New design (5 places)


Old design  (2 places)


Old design  (3 places)


1/2" Copper


1/2" PVC


Split
1/2" PVC Tee



3/4" Copper


1/2" Copper


After several years of harsh UV sunlight, the nylon cable ties (ty-wraps) holding the stand-off insulators will begin to break.  v2.0 eliminates the ty-wraps, modifies the stand-offs, and makes a much sturdier structure.. Fig 1 and Fig 2 shows the original design, and Fig 3 the new design. 

Begin by gluing the two Tees and a short piece of PVC pipe together.  Cut the PVC pipe length , so that when made-up,  the copper elements are spaced 7" (center-to-center).  For best alignment, temporarily stick a piece of PVC pipe into the running end of each Tee, then glue and assembling on a flat work bench.  

On the 1/2" copper tubing side of the stand-offs, glue and insert short pieces of 1/2" PVC pipe into the Tees, as shown in Fig 4.  Then saw them in half.  A band saw works best.   Join the split Tee around the copper tubing and secure with a hose clamp.

On the 3/4" copper tubing side, saw tees in half discarding the smaller pieces.   Then fabricate saddles made form split 1/2" PVC pipe, as shown in Fig 3.  These parts distort somewhat (ovally) when clamped, so be sure to have glued the Tees first.

It is best to not fully tighten the hose clamps until everything is laid out on a flat surface 

If you have already built this antenna you will only need to replace three stand-offs with the new design.  The standoffs in Fig 2 will stay.

A word about installation: Observe all safety precautions discussed in the first chapter of the ARRL Antenna Book.  Get a helper. This thing is pretty flimsy until it is vertical and guyed at 3/4 up, then it is quite stout and wind resistant. 




Fig 1
Fig 2
Fig 3
Fig 4
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