"J.B. Wood" wrote in
:

The E and H far-field formulas I previously provided give magnitude and
direction of these vectors using spherical coordinates (r, theta, phi)
relative to a Cartesian system. If you don't understand coordinate
systems and vectors then I can see why you might be confused.


I'll admit to that. All I knew was that this loop I saw was a helix,
pointed so the axis of the 'cylinder' would point to the stantion wanted, and
was laid with an open coil on a frame rather than wound like wire on a pully
or other former that would bunch the windings as close as possible. I
imagined that if ether form were pointed not-so-accurately at the right spot,
the helical form might 'blur' the response, weakening it, allowing it to be
more selective of something it WAS accurately pointed at. Other than this, I
don't know why it would be built with this extra spacing per turn, because it
limits easy portability. I assume there is a good reason, I just don't know
it..

On Friday, October 10, 2014 3:06:36 PM UTC-5, Lostgallifreyan wrote:
"J.B. Wood" wrote in

:



The E and H far-field formulas I previously provided give magnitude and

direction of these vectors using spherical coordinates (r, theta, phi)

relative to a Cartesian system. If you don't understand coordinate

systems and vectors then I can see why you might be confused.





I'll admit to that. All I knew was that this loop I saw was a helix,

pointed so the axis of the 'cylinder' would point to the stantion wanted, and

was laid with an open coil on a frame rather than wound like wire on a pully

or other former that would bunch the windings as close as possible. I

imagined that if ether form were pointed not-so-accurately at the right spot,

the helical form might 'blur' the response, weakening it, allowing it to be

more selective of something it WAS accurately pointed at. Other than this, I

don't know why it would be built with this extra spacing per turn, because it

limits easy portability. I assume there is a good reason, I just don't know

it..

I don't think it's really too critical. Solenoid or pancake wound, I
doubt you would notice enough difference to worry about.
Also the wire spacing is not very critical either. Some I've built
with insulated wire, I had the wire tightly wound with no real
spacing.
The insulation adds some spacing, and the wires can't short against
each other due to it.
If I use uninsulated wire, I'll usually have a bit of spacing to
make sure the wires won't touch due to movement, etc. I wind those
pretty taut, so it's not a problem as long as you have a slight space
between the wires even with the bigger loops.
Anyway, do it whatever way you want.. There won't be enough difference
to worry about as long as it's tuned.

wrote in news:5c278193-aade-443c-abfc-
:

Anyway, do it whatever way you want.. There won't be enough difference
to worry about as long as it's tuned.


Ok. That works for me. Incidentally, is there any worth to the idea of
using an intact degaussing coli hoiked from some old CRT? Could it be easy
enough to tune that with small external modification, to make a tuned loop?
They're very durable (usually tightly wrapped with some resinous fabric
tape), easily stowed, and the ability to grab both 'sides', twist half a
turn, lay one bight on to the other to form a doubled loop, might also be
helpful in rapidly coercing one into usefulness.

A tad off-topic for Gareth's intent I know, but it IS a short antenna, if it
works...

On Friday, October 10, 2014 3:06:36 PM UTC-5, Lostgallifreyan wrote:
I

imagined that if ether form were pointed not-so-accurately at the right spot,

the helical form might 'blur' the response, weakening it, allowing it to be

more selective of something it WAS accurately pointed at.

Lack of balance is what will cause problems. It can skew the pattern
a bit, and the nulls won't be as deep. But how you wind the coil
won't effect balance too much as long as everything is symmetrical
and no feedline issues.

wrote in news:c2f6c44c-8f80-4799-88d6-
:

Lack of balance is what will cause problems. It can skew the pattern
a bit, and the nulls won't be as deep. But how you wind the coil
won't effect balance too much as long as everything is symmetrical
and no feedline issues.


Thanks. When I eventually do this it will be with as much accuracy as I can
easily muster. It's one reason I haven't tried it yet. Precision for good
nulls is a point not lost on me, though I usually find it in electronics or
sound synthesis..

That other thing, the kite reel longwire, ended up more awkward too. It's
great, but messing with fibreglass and resin to insuklate the reel and some
other details took more time than I thought. Worth it though, it has a well-
mounted ICE 183A matching transformer on it, and I'll adapt it to a mount
with a few tent poles and a single guy wire. I really like the idea of being
able to install a mile long Bevarage antenna in little more time than it
takes to run said mile. Once I have exhauseted that wheeze I'll try the
loop. Unless winter starts to force my hand first..

That was so off-topic I'll stop right there.