The Broken Quad Antenna

Designed by KJ7EZ
     The material you'll need is as follows: A vertical antenna
  that is 16 foot long, I used a Hygain VS18 80-10m trapless
  vertical. Also you need, 40 feet or two sticks of PVC 20 foot
  long each. I would recommend Sked 40 at 1 inch in diameter.
  You'll also need to get a 4 way crossover (PVC) and a Tee also
  one inch. One inch seems to be strong enough to make a descent
  antenna. You'll need a total of 133 feet of wire (if your going to use
  it for more than just 20 meters), I recommend insulated wire,
  if you touch one of the other radials, your SWR rises. You need
  a piece of pipe (I used an 18-24 inch piece metal conduit).

  (1.) Cut three pieces of PVC into 7 foot sections and one piece
  about 6 foot 6 inches, and one small piece approx. 3 inches to
  allow you to attach the Tee to the 4 way crossover. You'll need
  one last piece about 18 to 24 inches long (your choice).
  This is what you want to mount the vertical to. Slide a piece
  of metal pipe (your choice again I used 1 inch conduit or EMT)
  into the 18-24 inch piece of PVC for extra support for the

   (2.) You have a choice at this point! You can glue these pieces
  of PVC together? Or you can just push them together or drive
  them into the 4 way crossover and Tee by hammering them in
  using a piece of wood (a 2x4 block). This depends on whether
  you want to make it a portable set-up, or somewhat permanent,
  although moveable.
  (3.) Take the 3 inch piece of PVC and drive or glue it into the 4
  way crossover. Then put the Tee onto the other end of the 3
  inch piece PVC. Make sure that if you glue these points
  together. The Tee will allow you to put the 6 foot 6 inch piece
  of PVC extended out in a big X or plus sign. Make sure you get
  the Tee on a "FLAT" side of the 4 way crossover, so if you lay
  the crossover down you can look into the other opening of the

  (4.) You can now either run your wire for the radials or mount
  the vertical? Whichever you want to do, either way, the vertical
  is not in the way of running the wires. I mounted the vertical
  with the wires attached to the vertical, so I'd have that much

  (5.) From the center of your X or plus sign, allowing enough wire
  to be used for connecting the radials to the vertical. Run a
  wire out to the end of the arm of the X. You can do this
  however you'd like, I taped mine, since it was the prototype.
  Attach the wire to the end of the arm using tape, or a strap
  (plastic) or you can even drill a hole and feed it through. You
  should have a little over 8 feet of wire left over at the end
  of the arm. After attaching it to that arm, run the wire over
  to one of the next arms closest to that arm. Attach the wire
  again to the end of the arm, on the side of the PVC. Whatever
  is left-over at this point (a foot or two), run it back down
  the arm you just attached it to, toward the center where the
  arms come together.

  (6.) After running your first wire, just repeat that step for
  the next three radials. Then repeat this step for as many
  of the bands you want to use, onto the PVC arms. Be
  careful not to touch the wires together (physically), and don't
  connect the ends of the wires to each other in a loop fashion. I
  recommend insulated wire be used. To save on wire you can go
  out from the center about 40 inches, and make a splice. You can
  run any remaining wire for other bands from this splice. Just
  remember to deduct the 40 inches from the total length of the
  wire for the band it is to be used for. The splice is made on
  the original first wire run on each arm of the X or plus sign
  that you cut for 20 meters, which will be 16 feet long each
  total. Just remember to cut your wire to resonance for the band
  you want to use it for. Remember that they will only be a
  quarter wave-length long each.

  (7.) If you touch the wires together along the arms, except at
  the splice point. It will cause your SWR to be high. My SWR for
  this antenna is: from 15.000.00mhz it is 1.5:1. At 14.350.00 to
  14.100.00 it is 1.1:1 and at 14.000.00 it is 1.2:1. It finally
  reaches 1.5:1 again at 13.650.00mhz.. You can tune it for 17, 15,
  12, and 10 meters however, you will need to run separate
  radials for those bands. Using the same method, try not to let
  them touch the longer wire either (metal to metal), it changes
  the length of the wire. just like on a dipole when you touch it
  with another wire someplace other than the feedpoint.

  (8.) Just think of it as a "BROKEN QUAD" antenna! It looks like
  you took a full-size 10 meter quad after the boom broke.
  And you couldn't salvage it into anything else, so you made a
  set of radials for a Ground Mount Ground Plane antenna. You can
  mount this to a tower if you'd like. But mine is sitting on the
  ground, which puts the feedpoint at about 2 inches off the
  ground. The arms of the X act as legs to support the vertical
  I have heard more on this antenna than any other antenna
  I've ever owned. I have worked 8 new countries on 20
  and 17 meters with it, and it's only been on the air now for
  three days and I haven't even been trying hard. I have gotten
  those countries on no more than the third call, only running
  100 watts from a TS850.

       You could probably make a set of radials for 40 and 75/80
  meters just by making the X bigger. You could put up a trap
  vertical with this underneath. And it might make a good antenna
  system for those of you who have antenna restrictions? Maybe
  you could cleverly disguise the antenna as something else like
  a broken (or working) Teather-Ball setup?

       I hope this antenna works as well for you as it does for
  me? I'm very happy with it, and if you put it on the ground like
  I did. You can move it when you have to mow the yard! Or until
  you find the best spot in the yard for it to have maximum
  performance. It works well into Japan and the South Pacific and
  very well into Europe and South America from my QTH (DM16RP).

  You can modify this design if you need to. You can use a Trap Vertical
  instead of the one I used. You can enlarge it to suit your needs for the
  band you want to use it on. It would make a nice portable, "take-down"
  type antenna system for Camping or Field Day or a DXpedition. It would
  also be good for those who have antenna restrictions, due to legal
  reasons or weather. You could fasten it down, once you find the location
  in the yard you want to leave it in, to keep it from blowing over in
  really high winds. And you can move it when you need to mow the lawn hi
  hi. This version of the design only needs about a 14 square foot area of
  the yard. Just remember your wires will be within the extended arms of
  the Broken Quad Antenna.

  If you can improve this to be even more efficient let me know? I intend
  on keeping this system around a while, and anything that will improve it
  will be appreciated. You can send me an email at this address: clifflp@ or snail mail. You can send it to just the information below,
  the local mailman is a Ham also and close friend.

  Hope you will have a lot of fun with that antenna!

  Designed, tested amd in use by Cliff (KJ7EZ)

(This file came from the packet network).

Frank, G3YCC

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