Our club has a new member who builds antennas, but he cannot get them to work. I am a complete beginner with the technology myself and have a simple question: how do we measure if the antenna is working properly? I've tried all the easy ways.

The antenna must pick up a current. But we have tried everything in our limited arsenal to detect that current, including connecting a 20,000x Darlington pair. Nothing. We've tried diodes, all possible grounding configurations, capacitors, and connected the antennas to every major brand of wireless router with no success.

Is there a simple solution we are missing? Some way to connect things as a quick check? We know about SWR meters, but are seeking to measure the induced current before spending money on gear nobody here yet knows how to operate. We are Arduino buffs, not technicians.

Thanks in advance to anyone who helps. We will reciprocate wherever possible.

-veryatlantic

PS: Our new member does beautiful work. A talented builder but no radio background, he literally builds antennas after seeing Internet jpegs. His wiring is correct, and he's built a folded wave dipole and a quad bow-tie, everything checks out. Please don't ask for the antenna specs, that is overthinking the question and we don't need help with that aspect. These are ordinary antennas you can find anywhere. The wiring is correct, we just need to know the easy way to test things. Searching on-line is not the answer. We wasted six hours and all we got was sniping from pontifical old geezer "experts" who's faces would freeze if they ever gave anyone a straight answer. They kept telling us to study "basic antenna theory". (Maybe they should study the concept of "basic end-user".) Please, no links to ham sites or radio clubs, they are no help and we would like to hear from only those capable of formulating their own replies.

 

Hello,

What you need is a fieldstrength meter.
Here is one example:
http://www.qsl.net/n9zia/wireless/pics/fs_meter.png

Here is also a list of linkpages with designs of wifi antenanas:
Biquad antenna
Cantenna
WIFI antenna applications
WIFI - WLAN antennas
WLAN Antenna Tools
WLAN-Biquad Antenna
WLAN Netgear PCMCIA card
WLAN-Parabola


Bertus

 

Having knowledge of that basic antenna theory would be quite helpful. One suspects that antennas operate somewhat differently than you have imagined.

 

Interesting replies so far. But they totally missed the point by not reading the original postscript. PLEASE, no links. We wasted six hours on that. And PLEASE, no advice to go back to school. We just want to know what time it is, not how to build a clock.

Is there anyone out there who will read my original post, grasp that we already have the antennas, we just need to know how to hook them up and test them? Bertus sends links to a site with 37 subfolders without specifying which, in his super moderator opinion, tells us how to hook up an antenna rather than to build one. And Beenthere, who suggests we missed the boat on antenna theory, well, he should be aware America already has a cartoon team with a moniker similar to "Bertus & Beenthere".

I hope you guys don't feel insulted, but if you do, remember: you started it. Now, once again, I ask, can anyone tell us how to connect an antenna to test if it is good or not without buying or building special meters or returning to college.

PS. We know it can be done because there was an old guy in our shop who used to do it all the time, but he's gone. He would unscrew the stub from an ordinary wireless card, connect the DIY antenna, and somehow read the gain or ratios or decibels or something. We are asking if anyone out there knows how to do that, and asking everybody else to politely not reply at all. Fair enough?

 

A closed mind gathers no knowledge. You have to learn something about RF and antennas.