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Gary Slagel
NØSXX


This is an antenna I designed specifically for operating from the summits of mountains.  The environment at the summit is unique. Naturally, there are no trees to string wires in. The ground is usually pure rock without even a trace of soil to hold a stake so it's difficult to put up a pole with staked guy wires. The thin air leaves an old guy like me gasping the last several hundred feet carrying just myself up, let alone a lot of extra ham radio gear. So, my requirements for an antenna were to be very lightweight, easy to carry AND completely self-supporting.

The design is based around a hustler resonators. I've used it on 20 and 15 but it is equially usable on any band you have a hustler resontator for.  (I'm sure the bigger resonators will not fit in the PVC case for carrying though) The general idea is to mount the resonator on a piece of 1/2" copper pipe. A piece of 3/4" PVC serves as a short mast for the antenna so that it could be slightly elevated, allowing me to have elevated radials. The PVC mast has a tripod at the bottom made of 3/8" threaded rod, which is simply pushed through holes drilled at an angle at the bottom of the mast. Feed line and radials are connected to small bolts put through the PVC and copper pipe. Three 1/4-wave radials are attached at the site using alligator clips. For hiking, the copper pipe slides inside the PVC, the 3 threaded rods slide inside the copper pipe and the resonator slides into the PVC on top of the copper pipe. One side of the mast has a permanent PVC cap and the other side has a screw off PVC cap. The whole thing functions (poorly) as a walking stick when packed up.  As a walking stick, its is probably a little long and a little heavy.  I generally don't use it for walking except when I'm coming down the mountain, it is occasionally useful for bracing myself as I come over large steps down.   It sets up in about 2 or 3 minutes.

To the left is  a sketch of the antenna setup (I forgot to draw the resonator but it, of course, sits on top of the copper pipe).  The overall height ends up about 10' 3" high.  The radiator portion of the antenna is just under 7 feet with the 20 meter resonator installed.  The feed point is 2 #10 bolts slid through holes in the pvc, the coax shield attaches to the lower bolt and the coax center attaches to the upper bolt.  Radials are clipped onto the lower bolt using alligator clips.  I carry the feedline and 3 radials in a separate sandwich bag.  The feedline has the 2 bolts attached to it.  The copper pipe simply slides into the PVC and rests on top of the upper bolt to provide the electrical connection.  While this method of electrical connection may not seem terribly stable, it has never caused me any problems and it DOES provide for very fast and simple setup.  Making the tripod requires drilling holes through both sides of the PVC to accept the threaded rod.  The holes should be at about 30 degree angle to the ground and separated by 120 degrees.  I simply took a hand drill and free handed this as close as I could.  It could have been much closer, but even free hand I was able to create a usable tripod.  The tripod legs are of different sizes.  The shortest leg is in the lowest hole, the longest leg in the top  hole, etc.   The most difficult thing might be devising a method of attaching the resonator to the copper pipe.  I had the old hustler mast available and it was in poor shape so I didn't mind destroying it.  I cut the threaded tip off of it along with an inch or two of the mast.  I slid the mast in my copper and it fit fairly snugly.  I drilled a hole through the copper and into the mast and put a small metal screw in.  I then used a grinder to smooth the screw head nearly even with the copper pipe.  The PVC pipe has a pipe cap glued on one end.  The other end has a 3/4" threaded fitting glued on and a 3/4" threaded cap on top of that.  

The next sketch to the left is what the whole thing looks like when put away for hiking.  The overall height of the PVC is 77 1/2 inches, a little oversized for a walking stick.  The first step for packing it up is to put all six nuts (threaded rod nuts) on to one of the rods.  The nuts are just a bit too large to slide into the copper.  This is ok because  the three rods are too long to all fit entirely into the pipe.  slide the two rods without nuts into the copper pipe.  Also, slide the stinger from the resonator into the copper pipe.  Now the 3rd rod will slide partially in.   Now slide the copper pipe into the PVC pipe.  You should still have enough room to slide the base of the resonator into the PVC on top of the copper.  Screw in the PVC cap and you're ready to hike!  

Here is the parts list: