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boomerbubba
join:2001-06-15
Austin, TX

1 recommendation

boomerbubba

Member

These Ducks Quack !!!

I built these reflectors for the stock Rubber Duck antennas on my Linksys BEFW11S4. After fooling around with my own designs, I found that Michael Erskine had already produced an excellent template, so I used his. »osiris.urbanna.net/anten ··· emplate/ Thanks

The twin reflectors are parabolic in only two dimensions, so they are relatively easy to shape. Michael produced the generalized template, but materials and design are left up to the implementor. I used thin-gauge sheet aluminum in 6-inch squares, a balsa center and epoxy.

The twin reflectors preserve and enhance the "diversity" logic of the Linksys twin antennas. And between the rotation of the reflectors and the tilting of the Rubber Ducks they sit on, there is ample flexibility to use the combination to handle many indoor radiation problems.

I have tested the resulting design using the ORiNOCO client Link Test utility, and the results were very pleasing. I didn't have an open space to do a simple test, so I just measured on-site. In my real-world test, including a couple of walls, windows and blinds to introduce plenty of multipath, the reflectors added 8-10 dB to the Rubber Duck dipoles, for an overall gain of 10-12 dBi! These results are consitent with those predicted on Michael's website.

ikarus1
Premium Member
join:2002-10-23
Urbanna, VA

ikarus1

Premium Member

That is sweet. May I copy the picture for the web site?

-m-

boomerbubba
join:2001-06-15
Austin, TX

boomerbubba

Member

said by ikarus1:
May I copy the picture for the web site?

Feel free. It's the least I could do.
NUT7
join:2002-05-12
Norman, OK

NUT7

Member

That is amazing. Talk about modding out a router. Very nice boomer.

stimulation
join:2003-01-13
Argyle, TX

stimulation

Member

very nice.

can you provide step by step instructions?

boomerbubba
join:2001-06-15
Austin, TX

boomerbubba

Member

The vital instructions are contained within Michael's site (linked above).

The construction steps I followed:

•Sized the .jpg template file in MS Paint and Word so that it printed out at the scale I wanted.
•Printed out several copies of the template.
•Squared out the balsa blocks to the exterior lines of the template.
•Glued a copy of the template top-and-bottom to the blocks.
•Rough-cut the balsa blocks to be just larger than the template curve.
•Freehand-sanded the block to fit the curve. I used a stationary belt sander and moved the pieces by hand.
•Cut the thin aluminum sheet to squares.
•Formed the aluminum into curves. (This is the second-hardest part.)
•Drilled holes the right size and depth to insert the rubber ducks.
•Epoxied the curved metal pieces to the balsa forms. I used packing tape and light clamps to hold them in place. (This was the hardest part. If I were doing it again I would first make some kind of a clamping jig first.)
•Painted.
•Gloated.

kb6183
Oh The Corruption
Premium Member
join:2000-09-27
Virginia Beach, VA

kb6183 to boomerbubba

Premium Member

to boomerbubba
No pictures yet, but I just made a couple of these for my 614+ using cardboard, tinfoil, and a glue gun. They aren't pretty and are only 12cm-side squares, but for no real cost and a small amount of time I'm sitting in a former dead zone posting this
kb6183

kb6183

Premium Member

OK, I took a couple of snaps. Not great quality, but you get the picture pun intended

I was going for small size because I'm already in trouble for putting the AP somewhere it doesn't belong

nelsong
join:2001-11-03
Lafayette, LA

nelsong

Member

Thanks a lot guys, this solved my downstairs problem, and didn't cost me a cent!

dandeman
MVM
join:2001-12-05
Chapel Hill, NC

dandeman to boomerbubba

MVM

to boomerbubba
My basement machine needed a little help getting the signal two floors up to the wireless AP.

The reflector shown here was "tuned" while watching the signal strength meter. Helps the crappy little patch antenna on the PC card sticking out the back of the machine do it's thing! Fairly significant improvement is signal strength..

Rygel
Premium Member
join:2001-11-17
Moira, NY

Rygel to kb6183

Premium Member

to kb6183
Nice lunchbox.

Stubert
join:2002-03-27
Des Moines, IA

Stubert to kb6183

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to kb6183
said by kb6183:
I'm already in trouble for putting the AP somewhere it doesn't belong

I'm sure the card-board and aluminum foil helps...

HEE HEE HEE just kidding

That is pretty sweet! I should try that. Does the signal send only in the direction of the reflectors now? or- does it still broadcast everywhich angle?

kb6183
Oh The Corruption
Premium Member
join:2000-09-27
Virginia Beach, VA

kb6183

Premium Member

Looking at the pics on boomer's original link : »osiris.urbanna.net/anten ··· emplate/ using these should make the beam more directional. The canted one is pointing close to directly (by eyeball gauge)at the downstairs room I needed better coverage in. I haven't tried the only other room I really use the notebook in (upstairs bedroom) yet, but it's in the same general direction anyway so I think it will be OK.

Yeah Rygel, the lunchbox is one of the many Pooh items my wife has collected over the years. Makes her happy

When I told her how much money I saved by not having to buy commercial antennas, she figured she could live with them as long as they stay in that spare room!

Thin1
Premium Member
join:2001-09-29
Wallingford, CT

Thin1

Premium Member

If you put enough pooh stickers on your AP and reflectors it might become acceptable anywhere you want it

kb6183
Oh The Corruption
Premium Member
join:2000-09-27
Virginia Beach, VA

kb6183

Premium Member

said by Thin1:
If you put enough pooh stickers on your AP and reflectors it might become acceptable anywhere you want it

LOL I'll keep that in mind

ikarus1
Premium Member
join:2002-10-23
Urbanna, VA

ikarus1 to boomerbubba

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to boomerbubba
There have been quite a few people reporting in and sending pictures. Since this thread seems dedicated to that:

»osiris.urbanna.net/anten ··· /gallery

Here are some pics (some already seen here, some not yet seen).

Thanks again Texas.

-m-

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

Member

to boomerbubba
Yes, I did for the second one, and it worked quite well.

The first one was .... well.... not good.

BBACIS
Premium Member
join:2002-11-23
Hope Mills, NC

BBACIS to boomerbubba

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to boomerbubba
This is getting pretty ghettofabulous

ikarus1
Premium Member
join:2002-10-23
Urbanna, VA

3 recommendations

ikarus1 to stimulation

Premium Member

to stimulation
I have to hand it to you stimulation, you are honest with yourself.

You make me smile and frustrate me at the same time. I raised two sons and a daughter. I think understand you. I could be wrong, but I have you pegged as a young man who knows what he wants and isn't about to let anyone get in his way. When I was your age, I was much the same. Now I am an old man and I just don't hardly give a &$^t, but that is my problem.

If you have a problem (and we all do) it is that you are so confident in your abilities that you fail to realize that every persons efforts are built largely upon the efforts of people who came before them. That antenna design is just something that was generated from the studies that other people did to explain how parabolic antennas worked. The genius was Maxwel and Morse and not even the people that wrote the information on how parabolics worked. The moron who drew a little curve on a piece of paper and told you, "make it this way" only told you that because someone else told him that. On the other hand, that moron, did read a few thousand pages of documentation about antennas to get to the point where he could begin (begin mind you) to understand what is happening with that funny little curve. Here is a link to his personal web page:

»osiris.urbanna.net

Your problem, if you have one (and we all do), is that you think you can deviate from the learning process and jump straight into genius. You can't do that. You have to have mentors, tutors, and teachers. Sometimes they will bore you, most of mine did. But every now and then you will find one like my Calculus professor at University of Texas. That old fart came to class in overalls and a T-Shirt. He walked into the room on the first day and asked if anyone was interested in being able to figure out how much water was in a mud puddle... I was hooked. Bottom line is when you find someone who doesn't bore you, LISTEN to them. Most of us old folks don't like repeating ourselves, we figure if you make us do that you don't respect our opinion. Why would we bother? It frustrates us and bores you.

Your first design was a corner reflector. Now if you find the spot between the arms of that corner reflector where the dipole is precisely 1.25 inchs from the very corner and dead center of the arms, you'll have a pretty good reflector. So you see your first effort wasn't really bad, you just didn't know how to use it. Make the arms longer and it works better. Here's a link to a similar (but smaller) design of my own. Look at the "minicorner":

»osiris.urbanna.net/anten ··· dex.html

Well, while I have you, let me tell you about evesdropping because that is what a keylogger is... I spent a good part of my life evesdropping, it was my job you see. It feels really powerfull to know things about people that they don't know you know, but in the end it can make you very sad. There are things which you REALLY don't want to know. A President once said, "Gentlemen do not read each other's mail." In the context in which he said it, he was being naieve. Gentlemen don't, but nations do.

Here is the best piece of advice I can give you, something that will help you the rest of your life, but you are going to think it is stupid. So just mark it down and think of it from time to time, my father used to say it to me after he got back from Viet-Nam (the second time), "While the apple is on the tree it grows and becomes sweeter, when it decides it is ripe, it falls from the tree and begins to rot." It took me a long time to figure that one out.


Peace little brother.
-m-

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

Member

to boomerbubba
I thank you for that post ikarus. Although a tad bit verbose, thank you. It helped.

I am not spying on anything with the keylogger. I am the only one using this computer. It is just that if I type something very long (an essay, post, long email), and something happens, the keylogger logs in realtime and I never lose anything.

It is quite useful.

Thanks for your help buddy.

ikarus1
Premium Member
join:2002-10-23
Urbanna, VA

ikarus1

Premium Member

Thank you for the reassurance, my faith is restored.

Onward to better things. You have motivated me to
design a reflector based upon a corner design.

Might take a couple of days but I am already working on
it.

-m-
russotto
join:2000-10-05
West Orange, NJ

russotto to boomerbubba

Member

to boomerbubba
I tried it with a Coke can, cut up, with cardboard bracing. No improvement. But then I probably did a lousy job of shaping it.

ikarus1
Premium Member
join:2002-10-23
Urbanna, VA

ikarus1

Premium Member

There are a number of ways that you can have problems with that parabolic template.

You *MUST* get two things very precise. You have to have the curve shaped pretty much exactly like the one you downloaded and you pretty much have to get the antenna in the exact right spot.

Now if you are using a WET-11 or similar hardware, you will want the other template. The diplole template pretty much doesn't work with the WET-11.

If I can help you, mail me off list. Just hit the mail address on the site you got the design from.

-m-

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

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to boomerbubba
A corner reflector would be very good, if you only needed ONE computer to be covered, and it was positioned directly at it.

boomerbubba
join:2001-06-15
Austin, TX

boomerbubba

Member

IIRC from my own research (I investigated corner reflector designs but chose the parabolic design instead) the corner reflector is somewhat less directional.

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

Member

to boomerbubba
hmm. How so?

fredsimon
Truly Yours
Premium Member
join:2001-07-02
Ardmore, PA

fredsimon to stimulation

Premium Member

to stimulation
Keep at it, you really make my day. With your enthusiasum you can't loose. I have faith in you. You should save attempt # 1. It is a classic.

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

Member

to boomerbubba
what?

I am just wondering why.

boomerbubba
join:2001-06-15
Austin, TX

boomerbubba to stimulation

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to stimulation
said by stimulation:
hmm. How so?
After my research and some back-of-the envelope modeling, I figured the most I could hope get from a corner reflector around the rubber ducks would be about 10 dBi, and that would be pretty ungainly. The parabolic has better performance. Not rocket science, just math and physics. Even Marconi used one.

FYI, here is some string I gathered on the subject of corner reflectors:

»www.qsl.net/ve3rgw/corner.html

»web.elec.qmw.ac.uk/resea ··· refl.htm

»groups.google.com/groups ··· rv.net#p

stimulation
join:2003-01-13
Argyle, TX

stimulation to boomerbubba

Member

to boomerbubba
interesting!

The research link sorta looks like my corner.