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Old July 23rd 12, 06:22 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default 315mhz/433mhz transmitter

On Mon, 23 Jul 2012 12:53:12 +0000, foxbrain
wrote:

so depending on the equation in :
http://tinyurl.com/c86y6q6
i should make the power the much larger i can but not more than 10mw
and so for the gain , and decrease the E (v/meter)....


Not exactly. When adding a bigger antenna, you will need to decrease
the transmit power to keep the field strength (V/meter) constant.

For example, assume that +12dBm tx power and 0dBm (unity) gain antenna
is the maximum legal. If you replace the unity gain antenna with an
+8dBi gain yagi, you will need to reduce the transmit power down to
+4dBm output to stay withint the maximum field strength requirement.

Note that you can calculate your maximum range if you know the various
numbers.
http://wireless.navas.us/index.php?title=Wi-Fi#Link_Calculations
http://www.terabeam.com/support/calculations/som.php



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Jeff Liebermann
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