I have always disbelieved the "bond the crossing radials" old wives tail, for
good electrical reasons... These crossing radials have differing RF phase and
voltage on them... Bonding them together is a short circuit causing a lump in
the radial field pattern...
Case in point:
About 10 years ago I had a 4 element, 160 array with 8 elevated radials under
each vertical - the array was parasitic not an all driven... Of course the
elevated radials crossed each other but they were separated by a foot or so...
It is a windy and wild night during CQ160, -10F at 3AM, and Dave needs to take
a whiz... He is back inside within 5 seconds...
'That was a fast whiz', I commented, 'did it freeze and fall off?'...
His lips were moving and he was pointing upwards frantically, but nothing was
coming out... Finally he managed to stammer, "Fire!"
Of course, I instantly bolted for the door... Outside it was black and wild
with the trees waving frantically... No fire to be seen...
I look at Dave... It was a ball of fire right there, he says emphatically (he
is standing back about 25 feet and won't come any closer)...
Then it happened... The rig was on auto CQ with TRLOG happily running the
transmitter... The radial wires were whipping up and down and the radial off
the driven element touched the radial off the reflector just as the amp was
keyed... A ball of fire and a spray of molten copper resulted - right on my
upturned face... Now remember, the reflector is all elevated, it is not
grounded in any fashion... So, the arc of RF/electrons was strictly by way of
induced EMF causing phase and voltage differences on the radials... You cannot
convince me that short circuiting crossing radials is doing anything good for
your pattern...
After we got a rope over the offending radial and controlled it's flapping we
went back inside to thaw out... The story was Dave just got out there,
unzipped, and was letting off the first bit of pressure from an overdistended
bladder when Ghod showed his displeasure with a ball of fire and hot sparks
right down the back of his neck (he was standing directly under the arc)... He
says he got religion right then and there...
I figure since Ghod dislikes bonding radials, who am I to argue...
For the rest of the contest Dave insisted on walking all the way through the
woods to the house to take a whiz...
denny
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