Re: [smartBridges] Earthing

[Mark Koskenmaki]

You can build an antenna to be grounded... Or not.   The lower frequency stuff - particuarly that under 500 Mhz, often is created with the intention of having the earth itself be part of the ground plane, to help propagate the transmission.   Because of it's incredibly shorter wavelength, and the many wavelengths above earth ground, the effect on the radiation pattern is minimal.   While a 10 or 40 or 160 meter antenna is unlikely to be more than anywhere from 1/4 (or less) to maybe 5 wavelengths from the earth, there is a coupling that exists and is designed into the antenna.   Not grounding means that antenna is slightly "mis-wired" compared to its design.   I don't know the wavelength of 2.4 Ghz or 5.8 Ghz, but I'm sure that a vertical omni at 40, 60, or 100 or even 150 feet from the ground is so many wavelengths away the ground interaction is pretty much non-existent.       NEOFAST.NET North East Oregon FAST Net mark(at)neofast.net ----- Original Message ----- From: phantam To: '[EMAIL PROTECTED]' Sent: Friday, July 11, 2003 3:34 PM Subject: [smartBridges] Earthing How come on citizen band radios and many other frequencies the SWR is better when the antennas are properly earthed but in 2.4ghz no antennas are earthed. ? Wouldn't this clean up the signal and provide farther signal I just got to talking to a EX army engineer and he said that he doesn't understand why not and wants to try it but cant seem to find a SWR meter that can read 2.4ghz L   Chris --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.498 / Virus Database: 297 - Release Date: 7/8/03