CB Antenna ?'s
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From: Milwaukee
CB Antenna ?'s
I would love to put a CB radio in my 00 F-350 DRW. However, I don't want a huge antenna on the truck. Does anybody know of an antenna that has good range and is small? I've seen some that are about 6" long that mount to the glass, like a phone antenna. As nice as those are, I hear that they only have range of about 1 mile. I would also like this to be a solid, long-term mount, not a magnetic or suction mount. Another user from the 7.3 PSD fourm told me about antennas that are mounted on the mirrors! I really like the idea of 2 mirror mount antennas. Something short, but with range. Something that looks stock on the power towing mirrors. Anybody knows more or has pix, tell or show me! Please!
Thanks,
DC-9
Thanks,
DC-9
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DC-9-
Sorry, laws of physics apply. CB has a wavelength of roughly 11 meters... short antennas are roughly equivalent to dummy loads. For my CB antenna, I have a Larsen NMO 27 lip-mounted from the hood, straight across from the AM/FM antenna. It's inexpensive and looks fairly stock.
As far as the 6-inch antennas, you'd be about as well off by tossing a 50-ohm, 10-watt resistor across the antenna connector.
Sorry, laws of physics apply. CB has a wavelength of roughly 11 meters... short antennas are roughly equivalent to dummy loads. For my CB antenna, I have a Larsen NMO 27 lip-mounted from the hood, straight across from the AM/FM antenna. It's inexpensive and looks fairly stock.
As far as the 6-inch antennas, you'd be about as well off by tossing a 50-ohm, 10-watt resistor across the antenna connector.
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From: Milwaukee
Well maybe not 6" but 2 or 3 feet tall. Something that isn't too much taller then my AM/FM antenna. But I really want them mounted to/inside the mirrors so that only the antenna sticks out from the top of the power tow mirrors. If possible, all antenna hardware stays out of sight inside the mirror housing.
DC-9
DC-9
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From: Dayton, OH
You can determine the proper length of an antenna by using a formula:
Wavelength (in feet) = 984 / frequency (in megahertz)
The CB portion of the spectrum begins at 25.01 megahertz, so a full wavelength antenna would be a bit more than 39.34 feet long. That's obviously a little long to attach to your bumper, so people tend to use antennas that are a fraction of the wavelength: 1/2, 5/8, 1/4 and 1/8 are all common wavelengths for antennas. In the case of CB, the 1/4 antenna at just under 10 feet long is the common "whip" that you may see on cars and trucks.
The trouble is that there are 40 channels on modern CB transceivers, each corresponding to a different frequency. It's not practical to have a separate antenna for each frequency, so antenna designers have to compromise, usually picking a frequency in the middle of the spread and choosing the antenna length to correspond.
Whatever you give up in antenna length you're also going to lose in reception/transmission capability. Also, because we're talking about a dipole antenna we can't really play with directivity to gain performance.
The mirror mounts would be good for something in the vacinity of 1/4-2 miles plus, depending on atmospheric conditions. There are a number of different ways to use antennas to gain distance or directivity. You can play with the laws of physics, but you can't beat them.
Wavelength (in feet) = 984 / frequency (in megahertz)
The CB portion of the spectrum begins at 25.01 megahertz, so a full wavelength antenna would be a bit more than 39.34 feet long. That's obviously a little long to attach to your bumper, so people tend to use antennas that are a fraction of the wavelength: 1/2, 5/8, 1/4 and 1/8 are all common wavelengths for antennas. In the case of CB, the 1/4 antenna at just under 10 feet long is the common "whip" that you may see on cars and trucks.
The trouble is that there are 40 channels on modern CB transceivers, each corresponding to a different frequency. It's not practical to have a separate antenna for each frequency, so antenna designers have to compromise, usually picking a frequency in the middle of the spread and choosing the antenna length to correspond.
Whatever you give up in antenna length you're also going to lose in reception/transmission capability. Also, because we're talking about a dipole antenna we can't really play with directivity to gain performance.
The mirror mounts would be good for something in the vacinity of 1/4-2 miles plus, depending on atmospheric conditions. There are a number of different ways to use antennas to gain distance or directivity. You can play with the laws of physics, but you can't beat them.
Last edited by Jlower; Sep 18, 2005 at 10:48 AM.
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