SpiderBeam
 

On Feb 8, 10:40 pm, Tom Horne wrote:
Brian
You have my undivided attention on this one. Can you steer me to a
design for the Cubical Quad that you were referring to?

Oops. There's some confusion here but I don't know which one of us is
confused Tom. Maybe both of us. I wasn't referring to a specific quad.
My point was that any properly tuned unnamed generic quad should be a
better-performing antenna than a Spiderbeam. However the usual HF quad
is not a lightweight antenna, they're designed/built to take a beating
out in the weather for the long run and as you know fiberglass ain't
feathers.

However for applications like dxpeditions, Field Day and other
temporary locations where weight matters one should be able to design/
build a very lightweight quad by using small diameter spreaders which
would not be acceptable for use in permanent antennas. If done right a
"portable quad" ought to be able to compete with the Spiderbeam as far
as weight is concerned.

QSL?

Miles and miles of spreaders:

http://www.mgs4u.com/fiberglass-tube-rod.htm

Brian w3rv

SpiderBeam
 

Brian Kelly wrote:
On Feb 8, 10:40 pm, Tom Horne wrote:
Brian
You have my undivided attention on this one. Can you steer me to a
design for the Cubical Quad that you were referring to?

Oops. There's some confusion here but I don't know which one of us is
confused Tom. Maybe both of us. I wasn't referring to a specific quad.
My point was that any properly tuned unnamed generic quad should be a
better-performing antenna than a Spiderbeam. However the usual HF quad
is not a lightweight antenna, they're designed/built to take a beating
out in the weather for the long run and as you know fiberglass ain't
feathers.

However for applications like dxpeditions, Field Day and other
temporary locations where weight matters one should be able to design/
build a very lightweight quad by using small diameter spreaders which
would not be acceptable for use in permanent antennas. If done right a
"portable quad" ought to be able to compete with the Spiderbeam as far
as weight is concerned.

QSL?

Miles and miles of spreaders:

http://www.mgs4u.com/fiberglass-tube-rod.htm

Brian w3rv

Brian
I'm afraid that I'm the one that was confused I was hoping that you had
a specific design in mind. I have all of the parts for the one that was
on the site of the clean off that I got a forty two foot tower from but
I got it disassembled. It just needs a plan for reassembly. I guess I
will have to ask around at the club and find an antenna Elmer that would
be willing to help with guiding the reassembly so that we can test it
well before field day. I've forgotten so much in the thirty years I
have been out of Radio that it is almost like starting over.

Thank you very much for that link. I'm sure that will come in mighty
handy as field day plans go forward.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison

SpiderBeam
 

My point was that any properly tuned unnamed generic quad should be a
better-performing antenna than a Spiderbeam. However the usual HF quad


free space NEC calculations for both:

Spiderbeam (from www.spiderbeam.net)

20: 6.7 dBi gain
15: 6.9 dBi gain
10: 7.1 dBi gain

full-size 2 el quad (from www.cebik.com)

6.8-7.2 dBi (at freq where f/B is peak, also depends on boom length)

I'd say in practice they are pretty much equal...the quad being three-
dimensional will be much harder for one or two people person to put up.

Tor
N4OGW

SpiderBeam
 

I'd say in practice they are pretty much equal...the quad being three-
dimensional will be much harder for one or two people to put up.

Tor
N4OGW

SpiderBeam
 

wrote:

My point was that any properly tuned unnamed generic quad should be a
better-performing antenna than a Spiderbeam. However the usual HF quad



free space NEC calculations for both:

Spiderbeam (from www.spiderbeam.net)

20: 6.7 dBi gain
15: 6.9 dBi gain
10: 7.1 dBi gain

full-size 2 el quad (from www.cebik.com)

6.8-7.2 dBi (at freq where f/B is peak, also depends on boom length)

I'd say in practice they are pretty much equal...the quad being three-
dimensional will be much harder for one or two people person to put up.

Tor
N4OGW

I would further speculate that the odds of the "as deployed" performance
(in a temporary portable/field erection) of the quad being what the
model says are lower than for the Spiderbeam. The quad is bulkier and
3D, and deformations and environmental effects might be more of an issue.



Jim, W6RMK