SWR and noise reduction
On 6/28/2012 6:39 PM, Channel Jumper wrote:
The RG 8X was used as phasing lines - was the tuneable matching
network.
I doubt it.. He seems to be feeding a single dipole, using
twin runs of coax as an expensive type of ladder line. :/
Maybe what the person intended to say was that they tuned the antenna
for a different frequency / hence at the frequency they desired to use,
was a poor match with that antenna.
It stands to reason, if the antenna was not resonant, it would not
receive as well at X Mhz.
It would almost surely be a matching issue though. The length
of the dipoles, or being resonant or not, doesn't really matter
too much. Almost any length dipole will radiate almost all
power applied to it. The trick is getting the power to it, and
not turning some into heat in the process.
And reception is reciprocal vs transmit.
I don't buy the claims of better signal to noise ratio.
Adding loss is going to lower the level of all received RF equally.
Actual signals will be reduced at the same ratio as any noise.
So at the end of the day, the s/n ratio should stay the same.
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