ShopTalk Sunday: Antenna Season Arrives!

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Wow.  At last the heat is backing down and the radio season is here.  When the bands go through their change from summer to winter.

Generally – in he northern hemisphere – in the summer, the higher radio bands like 20-meters are open a lot of the time.  But, the “old boys nets” in the early morning (and late nights) on the low bands (80 and 160 meters) tend toward much higher noise levels.  Static.

Every year around this time, thousands of hams begin thinking about antenna projects to support whatever their specialized interests might be.  Low bands – 80 and 40 meter optimizations probably lead the list.

This week, I decided to put up (“fly”) the new double-sized W5GI “Mystery antenna”.  It’s big but it does some great things.  Like give some gain on the 40-meter band – prime X (long-distance) Morse and digital modes over winter.

80-meter antennas are a worthwhile endeavor – especially if you like AM – in which case the 3.885 MHz national calling frequency is a good place to listen.  As I’ve explained before, AM (amplitude modulation, but also called “ancient modulation) involves a carrier frequency on which two “sidebands” of audio have been impressed.  The other popular voice mode on the low frewuency ham bands is single sideband (SSB) and involves equipment that nulls out the carrier and one of the sidebands.  This means much more “talk power” for a given power level, but it requires the now suppressed carrier be recreated locally to understand the signal.  This is done with a beat frequeny ocillator (BFO) which is best applied to a product detector, although the AM-friendly diode detectors can be OK until they overload. At which point it sounds god-awful.  Anyway, all baseline stuff.

In general, the higher you can get an antenna, the better it will work – with one exception.  Daytime, on the low bands, propagation is easiest with “near vertical incidence skywave” [NVIS} propagation.  That’s because during midday periods, you want to squirt as much signal straight up so that the ionosphere provides something akin to backscatter.  Which is thought of (in the micrwave frequency range) as “troposcatter.”

Putting Up a Beast

The “double W5GI is about 200-feet long. Step outside with me and we will take down the old off-cnter-fed dipole (OCFD) and we’ll put this bad boy up.

I used of of our drones, hauling some 30-pound test SpiderWire fishing leader, up over a couple of tall trees.  The west tree, I maneuvered the line into the highest notch I could, like so:

And on the east side, it went into this tree because the tallker one on the right, I still have plans for…

The eastern tree is easy to get to, but the west one has a short trail to it through the brush:

The “downhaul” is attached to the tree with an inch-and-a-half stainless steel eyebolt.  You use these so that when the tree is harvested (somewhere in the future) you will be able to remove the metal, so the tree doesn’t cause an accident for a sawyer or a mill.

Sharp eyed antenna inspectors will see two lines are tied-off here.  One is the “bitter end” of the line (we buy paracord in 1,000 foot spindles – we use a bit).  The one up and to the right is the antenna end.

After Elaine helped get the low parts clear of a storage building and the other clear of the solar panels, that left nothing but the center feedline to connect to coax.

There’s nothing serious inside the PVC, the center of the coaxial line goes to one side of the ladder line while the outside (shield) goes to the other.  There’s about 50-feet of twinlead and yes, this is why higher is better.

With a 40X digital zoom setting, the top looks like this:

The line running off to the right is the center raising halyard – and it doesn’t look like the usual “going up” because I set it to get the antenna as far away from the tower as possible.  Towers tend to absorb energy  so good practice is to keep antennas 4-6 feet from anything grounded.

Out at the ends, one the west side that eye bolt holds the line and on the east side a convenient fence is used as the tie-off point:

Decoding the numbers:

  1. This is the line that goes up to the tree top (tension on the antenna)
  2. The “bitter end” is tied off.
  3. Even though it looks like a mess, this whole rats nest can be strung out straight in a minute, or so.

Putting up bigly to hugely antennas is easy with you “get creative” with your lift.  Drones are one of the best ham radio inventions ever.

Still to come this winter:  Trying to decide whether to put up the 80-meter double bazooka or the 20-meter optimized W5GI.  The final antenna for this winter will be a very long (246 foot on one side) off-center fed dipole.

This one will run north-south because OCFDs tend to be end-firing, depending on height over ground.  This one will be fed with 450-ohm ladder line, too and should give good enough performance that (with luck) Hank might be able to hear it out in Hawaii.

We shall see…

Still Ahead Today

Lawn more spindle has been replaced – so that’s back in service and calling to me for a trim.  I put off going to Lowes to get the rest of the wood and stair stringers for the deck, but the good news is all the computer issues have been nailed now…

Weekends and working with your hands is a good thing to get used to…you never know how long civilization will remain “civilized.”

Write when you get rich,

George@Ure.net

39 thoughts on “ShopTalk Sunday: Antenna Season Arrives!”

  2. Weather’s a funny thing. My last comment related my week of temps at the end of August, which showed highs in the high 60s to mid-70s, with stupid humidity.

    I think my current weather pattern will break today. I’ve had 11 days in a row of highs between 89 and 96, but with humidity ranging from 18% to about 35% (yesterday was 18%RH@94°F, at 1500hrs, which is downright pleasant in the shade, even without a breeze.)

    • amazing videos – the forest one (first vid) was best – really love to see someone do something innovative with the hobby!

      BTW heard but didn’t have time to work a YH (Indonesia) station with the 40 meter w5gi senior today…an’t whine about that!

    • Israelis have been doing this for a couple of decades. Dry sand works better than wet dirt. (Surprise!)

      Once we did deliberate tests of a plain center-fed dipole with a pair of trpiods equipped with pulleys to allow flying the antenna at any height. We were doing NVIS testing with known stations from one town over, out to about 200 mileas. 80 meter and 40 meter daytime.

      Performance was nearly height-independent.

      The lowest we could adjust was to about one foot off the field. (Middle of football field at high school.) 100 watts PEP — though much less also worked just fine.

      The coax feed was just draped and dribbled across the earth to the table.

      We concluded for dayime NVIS, height almost didn’t matter at all.

      73
      KW1B

        • With 180 ft of wire (north south) and on 20 meters with the band open, it would do a db better than a half wave dipole. Takeoff angle would be crappy – around 30 degrees depending on moisture in soil. Now, if you could find a 90 feet tall fence, better than 10 dbd (12.2 dbi) and a 10-degree take off angle…

    • For receiving, the LOG, or Loop-On Ground is the best low noise antenna you can get. About 15ft on a side, square, is what works best for me. Don’t really need an amplifier, either, but there are versions of both.

  4. Garlic is planted like tulips, before (hard) frost here. Will be planting this week. Got all the prep done.
    Have extra garlic for seed or eating, so just put offer on marketplace, wife’s login.
    Vic

      • Not very long after nine-eleven, we were outfitting a new Emergency Ops Center (the fear money was still flowing freely) for our little suburban town. Ridgefield, CT is Oz, and a bedroom community for the Big Apple. Ridgefield lost about 25 citizens on nine-eleven…

        Anyway…

        First Selectmen (mayor) asks us how many antennas we need. (I had designed an Sauguaro Cactus-like thing to hold them — three mounting points each at 25 feet up, of 2-inch black cast iron pipe.

        I replied, “…about twenty.” He was amazed and flabbergasted. (He was thinking maybe three.)

        We needed antennas for State CT EOC, Local FD, Local PD, a couple of ham, Red Cross Low-Band Nationwide – 42.42, and numerous others. We were also tasked to be backup dispatch points for several services. Each needed a”position.”

        I don’t believe in scanners, because it seems there is always something unimportant they’re stuck on when something vital and urgent needs to be heard… So, my doctrine was, “One Service: One Antenna. Each.”

        Turned out by the time we covered all the imperatives, including the school bus fleet, and the Selectman’s Ego Private Command Channel,
        twenty wasn’t enough. We used discones that covered from 30 to 450 mHz.

        Excellent performance from our minor hilltop, and with discones, any antenna could be used on any service Lo VHF, Hi VHF, UHF, “700,” whatever. (RG/8 Patch bay)

        A couple of simple wire antennas covered 80 and 40. We didn’t think any other ham HF bands had much of an emegency communications role… Still don’t. “Relief” comes from the next town over, or from the state capitol: NOT from Australia or Europe.

        We were careful to include CB because
        Relief”comes on trucks: and trucks all have CB.

      • Interesting stuff for those with time to spend on it. I wonder if anyone is planning to try the moonbounce thing with the new “temporary moon” that NASA is assuring us we will acquire. That’s a small target though, and a fast moving one. Radio has done amazing things since the days of the spark gap, so it wouldn’t surprise me.

        Now I’ll get back to figuring out an adequate fix for a horrible design on a car – putting essential relays low in the fender well where even a slightly flooded road has them underwater!

    • MARTIN ARMSTRONG: For the first time in modern history, Switzerland’s population has surpassed the 9 million mark. We’ve seen the same phenomenon happen throughout the West. Populations are rapidly growing despite low birth rates, all due to immigration.

      Over 27% of Switzerland’s population is now composed of migrants, with immigration increasing by 11.7% in 2023.

      Under European Union guidelines, Switzerland first opened its borders to foreigners in 2002. The People’s Party unsuccessfully attempted to curtail newcomers in 2014. Then the EU stepped in and forced all member states to adopt open border policies.

      There is a steep cost associated with a boom in the population. No one dares to question how this drastic change in the population will change society itself as many of these newcomers do not share the same traditions and values as the native Swiss population.

      https://www.armstrongeconomics.com/international-news/europes-current-economy/switzerlands-population-surpasses-9-million/

  8. On Hal Turner’s site now:

    “It is apparently official: Hezbollah units have, within the past few minutes (11:21 AM EDT Sunday), all begun raising the Red Flag of War. This is taking place over such a widespread area, and at the same time, as to logically be “official.”

    Given Israeli bombings all across Lebanon for the past three days, and the deliberate detonation of pocket pagers, cell phones, and walkie-talkies in the days prior to that, it has been clear to most observers that war has already been foist upon them. This gesture, with the Red Flags, is apparently acknowledgement of what has been obvious to most people, for days.

    Where things go from here seems obvious too: Down hill. Fast.”

    • George Ure: Weekends and working with your hands is a good thing to get used to…you never know how long civilization will remain “civilized.”

      Panic In Year Zero (1962)

      Ann Baldwin: What do you want to do, write off the rest of the world?

      Harry Baldwin: When civilization gets civilized again, I’ll rejoin.

    • “Back when Bernard Whatzizname was diving under desks in Bagdad at odd hours (1990s?) my wife, Kathy, inaugurated a phrase: “The War Show’s On, The War Show’s On!!” (Meaning no disrespect.)

      Since then, I have always had a TV Nooze channel on 24-7, monitoring for, as I say, “incoming asteroids, and VIP assasinations.” Zero volume on the sound. Fox, usually, as being the “Best of the Bad.”

      Good for very bad sudden weather, too…

      I also keep an AM radio tuned to 0.500 mHz with very low volume as a lightning dectector and warning.
      (Ligtning static bursts peak up around 0.300 mHz for dectection purposes — good for about 25 miles.) 0.500 mHz is close enough for monitoring.

  10. Personally, I consider the Israeli counter-terrorism attack, using pagers and radios as weapons – as brilliant. A masterful use of psychological warfare. One of the best ever perpetrated in modern times. All of southern Lebanon is now in fear of their mundane, every day, taken-for-granted, inanimate electronic devices.
    Someone in the Israeli government said: “Phase One is now over.”
    Makes you wonder what Phase Two is ? And how many ‘Phases” are there ? Or.., is that just another part of the psych-game they are currently playing with ‘Phase One’ ? Which in-itself is brilliant.
    Gotta love international, battlefield chess.. !!

  11. Six meters (50MHz) opened up yesterday afternoon for a path from the islands here to Santiago, Chile. Two contacts at 100 watts on the (what else?) IC-7300 on a Hexbeam.

    NVIS on 40 meters is what keeps us all in contact along the entire island chain here… some 300 miles across. Three daily nets keep us in practice, and learning the variety of NVIS propagation. In a pinch, we will still have inter-island communications.

    Couple years back I had a 40 meter contact with a fellow in Indiana who had a 14-element wire beam aimed SW. He must have had several football fields of property strung with wires. He was S9 into the Big Island here. When are you going to string out that 8-point Rhombic, switch selectable, so we can talk, George? ;-)

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