(c) 2020 DX Commander Limited - Page 5
FOLDING BACK INSULATED WIRE
The last thing I wanted to mention is the topic of how much folding back elements on themselves has an
affect on the tune of an element.
I have made some preliminary tests and although we are schooled by our teachers to fold back wire on itself
to decrease the length of an element (say a dipole), I have discovered that the new length becomes a
combination of the actual element length plus a proportion of the fold-back, not all of it.
Upon further investigation, it transpires that nobody has really done the field work to settle this argument.
The portion of the element that is folded back, will have an impact on your tune - but not in a linear fashion.
Actually, my field work is suggesting that every 2.5m of (insulated) wire added back on itself counts as 1m of
real length. I need to make a video about this and show you the maths, Trust me! :)
FIRST-TIME ASSEMBLY
Prepare all your elements as the cut chart and solder / crimp the fork connector.
Reserve circa 12m of wire for mistakes / changes. You can add this amount back to your radials when your
build is complete.
Make up your radials. 4 or 5 radials will fit into one fork connector if required. A proper set of wire-strippers
helps here.
Prepare your hose-clamps and clear plastic tubing as discussed earlier.
Hammer three guy stakes into the ground, 120 degrees apart from where the centre of the mast will end up,
120cms from the centre (4 feet).
Extend the pole in your working area and twist-lock each section very firmly by pulling, twisting and
extending at the same time - and then test-erect by eye. I rest the upright pole on my shoulder after
previously looping the guy cord around each of the guy stakes and tying off. Adjust to suit. When taught,
release one guy point and lay on ground (I prefer a couple of garden chairs!).
Unscrew the bottom of the pole and fit the ground Plate to the thread and re-tighten the base. To get a
precise fit,
“unscrew” the cap anti-clockwise until you hear the click of the threads then it will be safe to start
screwing clockwise.
Slide the circular Radiating Plate over the pole so that it fits snugly at the bottom of the mast, on top of the
plastic moulding. Use a hose clamps to stop it from slipping around. Do not over-tighten.
Slip over another XL hose-clamp and tighten just at the join between section 1 and section 2 (there will be
downward force here from the guy point). Do the same for the next section with the slightly smaller hose-
clamp before slipping over the Guy Point.
Test fit the Upper Spreader (which can act as an optional Upper guy-point for severe weather).
Using the 6mm bolts, washers and wing nuts, fit the elements to the Radiating Plate and thread each vertical
through an appropriate hole in the Spreader Plates.
Once you can judge the element lengths, prepare some shock cord of appropriate length and fit a carabiner
to one end - then clip to the Upper Spreader. For very short elements, you may wish to extend the shock
cord with paracord. You are currently making everything temporary at this point to check element lengths.
Bear with me..
Securing the 40m element: Slightly helically wind the 40m element from
the upper spreader to the top of the pole. This will stop it flapping
around. Slip over the end of the tube 3 sections of tubing, the larger
diameter tubing, a small section of the hose-clamp tubing and also the
6mm (small) tubing. Bring your element up the pole and push it through
all three of the these. Make a small loop in the top and come back down
the inside (again) of all three tubes. For the 6mm top section, I found it
best to remove the tubing from the pole and then arc / curve the last
section to slip it over the top. If you get this right, the element will come
