I was trying to get some comparative data on quad vs quagi antennas
for a club presentation. I would like to be able to compare Quads of a
given number of elements with Quagis of the same number. It is my
understanding that for short boomed antennas the quad will win out but
the quagi is best for longer higher gain antennas. Some numbers would
really help illustrate this but so far I have not found any
information on short quagis.

Jimmie

On Nov 4, 9:38 pm, JIMMIE wrote:
I was trying to get some comparative data on quad vs quagi antennas
for a club presentation. I would like to be able to compare Quads of a
given number of elements with Quagis of the same number. It is my
understanding that for short boomed antennas the quad will win out but
the quagi is best for longer higher gain antennas. Some numbers would
really help illustrate this but so far I have not found any
information on short quagis.

Jimmie

Jimmie, this is not a flame:
But, you intend to lecture to others and you do not even begin to
understand the subject - do you see a contradiction here?

There is no way this group can turn you into an instant expert by way
of one or two postings to this reflector... The possibilities of you
looking like an idiot in front of your friends are endless - all it
takes is one question from the audience where you try to wing the
answer, then someone points out the holes in your answer, and poof!

My best advice is for you to cancel your lecture and begin a bit of
testing on your own (become an expert)... Two meters is an easy band
to work with... Get a wood handle for a hoe, or some such, and drill
holes... Start with a yagi from the antenna hand book - let me suggest
3 elements to start with, and if you want more gain then go to 5 or 7
elements, i.e. always have an odd number of elements... Measure the
gain and the pattern at 0-45-90-135-180 degrees...
Then change the reflector to a quad element - repeat...
Then the driven, etc...

Then when you give the lecture you will know the material, you will be
able to show them the antenna(s), and your test data... And even if
you didn't get the answers you/they expect, you will be the local
expert...
cheers ... denny / k8do

"Jimmie D" wrote in message
...

"Denny" wrote in message
ups.com...
On Nov 4, 9:38 pm, JIMMIE wrote:
I was trying to get some comparative data on quad vs quagi antennas
for a club presentation. I would like to be able to compare Quads of a
given number of elements with Quagis of the same number. It is my
understanding that for short boomed antennas the quad will win out but
the quagi is best for longer higher gain antennas. Some numbers would
really help illustrate this but so far I have not found any
information on short quagis.

Jimmie

Jimmie, this is not a flame:
But, you intend to lecture to others and you do not even begin to
understand the subject - do you see a contradiction here?

There is no way this group can turn you into an instant expert by way
of one or two postings to this reflector... The possibilities of you
looking like an idiot in front of your friends are endless - all it
takes is one question from the audience where you try to wing the
answer, then someone points out the holes in your answer, and poof!

My best advice is for you to cancel your lecture and begin a bit of
testing on your own (become an expert)... Two meters is an easy band
to work with... Get a wood handle for a hoe, or some such, and drill
holes... Start with a yagi from the antenna hand book - let me suggest
3 elements to start with, and if you want more gain then go to 5 or 7
elements, i.e. always have an odd number of elements... Measure the
gain and the pattern at 0-45-90-135-180 degrees...
Then change the reflector to a quad element - repeat...
Then the driven, etc...

Then when you give the lecture you will know the material, you will be
able to show them the antenna(s), and your test data... And even if
you didn't get the answers you/they expect, you will be the local
expert...
cheers ... denny / k8do

Denny,
First of all I never said I was giving a lecture but I can see how this
could be a logical assumption. I dont need to be an expert or want to be
one. I just said I wanted to collect some data. If I were comparing a quad
to a yagi my task would be no problem. I just cant find any info on a 4 or
5 element quagis. My assumption is that a quad would be the higher gain
antenna when this number of elements are involved. I can understand why
this information would be hard to find but thought that if there is any
place it can be had it is here at RRAA. I have found one reference that
implies that a quagi by definition is 6 elements or more.

Like most hams I have no way of making the measurements you suggest. It
must be nice to live in a world where you would assume I could.

All I really need is data I asked for. If someone aske me a question I
dont know I have a good answer for them, "I dont know". I dont "wing it".

Sincerely
Jimmie

Hi Jimmie

Do you use EZNEC?

Jerry

....[snip]....
testing on your own (become an expert)... Start with a yagi from the
antenna hand book - let me suggest 3 elements to start with, and if you
want more gain then go to 5 or 7 elements, i.e. always have an odd
number of elements...

WHY always an ODD number of elements?

I can understand three: reflector, driven, and director, but I don't
understand NOT four: reflector, driven, 1stDirector, 2ndDirector ???

--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
NRA Life Member & Certified Instructor for Rifle, Pistol, & Home Firearm Safety
Also Certified Instructor for the Kansas Concealed-Carry Handgun (CCH) license

Hi Jimmie

Mt Cebik has some words on this.. I'll admit I didn't read it, only
searched for the word on his site.

http://www.cebik.com/vhf/qy.html

Might be a good place to start.

I note your reluctance to model antennas. This is however a great
technique you can deliver to your club members!

Cheers Bob VK2YQA


JIMMIE wrote:

I was trying to get some comparative data on quad vs quagi antennas
for a club presentation. I would like to be able to compare Quads of a
given number of elements with Quagis of the same number. It is my
understanding that for short boomed antennas the quad will win out but
the quagi is best for longer higher gain antennas. Some numbers would
really help illustrate this but so far I have not found any
information on short quagis.

Jimmie

Hi Jimmie

EZNEC isnt restricted totheoritical antennas. I use it alot to get data
for my real antennas. I can get better information on my antenna designs
with EZNEC than I get with the actual pattern measurement.
I am an old guy with almost no computer skill. But, EZNEC has been very
easy for me to use. I got a good head start from a couple aarr regulars,
so I didnt even need to read the instructions.

Jerry





"Jimmie D" wrote in message
...

"Jerry Martes" wrote in message
newsMKXi.6394$Zz.3256@trnddc07...

"Jimmie D" wrote in message
...

"Denny" wrote in message
ups.com...
On Nov 4, 9:38 pm, JIMMIE wrote:
I was trying to get some comparative data on quad vs quagi antennas
for a club presentation. I would like to be able to compare Quads of a
given number of elements with Quagis of the same number. It is my
understanding that for short boomed antennas the quad will win out but
the quagi is best for longer higher gain antennas. Some numbers would
really help illustrate this but so far I have not found any
information on short quagis.

Jimmie

Jimmie, this is not a flame:
But, you intend to lecture to others and you do not even begin to
understand the subject - do you see a contradiction here?

There is no way this group can turn you into an instant expert by way
of one or two postings to this reflector... The possibilities of you
looking like an idiot in front of your friends are endless - all it
takes is one question from the audience where you try to wing the
answer, then someone points out the holes in your answer, and poof!

My best advice is for you to cancel your lecture and begin a bit of
testing on your own (become an expert)... Two meters is an easy band
to work with... Get a wood handle for a hoe, or some such, and drill
holes... Start with a yagi from the antenna hand book - let me suggest
3 elements to start with, and if you want more gain then go to 5 or 7
elements, i.e. always have an odd number of elements... Measure the
gain and the pattern at 0-45-90-135-180 degrees...
Then change the reflector to a quad element - repeat...
Then the driven, etc...

Then when you give the lecture you will know the material, you will be
able to show them the antenna(s), and your test data... And even if
you didn't get the answers you/they expect, you will be the local
expert...
cheers ... denny / k8do

Denny,
First of all I never said I was giving a lecture but I can see how this
could be a logical assumption. I dont need to be an expert or want to be
one. I just said I wanted to collect some data. If I were comparing a
quad to a yagi my task would be no problem. I just cant find any info on
a 4 or 5 element quagis. My assumption is that a quad would be the
higher gain antenna when this number of elements are involved. I can
understand why this information would be hard to find but thought that
if there is any place it can be had it is here at RRAA. I have found one
reference that implies that a quagi by definition is 6 elements or more.

Like most hams I have no way of making the measurements you suggest. It
must be nice to live in a world where you would assume I could.

All I really need is data I asked for. If someone aske me a question I
dont know I have a good answer for them, "I dont know". I dont "wing
it".

Sincerely
Jimmie

Hi Jimmie

Do you use EZNEC?

Jerry





Sorry, I have always been afraid if I get a program like that I will sit
around to much designing theoretical antennas.
I can see how it could become addictive.

Jimmie

"Jimmie D" wrote in message
...

"Jerry Martes" wrote in message
news:HpNXi.9904$9N6.7941@trnddc03...
Hi Jimmie

EZNEC isnt restricted totheoritical antennas. I use it alot to get
data for my real antennas. I can get better information on my antenna
designs with EZNEC than I get with the actual pattern measurement.
I am an old guy with almost no computer skill. But, EZNEC has been
very easy for me to use. I got a good head start from a couple aarr
regulars, so I didnt even need to read the instructions.

Jerry


But I would run a lot of theoretical antennas if I had it. I can see me
wasting a lot of time with it.
Granted it would be great for he project I am trying to do now and I am
sure its a great product.

Jimmie

Hi Jimmie

Forgive me if I sound flippant. But, this "computer modeling tool" isnt
intended to be a time wasting device. There is no reason to think of it
as just a "theoretical" program. EZNEC shows you quickly what your
antennas can be expected to do in Real Life. I consider EZNEC to be one of
the finest electronic/antenna tools a person can buy. And, if finances
are tight at this time, Roy is willing to let you use the program without
any money trading hands. The program would be an excellent way for you to
gain the confidence you are looking for when discussing Antennas with your
associates.
My advice to continues to be "try it, you'll like it".

Jerry

I have spent about 4 months on 2m antenna test range playing with Yagi -
Quad - Razor (Quagi) designs. (before modeling software was available)
Design objectives were to obtain best gain, F/B - clean pattern aand 50 ohm
impedance.

My findings we

The maximum performance for 3 el. antenna was obtained from 3 el Quad.
The rule seems to be quad elements work best with one on the front and one
behind the driven quad element or log cell.

For 4 el. parasitic antenna it was 3 Q and 1 Y element.

For 5 and 6 el it was 3 Q 2 (3) Y

For 7 el the winning combination was Y refl. Q refl. 2Q log driven cell, Q
dir. 2x Y dir.

For over 7 el. I would just keep adding Yagi directors.

See http://www.k3bu.us/razor_beams.htm for some pictures on the cover CQ
Magazine featuring stacked 15 m 7 el Razors.

Hope it helps.

73 Yuri, K3BU, VE3BMV