Two From Brushbeater

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Radio Station Grounding

Milsurp Mast System

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7 responses to “Two From Brushbeater

  1. Keypounder

    Milsurp mast systems can be very useful, and I have found a tripod assembly that works well with either aluminum or fiberglass-https://www.goverticalusa.com/collections/antenna-mast-sections-tripod-and-base-camo-pole-section-kit/products/antenna-tower-aluminum-tripod-base-for-use-with-military-48-mast-pole-orange.

    Combine this with clamp-on guy ring sections from Rohn, and you can erect a 50′ high mast in 10 minutes with 4 people, or do a single guyed 25′ high mast in 5 minutes with two people.

  2. New to comms here. Good post, thanks.

    So insanely ovewealmed with this new world i just stepped into. My little baofeng in learning on right now doesn’t seem to have much range. Onto bigger and better stufd i guess…

    • Henry Bowman

      Stewie, we all were there, and are in various ways..I am not a qrp guy, so i feel overwhelmed, etc…just keep plodding along, it will become more clear as time and experience develops..Keep learning and asking, no shame in that…we are here to help..this is great article to read on comms 101.. https://informops.wordpress.com/2015/03/22/comms-101-vhf/

    • Keypounder

      Stewie, everyone starts somewhere, and you are starting where lots of others have done. My first rig was a two tube homebrew CW transmitter and a Heathkit GR64. The transmitter put out 5 watts, and I had 3 crystals for it, on 80 and 40 meters. You are way out in front of what I could afford when I started over 40 years ago; I did not get my first two meter rig until I was in my twenties. And I am still learning about the new digital modes and what they can do; I doubt there will ever come a time when I have nothing left to learn.

      When it comes to getting your signal to where you want it to be heard, and hearing the reply, propagation is 100 db, terrain is as much as 30 db, the antenna is 20-30 db, the transmitter and receiver about the same (15-20 db each), and the microphone and headphones each about 5 db.

      You cannot control propagation, and your terrain is what it is where you are. (You can pick terrain optimal for your particular band and mode, but that is a LONG discussion, and presumes the ability to actually make the mission conform to terrain requirements, not very likely) The biggest single factor over which you have control that can boost your ability to communicate is a good antenna, followed closely by the best receiver you can afford. Power comes with a steep price, especially with portable ops, including:
      -increased probability of intercept and location;
      -reduced mobility (batteries are heavy and so are generators and fuel)
      -increased IR signature (half the power used is radiated as heat)
      -increased use of resources, especially manpower

      All of that is a very longwinded way of saying that the first thing you want to do whenever possible is deploy a better antenna. That is as true for LOS VHF/UHF FM comms as it is for any other band or mode. Keep in mind that shorter wavelengths are more readily absorbed by foliage and vegetation, so Brushbeater’s advice to keep the antenna as high as possible above the trees is very sound.

  3. Ye olde veritical half rhombic antennae was par for the course, circa 1973, when old Sarge attended the Infantry/Armor Basic NCO course, Ft. Benning, Ga. Three months of really sloppy instruction, but for those who wanted to pay attention, damn good stuff to know. Anywho,this thing can extend your radio nearly three times it’s usually range. Dig it.

  4. Alfred E. Neuman

    Reblogged this on ETC., ETC., & ETC..

  5. A similar field mast kit can be made from camo net poles. From a pole kit of twelve 4′ poles, four spreader assemblies, a dozen stakes, and some other goodies- a spreader ass’y can be sacrificed and modified easily to make one or two guying plates and a coax/balun/radiator support plate.

    I run six sections of pole for a field dipole (AS-1743 multi-band reel). Six sections nested gives a feed point of 22′ above ground. I use a guy plate with four cords halfway up the mast. On top, there’s a simple hoisting point for coax, balun, and wire. The wire stabilizes the top of mast in two directions, and two cords stabilize in the other two.

    I can get this up cut for 75 meter band in half an hour by myself. It has withstood some winds above 50 mph.