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New Yagi Plans including exact measurements
I was given an old Aironet 15dbi Yagi antenna. I took it apart, measured it with Vernier Calipers, and put up a small webpage. This one is quite simple. It uses small metal rods for elements, a loop for the driven element, and the whole thing is based on a plastic dowel, which could easily be substitued with a wood dowel, a piece of conduit, or even a just a wood stick similar to the ["MicroTVAerial"].
My webpage for it is http://www.andrewhakman.dhs.org/yagi. Hope it's usefull.
Another example of cheap 8dB yagi you can make with PVC pipe and misc parts.
Broken link -> http://wiki.truffula.net/ashlandwifi/index.php/PvcYagi
"An interested reader added this:
Here is a site that did a "802.11b Homebrew Antenna Shootout". The author tests an improved omni, a pringles yagi, and a couple of waveguide antennas. He found a simple tin can waveguide antenna beat the pringles yagi by almost 9db. http://www.turnpoint.net/wireless/has.html. Another [http://www.waterloowireless.org/events/WWShootout_debrief.html shoot-out] at [http://www.waterloowireless.org/ WaterlooWireless]
Here is what I came up with from the txt file. Visit PEWUG for more info.
I have looked at alot of different designs of yagi antenna's and one question I have that maybe someone could clear up is this; On the yagi's with the elements, like the one's with metal rods inserted into plastic, there is no metal connection between the elements as they are shielded by the plastic rod, so why on the bazooka/pringles type antenna are people using metal rods with metal washers/elements that contact the metal rod? I am no antennae designer, but it would seem to me that if it works for the other type of yagi that it would work well for this bazooka/pringles type antenna as well. I am sure you could use a plastic rod instead of a metal one and use plastic spacers as well. This would seperate all the metal washers without a metal/electrical connection between them just like the other yagi design. All in all I guess I need to put my money where my mouth is and try it out. But just a thought that maybe someone could try. If you beat me to the punch and it works/doesn't let me know. TDave00@yahoo.com
- (Switching a design from a non-conducting boom to a conducting (metal) boom may require some slight adjustment to the length of the elements in order to compensate. At lower frequencies (VHF, HF) boom composition has little effect because the elements are mounted at the center which is a low voltage/current point on the element. Stick to a particular plan and you'll be OK, otherwise you may have to fiddle around to compensate.)
I think alot of people out there would love to see some more detailed instructions of the bazooka type antenna. The txt file does not really give a clear example of how to build it. A few questions I had were.. referring to txt file http://seattlewireless.net/docs/antenna.txt
- Are the spacers 8 - 15 = 1.745?
- The spacers were cut to 1.75 inches.
- The turquoise tube were did you get it from?
- More readily available than that tubing is standard PVC pipe.
- What is the length of the housing for the antenna?
- The overall length of the housing was 32" but that is not critical. The critical factor is the distance of the end of the element to the brass tube extension on the N Connector(1"). This is adjusted by moving the all-thread in the center of the electrode up or down using the nuts on either end for adjustment.
- What is length of the brass tube affixed to the inside of the cup, is it 1.04?
- You will need to cut a piece of 5/32 brass tube to fit over the center of the electrode on the N-connector-crimped slightly The length of the brass tube depends upon the diameter of the casing enclosure...cut it to whatever length will center the end inside the enclosure...roughly 1" for 3"PVC and 1 1/2" for 4" PVC
- The metal cup, what is it made from, is it something we can get at a hardware store.
- No, you can use dryer hose connectors which come in either 3" or 4" sizes...just test for fit in whatever pvc you use. For the base reflector you can cut the bottom out of whatever can will fit tightly in a 3" or 4" base or cut your reflector from thin galvinized sheeting (ie. rolled roof flashing, galvanized sheeting, etc;just check for conductivity on roof flashing as it is sometimes coated...or just sand it on the edges where it will contact the dryer connector insert to be safe) The other critical dimension is the distance of the center electrode from the reflector base which was 1 3/4 " in this case.
- On the bolt, does it go nut, plastic disc, washer, spacer, washer, etc, or nut, plastic disc, spacer, washer, spacer, etc.
- On the bottom it was nut, plastic disc, spacer...on the top nut, plastic disc, washer, spacer. The dimensions used(length of spacers, diameter of washers) used in this antenna were specific to the overall length and number of elements. That is, in shorter yagis such as the pringles can and a few others mentioned you need to reduce the length of the spacers(1.2") and the diameter of the washers(1"). Note that in the other designs there is no initial difference in the size of the first two spacers. The primary consideration in our experiment with antennas was that a variety of reflectors worked to some degree... whether we were just punching holes in the side of cardboard containers with metal bottoms or just using flat reflector plates...they all worked. If your just trying to shoot down the street point to point just about any of the contraptions on this page will work. Just buy your self a simple N connector and a little extension tubing for the electrode and have a good time. Ben Sanders
I anyone has more detailed instructions please email them to me at firstname.lastname@example.org Thanks.
Here are some of our efforts, more documentation and parts list coming soon once we get a nice design for the enclosure that can be mounted outdoors.
If you can't wait for our docs, there is another effort underway in Portland at
Rob flickenger has a nice variation on this that fits completely in a pringles can.
Here's a pretty cool video of a pringles can antenna.
In the meantime, check http://seattlewireless.net/images/BuildingYagi/photo_index.html for pictures of an inexpensive and attractive yagi suitable for mounting outdoors by BenSanders.
Here http://6mt.com/2304tech.htm is a bunch of 13cm band ham radio antennas. They only need to be scaled down slightly in size for our use.
line of sight
Test with commercial DirectionalYagi. 3 millisecond ping, good signal.
Test with LucentYagi 3 millisecond ping, good signal.
which is homemade?
prototype yagi with commercial reflector. 3 millisecond ping.
spicy 8 can? nope. this will not work.
tuna can? this doesn't work either.
3 inch square aluminum? Intermittent (in a bad way) 3-12 millisecond pings. seriously impossible to mount to the PVC reliably.
Trader Joe's English Breakfast Tea full of ez-foil pie tin? 3 millisecond ping. We aren't going to try and mount this but we've learned a bit about the correct size and needs of the reflector. We are trying to find an easily available item for the parts list. Once we find it, we will have a list of parts to make this antenna for roughly $25 of hardware store (and maybe supermarket) parts.
on a totally unrelated note... what model of picturebook is that? mine has a totally different hinge. --ForrestEnglish
- I've put my aluminum tube antenna on hold for now. I loaned my BEFW11S4 to a friend who needed it for a short period of time. I'm doing some experiments with fiber right now but will try to keep lurking the site to keep up to speed.
Using a surplus Ku-band DSS dish: