is it possible to use a extinding car antenna for wifi i would have it on the front right of the drives (if your looking straigh at it ) then have it go up whenever in use. Full of great ideas but no money or resources to finance them
Simple answer, no. Complex answer: For an antenna to work well, it has to be tuned to the frequency of the signal going out through it. This is like a tuning fork, the tuning fork resonates an a specific frequency that is determined by the material, shape, and size of the resonator. To determine the correct size of an antenna, divide the speed of light (in meters per second) by the frequency (in HZ i.e. cycles per second). The average wavelength for 802.11b and g is 12.5 cm. For an antenna, you use a fraction of this value. 1/4 wavelength seems to be the usual length (I don’t know if this means it works better or is just smaller). 802.11b is not exactly 2.4 GHz but it is close. If you wish to calculate the right length for each channel, find the frequency here. You can cut your car antenna to 3.6 cm in length, then it might work for a wifi network, or you can keep it the length that it is, but you will probably destroy you wifi card. A much better alternative is to build or buy a simple monopole or dipole antenna and put a suction-cup on your roof with the antenna cord going through a window.
reading this post has made me more motivated to mount my satelite dish outside my window so i can see other APs....
agreed. you are entering the wild wacky world of wireless, nothing is as it seems. it all has useless and out of this world physics behind it.
Blue Raven's right - it has to be a certain length along the lines of the wavelength. From a little research awhile back it seems the bigger the better - 1/4 length just being smaller and more handy for limited ranges. What happens is that if you go too long or too short some of the signal goes back down into the transmitter (you can get PWM and back EMF metres if you want to spend money - but hey). When it goes back into the transmitter, it heats up and drastically shortens it's life and the range of your equipment. So it only effects the transmitter, which is why it doesn't matter for TV's and radios etc. But if your car effort's around 12.5cm, you could give it a try...
another question to all you wifi gurus i have an old dish is the focal point that the dish used will that work for a wifi thinger and what if the focal point is a little bit off how muhc will it affect the single
focal point is used only for directional antennaes ith a corect length omni directional antennae, or other object, so there for side effects arent nearly as bad.
I agree with ArmyAnt. The focal point is not very exact. It can be moved side to side or a bit in and out. If it is a bit too close or far out, then the signal just won’t be focused as well but it will still get much better gain that with an omnidirectonal antenna. To use the wifi card with you satellite dish, you can mount the card at the focal point or shoulder an antenna onto the card and mount a cantenna pointing at the dish. This will even more increase the range. The reason a directional antenna gets so much better range is because it points all of the energy in the same direction.
Everything said is all I know as well - but you might be interested in http://www.wwc.edu/~frohro/Airport/Primestar/Primestar.html They use a normal dish... Also see... http://www.techtv.com/screensavers/howto/story/0,24330,3406172,00.html and http://www.turnpoint.net/wireless/cantennahowto.html That's got info on the cantenna.
best ive seen/done so far are making an amp from online scematics, then a cantenna wih USB inside on a prime star dish, and my bud is an electrical engineer, and he said he could pick up LOS signals from his roof up to 5 miles away.
Do you have a link to that amp you built? those things are REALLY expensive and I'd love to put a couple together.
