Thread: Field Strength
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Old December 13th 03, 06:40 AM
Scott Stephens
 
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Paul Burridge wrote:

Does
anyone have any idea what the field strength in microvolts or
millivolts is from a half Watt transmitter at about 6 feet away?


I'll SWAG & hope I'll be corrected if I tell ya wrong. Assuming a 1/2
wave antenna on the xmit & rcv, take the volts/meter you're applying on
the antenna, divide by 4 PI / (distance)^2, with distance being in
wavelengths.

Then there is the famous propogation equations which involves 32,
recieve and transmit antenna gains, and the log of the distance and
frequency. You can then go from power to voltage according to the
antenna Z. I'll look up the equation for you if you don't get a better
answer.

--
Scott

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