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I have an old 48" CB whip antenna Can I modify it and use it for a wifi antenna or anything else you can imagine? Answered

Its a white antenna CB whip Antenna that my dad use when he was a long haul truck driver. I kinda understand that CB & wifi are close in theory. If I can use it, it would be a fitting tribute to him. It was my father who always inspired me to always look beyond the standard and as he always told me, " If you can read, & not afraid to ask questions, you can do anything."  Here are some pics: http://img88.imageshack.us/g/topofantenna.jpg/



.  CB radio operates at, and your antenna is tuned to operate at 27 MHz. WiFi uses 2.4 GHz. I don't know enough about antennae to say exactly what that means, but I'm guessing your antenna will be much too long to operate efficiently with WiFi.

Thank you NachoMahma, cory.smith, orksecurity. I appreciate the great info. Oh well, it was a worth a try or is it a thought!?! Whichever.

Agreed. Antenna length is important, and they operate based on wavelength. CB radios use a 2 meter wavelength, so most of them are configured to run a half wave antenna, therefore 1 meter long. wi-fi antenna also operate a half wave antenna, but that is something on the order of 4 inches, for an 8 inch wavelength.

this link has dozens upon dozens of antenna resources...



@ cory.smith
CB uses a 11 meter wavelength.
2m (and 70cm) is for licenced radio amateurs, not CB :)

Electrical engineer with specialties in radio.
Straight antennas, like the one you have, have to be 1/2 the wavelength. If it is too long or short, then the nodes of the sinusoidal wave will not meet with the ends of the antenna, causing both destructive interference and operating (poorly) on a different frequency.
You can calculate the wavelength by simply dividing the speed of light by the frequency, in hertz. This answer will be in meters, and is the length of one full oscillation (the wavelength). In order for the antenna to work, you need to make it 1/2 this length, for the reason i specified above.
So, to use that antenna for wifi would be a matter of bringing it down to the 1/2 wavelength of 2.4GHz. That being difficult enough, here's another problem....
I noticed in the photo how that antenna actually uses a coil, and it is wrapped at intermittent turns per inch, or TPI (they get closer and closer as you go down the antenna). These graduated coil TPI antennas have been designed to work, as a full length antenna, at a specific frequency. Cutting it back would mess it up.
I recommend you don't try to cut this thing back and make it into a wifi antenna... buy a CB and play with that (it is a nice CB antenna).

If you could get the CB antenna to work, it would probably act like a long wire antenna and be rather directional ... you'd have to have the recieving antenna in the right direction from your location.

Long wire antennas tend to send the signal off at an acute angle ( somewhat along the wire) to the antewnna instead of off at right angle ( sideways).

If you want to use the antenna to memorialize your dad as one of the "Kings of the Road" ( I'm an ex-trucker, btw), may I suggest you make a display with the antenna, and some pics of him and his rig. IMHO, that would be cool.

Probably not the right length or loading to work well for anything but CB frequencies. But that's a guess.

As always, note that modifying the antenna on consumer electronics puts you outside the FCC certification for those electronics. If anyone complains that you're causing interference, they can force you to shut down.