Gain vs boom length
 

It is said that the gain of a Yagi-Uda is directly dependent on the boom
length. And that there is little difference between a 2 element Yagi and
a 3 element Yagi.

Consider a 2 element beam. What if there is no metallic boom? Does the
boom length then refer to the element spacing? Then does a wider spacing
between the elements mean more gain?

Thanks.

Gain vs boom length
 

In article , says...

It is said that the gain of a Yagi-Uda is directly dependent on the boom
length. And that there is little difference between a 2 element Yagi and
a 3 element Yagi.

Consider a 2 element beam. What if there is no metallic boom? Does the
boom length then refer to the element spacing? Then does a wider spacing
between the elements mean more gain?

Thanks.



There is an optimun spacing for the elements, or numberof elements per
boom length.

What the boom is made of makes no difference in the gain provided it is
taken into account of for the length of the elements.

For wider spacing equal more gain, just think of a 2 meter 2 element
beam. If you space the 2 elements out to 15 feet it will be almost no
difference in just a simple dipole.

Chruscraft made 11 element beams on a boom that was too short. They had
very little gain compaired to what they should have. It would have been
better for them to use about 6 to 8 elements.

Gain vs boom length
 

On 8/25/2019 9:40 AM, Ralph Mowery wrote:
In article , says...

It is said that the gain of a Yagi-Uda is directly dependent on the boom
length. And that there is little difference between a 2 element Yagi and
a 3 element Yagi.

Consider a 2 element beam. What if there is no metallic boom? Does the
boom length then refer to the element spacing? Then does a wider spacing
between the elements mean more gain?

Thanks.



There is an optimun spacing for the elements, or numberof elements per
boom length.

What the boom is made of makes no difference in the gain provided it is
taken into account of for the length of the elements.

For wider spacing equal more gain, just think of a 2 meter 2 element
beam. If you space the 2 elements out to 15 feet it will be almost no
difference in just a simple dipole.

Chruscraft made 11 element beams on a boom that was too short. They had
very little gain compaired to what they should have. It would have been
better for them to use about 6 to 8 elements.

Thanks, Ralph. All you say makes perfect sense to me.

So, rather than boom length we should talk about proper element spacing
between elements?

Gain vs boom length
 

On 8/25/2019 2:56 PM, John S wrote:
On 8/25/2019 9:40 AM, Ralph Mowery wrote:
In article , says...

It is said that the gain of a Yagi-Uda is directly dependent on the boom
length. And that there is little difference between a 2 element Yagi and
a 3 element Yagi.

Consider a 2 element beam. What if there is no metallic boom? Does the
boom length then refer to the element spacing? Then does a wider spacing
between the elements mean more gain?

Thanks.



There is an optimun spacing for the elements, or numberof elements per
boom length.

What the boom is made of makes no difference in the gain provided it is
taken into account of for the length of the elements.

For wider spacing equal more gain, just think of a 2 meter 2 element
beam.Â* If you space the 2 elements out to 15 feet it will be almost no
difference in just a simple dipole.

Chruscraft made 11 element beams on a boom that was too short.Â* They had
very little gain compaired to what they should have.Â* It would have been
better for them to use about 6 to 8 elements.

Thanks, Ralph. All you say makes perfect sense to me.

So, rather than boom length we should talk about proper element spacing
between elements?


Oops! That was worded badly. I should have written:

So, rather than boom length we should talk about proper spacing between
elements?

Gain vs boom length
 

On Sun, 25 Aug 2019 14:59:51 -0500, John S wrote:
On 8/25/2019 2:56 PM, John S wrote:
On 8/25/2019 9:40 AM, Ralph Mowery wrote:
In article , says...

It is said that the gain of a Yagi-Uda is directly dependent on the boom
length. And that there is little difference between a 2 element Yagi and
a 3 element Yagi.

Consider a 2 element beam. What if there is no metallic boom? Does the
boom length then refer to the element spacing? Then does a wider spacing
between the elements mean more gain?

There is an optimun spacing for the elements, or numberof elements per
boom length.

What the boom is made of makes no difference in the gain provided it is
taken into account of for the length of the elements.

For wider spacing equal more gain, just think of a 2 meter 2 element
beam.Â* If you space the 2 elements out to 15 feet it will be almost no
difference in just a simple dipole.

Chruscraft made 11 element beams on a boom that was too short.Â* They had
very little gain compaired to what they should have.Â* It would have been
better for them to use about 6 to 8 elements.

Thanks, Ralph. All you say makes perfect sense to me.

So, rather than boom length we should talk about proper element spacing
between elements?

Oops! That was worded badly. I should have written:

So, rather than boom length we should talk about proper spacing between
elements?

... _optimum_ spacing ...

Web search for "eznec".

73
Jonesy
--
Marvin L Jones | W3DHJ | W3DHJ | https://W3DHJ.net/
Pueblo, Colorado | @ | Jonesy | __ linux FreeBSD
38.238N 104.547W | jonz.net | DM78rf | 73 SKi

Gain vs boom length
 

In article , says...


Oops! That was worded badly. I should have written:

So, rather than boom length we should talk about proper spacing between
elements?



As I said, for a given boom length there is an optimum number of
elements. Other factors come into play as to how clean you want the
patern to be.

You can design for several things such as maximum gain, cleanest patern,
maybe others for a given boom length. ? Doubtful that they will all come
together.

As a general rule you get about 3 db every time you double the boom
length. Sooner or later you will reach the point of not being worth it.
Such as a 40 foot boom for 2 meters.