching, but can't come up with much in terms of when/why you'd use a jungle antenna vs a roll up j pole. Other than the jungle antenna looks like a fun project. Anyone care to give guidance? Cool antenna OP. Good work. |
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Excellent build and writeup  Couple points, last post mentioned poor feedline, you have it. That's why your VSWR curve is so low and bandwidth is so wide. A lower loss (fatter) coax will decrease Antenna VSWR bandwidth, (higher VSWR especially at the band edges), and at the same time make your signal louder. On the other hand, a bit of loss in the coax will protect the final amplifier Transistor in your rig from high VSWR when the antenna falls out of the tree without you noticing .The reason you get different reception on the j-pole is simple. The jungle Antenna has 3 "radials", these are "the other half of the antenna" They prevent of energy from flowing down the outside of the coax. This more or less forces the energy at a right angle to the vertical quarter Wave element (in other words, at the horizon, straight out) The j-pole uses the coax as "the other half of the antenna", since the coax is many wavelengths long, it radiates like any other long wire. This causes the radiation to "split" into multiple "lobes" depending on the length of the coax, and these lobes will not point at the horizon, but up and down , into the sky and dirt. You will probably find that moving the coax on the j-pole changes reception, and moving the coax on the jungle antenna has little effect. Sometimes, depending on just how everything lines up either Antenna will work best in any particular location. Rege P.S. Consider my current location, camping on the side of Big Walker mtn (Va.) A jungle Antenna would send my signal straight into the side of the hill, a j-pole might sent it towards the top of the mtn, which antenna would bounce my wave in the "best" direction would have to be determined experimentally. |
A little short for a Storm Trooper
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FYI, I'm aware that using RG-174 is going to incur more loss than something like RG58, however, this is intended for use as a portable setup and I wanted something light. I was just testing it in my backyard because it was convenient and close to the fridge.  I have a Comet GP-3 strapped to my chimney that's been an awesome antenna for about 20 years.Another reason I wanted to try building a jungle antenna is that I have always had problems stripping the insulation from 300 Ohm twinlead to make a J-pole without damaging the conductors contained therein. I don't have that problem with thicker wire. Which is why I bought an Ed Fong J-pole. |
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A little short for a Storm Trooper
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Originally Posted By d4xycrq: You're 28 miles from me probably a tough putt for simplex. Cool antenna! 73.  It's an Arrow Antennas 2M Yagi. I did ~23 miles simplex with it to a friend running a home built yagi made from PVC pipe and cut up aluminum window blinds. I was using a Yaesu FT-817ND at a blistering 5 watts. We might also be able to do simplex if I use my FT-7800R connected to the Comet GP-3 strapped to my chimney, if you have something equivalent. PM me if you want to set something up. |
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I wouldn't worry too much about the RG174 feedline... at modest lengths at least. 25 foot run is 3.2dB loss on 146 from the Times-Microwave calculator. Which may sound like a lot, but you'd be unlikely to really notice, and the alternative isn't 0 loss. If you did say LMR240UF, you'd cut the loss in half (1.6dB) but that difference is barely detectable on FM even in good conditions. Everything is a tradeoff and everything has points of diminishing returns, including reducing cable loss. |
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3.2 DB of coax loss. What is the VSWR you will see if racoons climb the tree and eat your Antenna, leaving the coax dangling?  You will have no more than a 3:1 VSWR, even with no antenna connected, either leaving the antenna end of the coax open or short circuited. IMHO this is a good idea for field conditions, you trade a barely noticeable reduction in signal strength but gain transmitter protection by never having a VSWR bad enough to break anything even if racoons eat your Antenna  Rege |