November 2001
Beginner
144 pages
3h 41m
English
Content preview from Building Wireless Community Networks
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The Pringles Can
At the Portland Summit last June, Andrew Clapp presented a novel yagi antenna design. It used a bolt, metal tubing, washers, and PVC tubing to make an inexpensive “shotgun” yagi, either 18” or 36” long. While his antenna shows between 12 and 15dBi gain (which is impressive for such a simple design), it’s also quite large. When we returned from Portland, some members of our local group and I realized that, if we were careful, we could fit a full wavelength inside a Pringles can, as shown in Figure 7-1. This would show a reduced total gain, but it would also make the entire antenna much more compact.
Figure 7-1. The complete antenna—it’s just a can!
Parts List
Here are the items you’ll need to make a Pringles can antenna:
|
Part |
Approximate cost |
|---|---|
|
All-thread, 5 5/8” long, 1/8” OD |
$1.00 |
|
two nylon lock nuts |
$0.10 |
|
five 1” washers, 1/8” ID |
$0.10 |
|
6” aluminum tubing, 1/4” ID |
$0.75 |
|
A connector to match your radio pigtail (we used a female N connector) |
$3.00 |
|
1 1/2” piece of 12-gauge solid copper wire (we used ground wire from house electrical wiring) |
negligible |
|
A tall Pringles can (any flavor, Ridges are optional) |
$1.50 |
|
Scrap plastic disc, 3” across (like another Pringles can lid) |
negligible |
|
TOTAL |
$6.45 |
Of course, buying in bulk helps a lot. You probably won’t be able to find a 6-inch piece of all-thread; buy the standard size (usually one or two feet) and a ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.