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This looks like a transformation from a simple whip antenna to a J-pole antenna, but I'd consult homebrew antenna master of the aviation world: Jim Weir of RST Engineering.

Read Jeff Duntemann, K7JPD's book,
Wi-Fi Drive-By Guide...many
antenna projects, or just read a good amateur radio UHF antenna book....

woof woof, George, WA8WTE

I'm not quite sure that an antenna can double your power output, but I could be wrong

I've built a few and the only ones that made any worthwhile difference were a waveguide made from a premium brand Whisky container and a Bi-Quad. None of the toothpick designs gave enough gain to make much difference at all. It may be that commercial omnis are worth it, but I couldn't make them accurately enough to succeed. And 5dB difference is pretty hard to see in the real world of PCs and Wifi.

"I'm not quite sure that an antenna can double your power output, but I could be wrong"

You can double your power output by increasing your gain in a field of radiation by 3dB. Of course, it decreases it from somewhere else in the model, but generally speaking, it is somewhere like the extreme top and bottom where coverage is not needed. The more gain you have on the sides of an antenna, the more of a coverage null you will have on the top and bottom, or vice versa.

Looks like a vertical antenna with a load coil. I'm not sure how you could measure efficency without at least looking at SWR. I don't see a groundplane; anything near it would change the pattern.

2.4 GHz is pretty unforgiving dimensionally for any frequency, just a mm or two will throw off SWR and completely change your radiation pattern. Plus it has to be a wideband system since it uses Spread Spectrum of over a hundred MHz.

A good program to model an antenna is at
http://mmhamsoft.amateur-radio.ca/
Look for MMANA-GAL. It works best for lower frequencies, but it will give you an idea of how shapes affect antennas.

I call shenanigans as well. I had an extra base here for my router, and for my wireless NIC. I made up two of these antennas, and tested them in every possible configuration.

Conclusion: Negligible improvements, could be attributed to error. I placed the laptop in the same spot for each test, but I had to move the router around quite a bit to get the new antennas in place. Also, the new antennas were significantly more 'flimsy' and were easily bent out of shape--which made SNR TERRIBLE.

It would be a better idea to move the router to a much better location, and give it a bigger antenna than to mess with your laptop's antenna anyway.

Yes it can double the power. Antennas can have "gain" but as the poster above said it is because you are taking the power and concetrating it. There are antenna designs that can do far more than double, look up "yagi" for instance.

There is an error in this report howver. Doubling the power does not double the range. For this type of antenna doubling the power will get you a little more range but not double.

I doubt that antenna will even help. youll probably make your cheap antenna worse by adding poor quality wire and bad connecting methods you will lose gain and pickup more nose. More noise will be received due to the sheer inconsistency of the above design as screws taper and have different angles and distance between teeth this depends on sheer luck. If you have never used a soldering iron or taken anything apart your wasting your time because it could take hours of fine tuning and even then it could be a total flop.

This WOrks thanks alot :)

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