![]() Particularly during “receive” due to the tiny capture area of all those severely compromised antenna designs. See below.Īlthough it won’t outperform a somewhat elevated dipole, this will clearly out perform any expensive, short, loaded, lossy “leaky tuned circuit” or transmit loop contraptions. Maybe some kind of LC coupler if your radio needs it. Place another quarter wave wire in the opposite direction on the ground or laying atop more scrub. If you have the space, and can “pull it off”, put out a quarter wave HF wire to the nearest support, even if it’s just laying on top of some 3 foot scrub. Unless you are set up on a 5 square foot balcony under observation, in the Sahara or on the Ross Ice Shelf (no vegetation to support at least one end of a wire), forget those “Buddipoles”, “Isotrons”, “Loops”, “Hamsticks” and other such marketing miracles. ![]() “It’s a brave person who can admit to using a store-bought antenna” Locally customize as required, you won’t need to bring ALL this stuff if you’ve done a little pre-planning. Just simple, effective and proven antennas. It includes pre-made Jungle Antenna ground planes cut for 28 MC and 51.0 MC plus a twin-lead J-Pole vertical for 2 meters. The kit also includes extra wire for dipoles, half-rhombics and Vee beams on other bands. When deployed “low” for NVIS applications dipoles are also known as “cloud warmers”. Known as a “fan dipole” the double-dipoles have been in the Handbooks since the 1930’s it’s the electrical basis for the military AS-2259. This covers both day and night time freqs without having to change anything while camping. ![]() Sun’s down? Freqs down.įor local and regional HF, I usually use a double dipole with legs for both 40 and 80 meters (and sometimes including 60 meters), fed in parallel from the same feedline. (VHF and upper HF.) With an alligator clip to your transmitter it can become a portable quarter wave monopole. Lowest frequency (maximum length) indicated is 17 mc. It then shows where to cut the quarter wavelength wire for that freq. Measure from the dipole center, pull it out stopping at the frequency you are using. Here is a cool 1950’s tape measure for field antenna work. Write this equation inside your helmet: L = 468/f Where L = end-to-end length of the dipole in FEET, f = operating freq in MEGACYCLES. I have used the types of parts and techniques in this kit for 50+ years and it supports almost any kind of field (or home) radio installation from HF through 6 and 2 meters. ![]() Included is my experience-driven rationale for what is in this kit and what is not, and why.ĭescribed below is my kit as it fits in a standard US Military M-1956 “Butt Pack”. No “Rocket Surgery” here, just proven, simple, efficient systems that work very well in a field environment. I’m not into chasing long distance “DX” very much but any of these horizontal wire antennas will work over very long ranges especially when elevated to around a half wavelength.Ī simple kit for temporary, lightweight, deployable wire antennas is essential for any field Ops. My focus is on regional comms with my family, my buddies and EMCOMM groups on the Low HF bands and local comms on VHF. The employment of these antennas is generally for my portable field Ops, typically camping or otherwise vacation/road trips. ![]() The Question: What do you want your portable field antenna to DO? Antennas can have high gain, high bandwidth or small size. ![]()
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