> So heres my ignorant question (kind of embarrassing too), does a larger
> yagi, i.e. going from 2 elements to say 4 elements improve receiving as
> well as transmitting?
There are no ignorant questions.
Here's how it works. Most low-band systems are noise or QRM
limited, so we can ignore the rig and absolute signal level fed to the
rig.
1.) If the noise (and QRM, consider that noise also) that limits your
reception is from the same direction as the desired signal, you can
stack a million antennas and nothing will change for receiving!
2.) If the noise comes from a direction where the stacking reduces
response, the S/N will improve by the ratio of that null to the
forward lobe increase. That can be many dB with a very small gain
change!
3.) If the noise is evenly distributed all around the antenna, the S/N
will improve by the same amount as the directivity increased.
Since we don't know about your situation, we don't know which is
fits best. It will be somewhere between no improvement and a large
improvement.
The main problem is probably your high power. With only four
elements and high power and absolutely no local noise, I have the
same situation. Dozens of stations call that I can't copy. That's
despite an S2 noise floor.
Very few DX stations have 1500 watts, and most run 100 watts.
Either you need a very special receiving array that has much more
directivity than the transmitting antenna, or your transmitting will
out do your receiving with the QRP stations calling you.
73, Tom W8JI
w8ji@contesting.com
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