Hardware Hacking Projects for Geeks

45

3

3. How to Hack

802.11b Antennas

Cost

Time

Difficulty

$10–20

a few hours

easy

I’ve been using a wireless Ethernet card in my laptop for several years. The

change from wired networking to wireless was an amazing shift. I was no

longer tethered to a thick cable. I could wander around my office or my

home and connect to the Web. However, in many situations I found that

the range of the built-in antenna in the PC card was limited, and I desired

additional range.

In this hack, I will show you how to build two different range-extending

antennas for your wireless LAN card. The first design is made from a used

soup or coffee can. It is inexpensive and easy to implement, and will send

and receive a signal in one direction that’s up to 16 times more powerful

than the built-in antenna on your wireless card. The second design uses a

discarded Primestar satellite TV dish antenna. It is highly directional and

can theoretically send and receive data to another dish up to 10 kilometers

away under ideal conditions.

Credits

All photographs (except Figure 3-4) copyright

© 2003 Rob Frohne.

What You Need

• 802.11b network card

• Computer (Windows, Linux, Mac)

• A Primestar dish

• Soldering iron

• N-style RF connector

• A chassis-mount N connector

• Low-loss coaxial cable (optional)

• A “pigtail” connector

• Other items listed in

Exhibits A and B

ch03_antennas.indd 45

1/21/2002 12:25:40 PM