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K4EEZ
02-05-2006, 11:09 PM
Hello
Can anyone help?
I some how acquired a bunch of Aluminum tubing from an incomplete HF Beam (( See pix Below)) and wanted to know the lengths on how to homebrew a 20 meter mono bander 3 element beam

Ref length?

Driver length?

Element length?

Boom length?

And spacing on the boom

How is it best to feed the driver, direct feed?

Gamma match?

If gamma matched how do I construct one? Lengths Etc, Etc

Why?
I have an inverted Vee wire of #14 wire up at 55 Ft, cut for the top part of 75/80 meters and I have the Z100 by LDG Auto tuner that works really well for all bands, I thought about buying an Amp but that would cost a lot more than having fun and constructing and needless to say I would have to upgrade my tuner as the Z100 only handles 125 Watts (Max), in any case and for now, I run Bear foot (100 Watts on the Icom 706 Mk2-G), but need something with some gain on 20 meters as the wire just is not enough “oomph” in it.

So I am looking into other ways to get more 4 less #“oomph” out of home brewing a beam. I think a 20 meter 3 element beam has something like 8dBi, than my wire that has little or no Gain in dBi, if you have any advice, info, please post here or email me

My QRZ info is good
Thank you for the time.
73
K4EEZ

K4EEZ
02-05-2006, 11:15 PM
More pix of beam parts Below, not even sure what this beam is? never had a HF beam before, I have made a few 6 meters and 2 meters and 70Cm beams and some HF wire...

VE2NSM
02-05-2006, 11:56 PM
One thing, If I were you I'd took advantage of the insulator to make a beta or hairpin match, especially if it's a monobander.

Past that, the type of matching you choose is independant of the spacings and lenghts you're gonna use to achieve the gain and F/B you want. A good three elements on 20m has to be at least 20' long, you can find good designs in the antenna handbook I think.

Even if it's a three element for another band, it's easily scalable.

Good luck!

K9STH
02-06-2006, 12:20 AM
Go to the "downloads" section of this site. Then download the YagiMax suite. The YagiMax program itself is very good for designing yagis. Then you can use either the "gamma" or "hairpin" program plugging in information from the YagiMax program to get the dimensions, capacitor value, etc., for the match that you choose.

Whenever I am designing a yagi I definitely use YagiMax and have found that the information given in "gamma" (that is the match that I generally use on HF) are pretty much "right on".

Glen, K9STH

K4EEZ
02-06-2006, 12:23 AM
hi guys just wondering if anyboay has any ideas as to what the heck this beam is, it is very large, and looks like it has a buch of traps/rod arms on it?

even my dog was wondering what it is

anyone know or seen anything like it?
post at will, this is the Q&A of qrz rite?
K4EEZ http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif

KC7UP
02-06-2006, 04:57 AM
The antenna you have is a KLM KT34 . A 4 ele tribander for 10/15/20. A very good antenna I have one in use currently for 26 years and they are potent.
Curt

KC7UP
02-06-2006, 05:00 AM
If you are interested in this antenna, M2 has updates for it. Also I have a extra copy (copy machine) of the manual with all the spec.'s I would give away for postage. If interested contact me via QRZ info.
Curt

K7FE
02-06-2006, 05:13 AM
Curt is right and the KLM KT34 is a very good antenna. Down load the manual and make sure that you have all of the parts. M2 should have any that you are missing.

Here are some web sites of interest.


http://www.m2inc.com/products/klmaddon/upgrade.html

http://www.eham.net/reviews/detail/1415

ftp://bama.sbc.edu/downloads/klm/kt34xa/KT34XA%20Manual.PDF
My references are for the 6 element and your antenna is the four element version, but they should still be helpful.
73,
Terry, K7FE

VE2NSM
02-06-2006, 01:29 PM
Quote[/b] (K9STH @ Feb. 05 2006,20:20)]The YagiMax program itself is very good for designing yagis. Then you can use either the "gamma" or "hairpin" program plugging in information from the YagiMax program to get the dimensions, capacitor value, etc., for the match that you choose.
I dont agree with that Glen.

Yagimax, elnec, AO/YO/TA, ect are very good to SIMULATE antennas, not to design.
If you have no knowledge about how an antenna works and how to design it, this program will be useless for you.
Now it's a very good tool (I use elnec) to simulate and see how the antenna you've designed is going to perform.

K9STH
02-06-2006, 06:26 PM
Technically your statement is generally true. You do have to have some place to start with. However, YagiMax comes with some "typical" antenna designs. Also, you can "plug in" just about any values and then have the program "optimize" the design. This will generate a design of an antenna for use at the frequency you have indicated. Now as to if you want to use this particular design is your choice. However, the program will design an antenna for you.

Now I do recommend reading some reference material such as the older ARRL antenna manuals, various articles in the amateur radio magazines concerning antennas, the RSGB books, and so on to get familar with the dimensions of a typical antenna for the chosen band.

However, at least YagiMax will design an antenna for you, but I don't know about the other programs since I don't use them. I definitely have an idea as to where I need to start with a yagi design for any band that I am wishing to build an antenna. As for someone else, that I cannot control.

Glen, K9STH

WA3KYY
02-06-2006, 06:59 PM
You might try this link for plans on a homebrew 20M 3-el yagi. There are links to other designs as well.

DX Engineering Home Brew 20M Yagi Design (http://www.dxengineering.com/TechArticles.asp?ID={92CA149E-274D-4D83-8974-BDB0D9620585})


But first get the manual for that antenna and see if you can put it together as manufactured.


73,
Mike WA3KYY

VE2NSM
02-06-2006, 07:33 PM
Quote[/b] (K9STH @ Feb. 06 2006,14:26)]However, YagiMax comes with some "typical" antenna designs. Also, you can "plug in" just about any values and then have the program "optimize" the design. This will generate a design of an antenna for use at the frequency you have indicated. Now as to if you want to use this particular design is your choice. However, the program will design an antenna for you.
Glen, K9STH
That I did not know, or remember. I used the program a long long time ago for a brief period of time, then I discovered elnec and I never turned back.
I did not remember it had an optimization feature, the thing that I liked right away about elnec was the possibility to simulate any kind of wire, over any kind of ground, unlike yagimax which allowed only free space and perfect ground, if my memory serves me well.

Although yagimax seems to be more friendly, trigonometry wise http://www.qrz.com/iB_html/non-cgi/emoticons/wink.gif

KL7AJ
02-06-2006, 07:44 PM
Quote[/b] (k4eez @ Feb. 05 2006,17:23)]hi guys just wondering if anyboay has any ideas as to what the heck this beam is, it is very large, and looks like it has a buch of traps/rod arms on it?

even my dog was wondering what it is

anyone know or seen anything like it?
post at will, this is the Q&A of qrz rite?
K4EEZ #http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif
What a clueless dog! http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif How did he ever get his ticket?

Eric

K7FE
02-07-2006, 04:35 AM
Quote[/b] (kl7aj @ Feb. 06 2006,11:44)]
Quote[/b] (k4eez @ Feb. 05 2006,17:23)]hi guys just wondering if anyboay has any ideas as to what the heck this beam is, it is very large, and looks like it has a buch of traps/rod arms on it?

even my dog was wondering what it is

anyone know or seen anything like it?
post at will, this is the Q&A of qrz rite?
K4EEZ http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif
What a clueless dog! http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif How did he ever get his ticket?

Eric
Eric,
Be nice...........He may have a "Golden Receiver" http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

K9STH
02-07-2006, 03:39 PM
FE:

You need to look at the photographs that he has posted. The dog is a German Shepherd.

Glen, K9STH

K4EEZ
02-08-2006, 12:51 AM
Quote[/b] (K9STH @ Feb. 07 2006,03:39)]FE:

You need to look at the photographs that he has posted. #The dog is a German Shepherd.

Glen, K9STH
Hey guys
Funny jokes, my dog is cool, he sits here at night when I am or tuning around the ham bands on the 706, he's a cool dog, but he likes to play a lot of the time

When I am out on the roof playing around with antennas, he is there out in the back yard, funny this is, When bad weather is approaching, weather it be thunder storms way off in the far distance that I cant even hare, or 10 min’s before it rains, he starts to wyne even before the weather gets here at the house,
Now that's what a call a man's best friend

and that is why he was in the yard, he is named after the leed singer in the rock group call Ac/Dc
I thought about giving him a call K4K9 or somthing LOL http://www.qrz.com/iB_html/non-cgi/emoticons/biggrin.gif

We did have two, but we had to put her down, her back legs could no longer support her
It was a very hard time to do that; god only knows what it did to my one and only pup left.
and yes take a look at the photograph, it cool.

Curt,
I have emailed you last night, hope you got the email, if you could please let me know

And to the Group that replied
thank you all for your time, help and interest

De K4EEZ
Mark
http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif

K7FE
02-08-2006, 04:18 AM
Mark,
Your dog should have a "K9" call sign, like K9DOG. http://www.qrz.com/iB_html/non-cgi/emoticons/tounge.gif

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