Antenna Systems

Posted: 09/21/2015 in Communications

I am going to attempt to answer several readers comms questions over the next few weeks by giving an explanation of my current HF setup for local to mid distance comms.

I use a digital software, RMS Express (part of the WINMOR package) in conjunction with a certain antenna system, HF transceiver, 12 volt power supply, a PC, tuner and a modem. This setup allows for reliable HF communications from 0 out to about 300 miles, across the wildly varied terrain of the Southern Appalachian mountains and adjoining foothills. This system will pretty much give me coverage in all of the valleys and ridges in my area. Try that with a VHF/UHF system even if you have repeaters. My current setup requires no external infrastructure outside of a 12 volt car battery and a way to keep it charged. I can use my car charging system, home solar system or a man-portable solar system depending on which rig I use; my base station or my tiny man-portable system.

First, you have to have your General or higher Amateur Radio License to access the frequencies you will need to make this work. If you are thinking that you and your buddies will put this system together after SHTF and start talking, then you are delusional. The group I routinely make comms with all hold General and Extra Amateur licenses and it still took about 3 months for us to work the bugs out. If you think that you can pirate the frequencies to test and maintain your system you are even more delusional. The “Ham Nazis” will catch you and turn you over to the FCC. They will look up your bogus call sign on the internet and DF your location just for sport (look up “foxhound”). And rightly so. They took the time and expense to study and pass the test. It’s not that hard. Now that we have again beaten the proverbial dead horse regarding licenses (much like Mosby and PT) lets get on to the equipment.

The antenna I currently use, and have a lot of success with is the Buckmaster 300 watt, 7 band OCF antenna.

http://hamcall.net/7bandocf.html#7band

I chose this antenna for several reasons.

Being a offset center fed (OCF) antenna (45′ on one side, 90 on the other, total of 135′) allowed me to physically locate the feed point of the antenna closer to my radio room with a shorter lead in RG-8 coax, about 30′ long. I had less room to fit the antenna along one side of the building than the other.

The antenna is resonant on nearly every band I use, it always tunes up quickly, doesn’t require a tuner (I still use one) and, if properly installed, has very little VSWR. Some radio guy will me write to say “My such-and-such antenna works better and costs less. Great, send the info. on it. The Buckmaster has worked great for me for years now. Dodge, Chevy, Ford, whatever…..

If you are interested in working down in the 160 meter band (which I am for reasons I won’t go into here) then go for the Buckmaster 8 band antenna. Just remember you will need approximately 270′ of space, or nearly a football field. And, you will most likely need a tuner for 160 meters.

On their website, Buckmaster shows the antenna slung up higher at the mid-point than at the ends. That is correct if you intend to make HF comms like most Ham operators, as long-haul as possible. I, however, want to make comms that will fill in the area between the ground wave and the sky wave. The dreaded “Skip Zone”. If I want to make long-haul comms, I will raise the center rope.

Here is a link that describes the skip zone:   https://en.wikipedia.org/wiki/Skip_zone     Pay particular interest in the words “vertical incident”.

Since most of the folks I want to talk to are in my region (Meat Space Folks) I need a technique that overcomes the skip zone. That technique is Near Vertical Incident Skywave or NVIS.  Yet another link if you have the time:

https://en.wikipedia.org/wiki/Near_vertical_incidence_skywave

Bottom line for me and most of the folks I talk with: we have our antennas generally about 12′ off of the ground for the entire length of the antenna. Once you are on the air, you can adjust it up or down and see what happens.

Some folks will say it is a more efficient use of RF power to build an antenna for the center freq you are using in each band and use a tuner. That is true, however, if you work off of a Signal Operating Instruction (SOI) that says to change your frequency twice a day, every day (60 total for each band per month), then the multi-freq antenna becomes more desirable.

My antenna is attached to trees using Dacron UV resistant ropes that I found at The Wireman. His link:  http://www.thewireman.com/   I attached marine pulleys (also bought at Wireman), to trees at the 2 ends and center points, attached the rope to the end insulators and center balun connector, connect one end of the RG-8 coax to the balun and hosted away. Then I tied the free running ends of the ropes to fence staples at the base of the trees. You can attach strain relief to the ends of the coax for extra security.

In good SF comms tradition, I drilled a hole into the exterior wall of my radio room and fed the coax though it. I still have not foamed the hole shut. I have a friend who would be mortified if he saw my radio room. His looks like the helm of the Star Ship Enterprise. Too each his own, mine is functional, and can be torn down quickly and thrown into a couple of Pelican cases.

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Comments
  1. Doug says:

    Man that sounds like the perfect rig for these ridges and hollows. My AO north of you along the edge of the western spine of the Manogahela’s, at 3000 ft. 1000-1500ft elevation changes in a mile to 2 miles are the norm, and that is by the paved one lane goat paths that pass for roads. Hoofing it by nap of the earth those elevation changes go up by another 500 feet or more.

    The more I learn the more it seems antenna’s are everything.

    Excuse my ignorance, (I’m just trying to understand all this awesome comms stuff in order to make informed decisions as to the most practical set up and funds available), would you recommend this style of antenna for the skip zone in my AO terrain using VHF/UHF. I have to crawl before I can walk, and the HF stuff your talking about is beyond my understanding right now. An antenna that does double duty would be highly advantageous as upgrades in equipment become feasible.

  2. Alfred E. Neuman says:

    Reblogged this on The Dixie Traveler.

  3. Wrench says:

    You can never learn enough about antenna’s and the best part is lesrning from others. Thanks Dan!

  4. Excellent article and glad to see all the good people working NVIS. One item I notice you did not mention is feedline. That’s an essential part of an antenna system and can impact this quite a bit. Use quality feedline (e.g. LMR-240, LMR-400, Beldin 9913F7, etc.) and solder the connectors. Don’t expect crimp ons to last in weather due to galvanic corrosion. Thanks for the great info.

    • Freebird says:

      Excellent advice thank you very much! I already have my general ticket acquired roughly six months ago. Strongly considering Yaesu 857d as primary for field and mobile all band all mode communications. Will definitely look into the antenna references thank you very much. Greatly appreciate it. 73

    • Freebird says:

      Great point! Should HF feedline be ladder type or can it be coax?

      • My station is setup with coax brought into the shack. I terminate my ladder line into baluns (4:1 for my loop, 1:1 for my G5RV), then run coax into my shack. Better coax reduces losses on antennas you need to tune and also has better shielding so there is less RF interference from local stuff (e.g. computers). Finally ladderline is essentially lossless, if you can run all ladderline, that also mitigates losses.

  5. nick says:

    Doug, NVIS doesn’t work for VHF/UHF. You really need to get your General class and get into HF. The test itself is not that much harder than the Technician class, and you can take it in the same sitting for the same money if you first pass the Technician test. Use the free online test practice tools until you can pass consistently. Get your ticket. Get on the air. NOW start studying so you really understand the material. Because you are on the air, you will know better which areas to really learn about. Anyway that’s what worked for me.

    nick

    • Doug says:

      Thanks Nick.
      I’m getting there. Lots to do… lots to do 🙂

      I built my own wind turbine/solar system charging a 12v fork truck battery. Have lots of reserve amps as it is an industrial motive battery built for an 8 hour duty cycle. I’m going to put an antenna on the turbine tower for my base. I’ll be pretty close to the highest point for 30 miles. As an aside, somebody mentioned to me a rotating set of aluminum turbine blades has unique antenna properties for short wave. You ever hear anything like that?

  6. Badger says:

    Thanks for the breakdown. I’ve been running an OCF for a few years & it’s a Clydesdale, with performance as you describe. I have noticed something that may/may not be of interest to some if they’re deciding how to orient such an antenna for a fixed base. (If they have the room, I chose mine for the same reason you did; location of the feedpoint and some lot constraints here dictate orientation.) Curious if you have noticed any similar or slight bias in performance as regards orientation of it.

    Living in the upper Great Lakes region primary concern would be east/west/south; less concern with talking with the Yukon. If I’d had the room I’d personally orient the antenna with the long segment pointing south (more or less) and the entire wire broadside to east/west.Not that it doesn’t work northward, it does. Someone in the deep south may want to reverse that. I just notice slightly better listening performance off the long-end of the wire & of course the broadside aspect works great. The goal would be to orient it to the 3 directions that are most important based on location; again, it works terrific all the way around the compass. Just something I’ve noticed after documenting lots of contacts and being able to get critical signal reports from them, applied to a map.

    Gotta love wire antennas; once up, anyone in the area quickly forgets about it because, like deer, they seldom look up into the deciduous jungle.

  7. david allen says:

    Building and lot layout doesn’t allow for a center feed antenna. Currently using end fed “long wire” terminated to a tall tree. Up 30′ at the end, 18″ at feed point, 185 ft long. Use a SCG #237 tuner at the end of the antenna. Then 55′ feed line to the shack. Also has counter-poise wire in the ground. Icom 7200 transceiver.

    Don’t forget to install some sort of lightening protection.

    Always looking for new ideas….

    • danmorgan76 says:

      Man, I am jealous. I have lusted after the 7200 for a while now. Good buddy has 2. I asked him if he would take the wife in trade for one. He didn’t bite, dammit.

  8. PSYOP Soldier says:

    Outstanding article, thank you…

    I am currently studying for my Gen ticket and am in RX mode on my hf gear…The gv5r jr dipole is another good antenna as is the 34′ end fed 6-160m https://amateurradiostore.com/index.php?main_page=product_info&cPath=2&products_id=196&zenid=nkpgptu1cvn1d6ltn9ioo8q8c3

    I will be installing this antenna very shortly, good for those, like me, who live in HOA restricted ‘hoods, as it is very discreet, almost impossible to see once in air…I already have my VHF/UHF antennas in attic with good local coverage…

    One point is that one doesn’t need a gen license now to buy, set up, configure antennas, learn equipment and LISTEN ONLY while at the same time, study for gen ticket….Hook up with an Elmer/Mentor and soak the knowledge….

    Like you, i plan to use NVIS as well, given that i live in Charlotte, and am NOT concerned with DX’ing to Russia, but NC/SC/GA/VA/TN…

    DM, you are spot on as well regarding folks who think they can go buy kit, stash it, and then automagically “figure it out,” when SHTF…Not gonna happen..The time to learn is NOW, before a magic moment arrives,,,,

  9. PSYOP Soldier says:

    DM..

    Here’s a link to a good article for newbies on VHF/UHF if you feel compelled to review and post for guys like Doug et al… https://informops.wordpress.com/comms-101/

    • Doug says:

      Thanks,
      read that essay a few weeks back, found it very useful. Glad you think highly enough of it to recommend it.

  10. idahobob says:

    Thank you for the great info! the terrain in my AO is very similar……..straight up and straight down, and the ridge lines have no pattern, it is a jumbled up mess.

    As I am a fairly new General, and encouraging my “buds” to up grade, NVIS is the way to go here for “local” coms.

    Again, thanks!

    Bob
    III

  11. dangero says:

    I doubt that it beats your system and it’s probably a little more all told cost-wise but I’ve had great luck transmitting on a 40 m NVIS setup with my Buddipole. I can have it up anywhere in about 15 minutes and it only uses about 35-40′ of space. Directions here:
    http://lib.store.yahoo.net/lib/buddipole/nvis2008.pdf
    I didn’t get good results using PSK31 with this setup but voice is very good usually. I’m going to explore some other data modes that are more error proof.

    • Keypounder says:

      Dangero:

      PSK does not do well on NVIS, as the multipath nature of NVIS gives PSK fits.
      I am looking into using FSQ, Olivia and Contestia for NVIS digital modes.

  12. pnoldguy says:

    Excellent post. I just passed my General last week. Looking forward to reaching out. My antenna is my weak link but I’m working on it. Thanks for the great links!

  13. Gary says:

    The problems I face is that a) limited on space, since I’m in a neighborhood and the utilities are routed behind the house ; b) shunned more experienced hams, since I’m not into contesting and finally c) new to the HF game.

    I guess I just have to experiment.

    Thanks for the articles Dan.

    http://WWW.TYRGROUPLLC.COM

    • Keypounder says:

      Gary, the neat thing about NVIS is that you do not have to put the antenna up high at all for it to work. If you have a wooden fence 4′ high, just lay an 80 meter dipole on the top of the fence. It will work. Heck, just lay the antenna on the ground, and it will work.

    • danmorgan76 says:

      Gary, take a gander at the antenna that Psyop Soldier listed in the link below. The J-Pole Sr. It is only 34’long, covers every band and can be used in the NVIS mode. I think it’s my next purchase. It will require an antenna tuner for optimal power transfer.

  14. oldgreyguy says:

    Look up the plans for an End Fed Zepp. 135 ft long if you can. Shorter if you must. Does NOT need to be a 1/4 or 1/2 wave. Does NOT need to be strait. Use 450 ohm ribbon wire and an antenna tuner with a balanced line output. Will load and radiate.

    Licensed for 57 years.

  15. freebird says:

    Great article! I’ve got my general ticket…just need HF transceiver. Does anyone have affordable suggestions?

    • danmorgan76 says:

      You’ve opened Pandora’s Box. Just like asking what’s the best car or gun manufacturer. I prefer ICOM. Some folks are Yaesu fans, while others swear by Kenwood etc.

      For my base I use a simple, been around for years, tried and true (notice how I bragged that up?) ICOM IC-718. With it use the LDG IT-100 tuner. Entire rig runs about $750.00.

  16. PSYOP Soldier says:

    Please remove or move if not in appropriate place….

    For those of you new to amateur radio, especially HF, and or on a limited budget, please consider buying used kit at a local hamfest, from a reputable dealer and/or local hamclub member…that is what i recently did and acquired a perfectly good hf rig from a deceased ham operator estate: Kenwood ts-440s w auto tuner, an external mfj 949b tuner, Astron 35a power supply, and a mike, all for 400.00…unit sits on my desk, but is mobile (vehicular) capable…Good first rig for a newbie like me…New everything would have cost 1000+ $$ so i am very happy..

    Now, i get to play/experiment with various antenna configs and learn my radio while i study for my gen ticket, as there is nothing preventing me from listening, and i can always bring a fellow hambonz mate, using his license, over to key up and talk to really test it out…

    As always DM76, great info, presented well and easy to understand…

    73’s all..

    ps..i will provide post Alpaha Sr antenna installation and analysis info….

    • danmorgan76 says:

      Freebird asks “How much power is needed?”. You probably won’t like my answer. I have made comms (CW) from a cow pasture in Honduras, C.A.,using a barbed wire fence for an antenna, back to Ft. Bragg with 20 watts on a PRC-104. I regularly share data with a friend on our local net at 0.1 watt. He is about 60 miles away as the crow flies. Others one the same net, the same distance away I can barely hit with 50 watts.

      I guess my best answer is to have all the power you can get available, but only use what you need to make the shot.

      • PSYOP Soldier says:

        Freebird et al: As DM76 pointed out, very little power is needed to communicate via HF, some folks specialize in QRP or low power, mainly CW (morse) but for the average joe, looking at voice comms, anywhere from 10w on up…My rig is 100w, which seems to be the norm, some rigs less, some more…The overall goal, as my newbie mind comprehends it, and agrees, is to use the least amount of power to achieve comms…Trial and error…Antenna theory and application is your friend…

        Remember, you may be using a 12 car battery if need be, so be judicious and skillful in power consumption now, before you are forced to in a shtf moment…Time to learn and do is now, before an event, while you can w/out the added stressors, imho….

        Keep in mind, that one can use a directional or Yagi antenna, and use far less power to achieve comms, as it focuses the energy..Example would be using a 5w HT with Yagi, to communicate to the space station….that is uhf/vhf stuff, not HF, but the general principle applies….

        Per DM76, HF comms are vastly different, for a variety of reasons than VHF/UHF, and once must know the strengths and limitations of each mode…

        I have local comms covered with VHF/UHF rigs from 5w ht’s for neighborhood/tactical comms, to kenwood 2m rigs for local regional using both repeaters and simplex, out to HF comms…A multi layered approach is what i strive for, add in SDR and Digi Scanners and a good SW receiver, and i have a good blend of both TX and RX….

        PSYOP

      • Freebird says:

        Thanks Dan. I’ll buy that. So my next question is if I had an all band all mode radio with 100 watts of power intending to use sometimes for NVIS…that should be plenty to hit 30 – 300 miles out… Right? And if that’s the case does power help to overcome other deficiencies in skill and/or specialized equipment?

      • Badger says:

        Freebird, under average conditions your 100w will do the job. And in modes that have even narrower bandwidth than SSB voice it’s more than enough. You can do CW on miniscule amounts of power and I routinely make Winmor connections in somewhat poor conditions on 20-30w. Your questions are good ones but are linked.

        Power can overcome extremely poor conditions to a certain extent but only to the point of being able to hear the return call to you. That is, you may put out a powerful signal using an amplifier but if your antenna solution can’t hear the other end what’s the point? NVIS is not a mode, it’s a technique for actually getting your signal to come back from the atmosphere down into the area you want. (Think of a mortar vs. a long-range missile, or tossing a rock into the air vs. skipping one across the lake if that helps.) It’s possible to run really high antennas and “skip” over your destination. Great for talking with Spain but is he going to come over & give you a hand when SHTF? This is stuff you will learn in playing with antenna height and actually getting on the air. Whenever someone asks me first where to put their resources, antenna capability or power, my answer is always “antenna, antenna, antenna.”

        Get ticket, get on the air, learn, apply, repeat. 🙂

      • Freebird says:

        Excellent tip thank you! So if I read into that vorrectly antenna height has an effect on propagation angle… Right? So if I want to make relatively close contact them horizontal antenna should be closer to Earth, and for farther away contac antenna should be higher of the ground, or inverted V…Right?

      • Badger says:

        In a nutshell, you got it. (Except an inverted-V is just a type of basic dipole antenna, can be high, low, in-between.) I would suggest you grab the study guide(s) probably referenced at this site or to be found at the ARRL website and things will become clearer. A couple of good PDF’s to have around are both USMC publications. MCI 2515H is a comms primer. The better thing is MCRP 3-40 which is the Marine Corps’ version of the fine DoD Antenna Handbook prepared by the AF and a bunch of scientist types – most of the Army versions I’ve seen have illustrations not even good enough for Bill Mauldin. (For all their reputation as neanderthals sometimes, the USMC version has the best illustrations.) The antenna handbook can be found here:
        http://www.zerobeat.net/r3403c.pdf

        Perhaps even contact an operator in your local area who can get you started. When you’ve gone thru some studying start banging the hell out of the free online practice tests, then find the next testing schedule in your area (also available from ARRL). Then the real learning begins. There’s some bread crumbs; have at it.

  17. Chris says:

    Freebird, I have multi-year good results using NVIS with a 20W SSB rig (SG-2020). This is on a regional 80m net using a 130′ wire up 17′ at the center and 8′ at the ends. It’s fed with window line, and I use an SG-237 tuner to drive it. Works well from local out to 250 miles or so.

    • danmorgan76 says:

      Freebird, You are correct regarding antenna height and propagation angle. Even an inverted V can be used for NVIS if the ends and center are lowered.

      • firebird says:

        Sweet success! Thank you all for your contributions and getting me up to speed. I already have my general ticket so just needed equipment to put it into use. Did that a couple of days ago with a Yaesu 857d with an LDG YT – 100 tuner and a g5rv dipole antenna cut to 80 meters installed horizontally to ground about 3 feet off ground with reflector on ground. Worked wonderfully! Made contacts as close as a couple of miles out to a couple hundred miles away. Experimenting this weekend with a “cloud warmer” NVIS beam antenna that can be found here http://www.hamuniverse.com/nvisbeam.html

        Thanks again and 73s all around. Will report on my experiment results next week. Stay tuned!

        FB

  18. PSYOP says:

    Alpha Antenna Sr initial review: disclaimer..I am NOT in any way associated with Alpha Antenna other than a very satisfied customer.

    Also, i am new to amateur radio, having my license a bit over a year now, so i know nuttin compared to DM76 and many others…My criteria is that is has to work for me, the first time more or less…I am progressing in my knowledge, but have to rely upon others/Elmers too.

    That said, i live in a suburban setting, hoa controlled, homes in close proximity to one another, single story ranch and needed an HF antenna that would allow me to reach out regionally/nationally if need be. I have local/regional UHF/VHF comms covered fairy well.

    My hf rig is a kenwood, older ts440s w auto tuner. 100w. pretty basic unit, bought used from a dead key estate. perfect for a newbie…

    After much research/reviews read, decided on the Alpha Antenna Sr, HF end fed, 34′ 6-160m rig for my solution…..Pricey at 150.00, but worth every penny, built like a tank, well made, solid construction all around.

    First thing i did was to hang it from my decorative flag pole on the front of the home, approx 10′ up, and the end tied off to a tree, at approx 7′ off the ground, so kinda sloping/nvis set up. Ran feedline, radio shack rg58, thru window into office, connected to radio, and shazam, comms….i was able to scan and pick up conversations on 20/40/80m quite easily.

    made a couple contacts too, in se us and near chitown, good signal reports. Perfect for my needs.

    I then tried another redneck mast system, a 23′ extendable painter pole zip tied to a tree, raised to 16′ and end, still tied off to other tree, but more of true sloper this time, and observed better signal/tx/rx performance.

    Ultimately, this will end up in my attic, out of sight, out of the elements too, and i forsee no issues with this config…the antenna will run north to south along ridgeline…

    Steve at Alpha was very responsive, helpful to a newbie, patiently answering my basic questions.

    This would make a great portable/field antenna too, imho..

    So, to sum up, a great antenna, no tuning required, well built, good performance, easy to deploy and install, especially for a newbie, and made in the USA….What more can a person ask of a product?

    I would not hesitate to buy one, or two if one can afford it…..

    73’s all..

    PSYOP

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