Trying to use what I had at hand, I put together a quick cantenna and ran some tests. I'm describing the results here hoping that I can get ideas for improvement. I built the cantenna following the instructions at:
I attached the cantenna to the WMP11 and used Netstumbler to make some measurements. The overall results were disappointing. The cantenna didn't give me any improvement over the original rubber ducky antenna that came with the card. I was able to see drops in the signal level of up to about 20 dB depending on where I pointed the cantenna, but even when pointed in the optimum direction the level was about equal to level with the card's original omni antenna.
Thinking that I might be losing a lot of signal in the coax and connectors, I shortened the cable from 5 feet to 1 foot and eliminated
2 of the connectors. But that made no difference. That surprised me. Doesn't that imply that the problem is elsewhere? I know I should get some LMR cable and the right connectors, but I wonder if it will make a difference since shortening the lossy cable and removing connectors didn't help.I also tried changing the length of the cantenna from 6 inches to 12 inches by adding a second can but that made very little difference (about 1 or 2 dB).
Another thing I noticed is that, without any modifications, a usb dongle I had on hand (Zonet ZEW2501) worked much better than the Linksys WMP11 card. The maximum signal level was about 12 dB higher for the ZEW2501 than the WMP11. The ZEW2501 is tiny. The WMP11 is a more serious looking piece of hardware, but it performs much worse than the tiny dongle. Is there a lot of difference in the quality of different manufacturer's radios?
Many thanks for help.
Confused, Bruce