There are a few details missing that may affect the answer. Is the
noise atmospheric noise or man made. "S9 hiss" doesn't sound like a
description of atmospheric noise. Are you measuring signal-to-noise on
DX stations or local stations. How high is the inverted vee.
A low inverted vee is a noisy antenna for DX. A high one isn't bad. If
you are listening to DX on the 40 meter element of a SteppIR, my guess
is that common mode currents are a major contributor to the signal you
are receiving. Same as I found out about receiving on 160 using my
XM240. It was better than a low dipole. In that case the feedline was
the real antenna , not the XM240, caused by its balun not working on
160. I even checked the SWR on 160 into that antenna and it was fairly
low, which is another confirmation that the common mode currents on the
feedline was a major contributor. No I didn't try transmitting on it.
So, in this case a vertical had a better signal-to-noise ratio than a
low dipole for DX. That should come as no surprise to those living in a
rural area. If you happen to live in a city, then we may be talking
about a different kind of noise.
DC coupling the antenna should have no effect on the noise. A double
bazooka configured as an inverted vee should have the same signal to
noise ratio as an inverted vee. The double bazooka will have slightly
less gain, but the S/N will be the same.
Atmospheric noise has been pretty bad on 80 lately due to all the
thunderstorms. A receiving antenna can help a lot, but when you have
thunderstorms close by and the receiving antenna points into them, there
isn't much more you can do.
Howard R wrote:
>Can anyone recommend a way to reduce noise on my 75 meter inverted Vee or
>alternately I am looking for a quieter antenna , I am using a current fed
>balun and seems to me if I can dc couple the 2 quarter wave sections perhaps
>I can reduce the noise somewhat . Any help would be appreciated .
>When I use my folded 40 meter driven element on my Steppir for 75 meter
>receive my S/N ratio is around 40 db with my balun fed inverted Vee its
>around 15 db always have S9 hiss .
>I was looking at a double bazooka as a replacement perhaps . Any comments.
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