That reminds me. Did you ever get the test results report? From the eBay store page:
Q: exactly how much of a DB gain does this give you? A: We are waiting for the report to come back. But I know it will keep up with a 14 db panel antenna and a 500 mw amplifier. So I am guessing around min 26 to 30 db gain to the computer.
How about the specification sheet? Q: I have a local wireless computer networking business here in the boonies 2 hours west of Chicago. But i am interested in your device. Where can i get full specs on it, including transmit power, ability to operate with linux drivers, etc? A: We are in the process of putting a specification sheet together. I know that it can keep up with a 14db panel antenna plus a 500 mw amp. Only have drivers for windows. But will be adding them.
I didn't know antennas required Windoze drivers.
It's not very difficult to do relative gain measurements. (Absolute gain is a challenge). Use a reference antenna, with a known gain, and compare signal strengths with either a client radio with signal strength indication, with an external attenuator, or with a spectrum analyzer. The only real trick is to not do it on a roadway or across a rooftop to avoid ground reflections. Over a canyon or plowed field works nicely. Try to get both ends at least 10 ft off the ground.
Once you have a setup that yields reproduceable results, you can easily measure vertical and horizontal -3dB beamwidth and patterns. The problem is that the pattern will not look anything like the computer generated simulations due to construction variations, reflections, VSWR, measurement errors, and junk pickup. However, it's better than nothing.
Measuring VSWR from 2400.0 to 2483.5 is easy with a directional coupler, sweep generator, RF detector, and oscilloscope. You can build a crude but functional directional coupler out of some semi-rigid coax cables. The signal source is a problem, but I have some tricks that might work. RF detector and scope are common.
I'm not at all interested in becoming part of what I'm guessing is going to be a legal problem. I do evaluate products and write copious and detailed reports with recommendations and analysis. I charge quite a bit but less than a professional lab with lots of test equipment.
In all cases, I sign an NDA (non-disclosure agreement) where all results and equipment are property of the manufacturer. I am not allowed to release any information on what I've found. That's why I can't post performance measurements on some wireless devices. The numbers belong to my client. I've also been very lucky in that my results and testing has been used by the client in an honest manner. This is not universal as some of my friends and competitors have had their test results edited, tweaked, or butchered, by the client.
Anyway, it's all academic because I just picked up a design project, need to fix the house a bit, wanna spend some time away from computahs, it's tax time, and wanna do a vacation. For the price of an antenna, no thanks.