On Jul 23, 3:34*am, "Andy" wrote:
I've swapped the feed line over and its still the same.

When I put the antenna together I made sure all connections where good and
the analyser gave a good match on the frequencies I want to use.

I did use some conductive grease for the first time on the antenna. Wonder
if the grease is the problem or maybe this antenna just picks up a lot of
background hiss.

Noise is RF the same as any other signal. The only exception would
be bad connections, etc that cause "locally generated" noise.
You need to find out if the source is received, or from a local
problem.
The SWR means little as far as receive. Any difference in level
due to SWR changes should be very small, and it would not effect
the s/n ratio if it did.
Does rotating the antenna vary the level of the noise? If so, the
noise is most likely received. You should be able to semi null
it out using the right direction if this was the case.
I doubt the element connections are the problem, or you would
see sudden spikes in the SWR when the connections flaked out.
What band is this on?
At this point just not enough info to tell what the deal is.
I could tell a lot more if I heard it. Can you record a sample
and post it somewhere?
Like I say, there should be little if any real difference in s/n
ratio if both antennas are pointed in the same direction.
Even if one had more gain in that direction, or was more
efficient overall, this would not effect the s/n ratio.
Noise and desired signals should increase in a linear
fashion.
IE: If antenna A receives the base noise level at S5, and the
desired signal is S8, and then you switch to antenna B
and the base noise is S7, and the desired signals are S9+,
they should still "sound" the same through the speaker.
The noise shouldn't seem any louder on antenna B, as
the desired signals and noise increase at an equal level.
This is why I say overall, it doesn't make much sense.
The reason I asked about the noise blanker is they
really degrade the dynamic range when strong signals
are present, and many overlook this while trying everything
else in the book. But.. A NB usually causes more of a
distorted audio sound, not static.
Do you get this same static when the band is "dead"?
That would tend to point to a pretty close noise source.
Either locally generated by bad connections, etc, or a
noise source nearby that is received normally.
But like I say, if you receive the noise, you should be
able to effect the level by turning the antenna.