In working the same station some 300 miles away on a regular basis, I find
his signal to be about the same on the two antennas but the noise is less on
the folded dipole. Both the dipole and folded dipole are in an inverted V
configuration with the apex at about 45 ft They are mounted on a 6' cross
arm on the tower, one on the left and one on the right. Of course there is
some directivity due to the angle / broadside of the two antennas being
different by about 60 degrees.
I'd though about doing a field strength measurement over 360 degrees at a
distance of about 3 miles. The local terrain and site access in the area
makes that imposable. I could plot about 4 or 5 locations but I wouldn't
consider that few adequate. Otherwise, I've stomped through fields and
woods carrying a GR field strength meter making BC field strength
measurements but that was many years ago.
73
Bob, K4TAX
----- Original Message -----
From: "Carter" <k8vt@ameritech.net>
To: <tentec@contesting.com>
Sent: Tuesday, September 09, 2014 3:51 PM
Subject: Re: [TenTec] Eagle Tuner
On 9/9/2014 10:47 AM, Bob McGraw - K4TAX wrote:
> One thing I've clearly noticed about folded dipoles, the one I have
> on the tower is noticeable quieter, 1 to 2 S units, than the 75M
> dipole fed with coax on the same tower at approximately the same
> height. Now there may be some lobes that favor noise source,
> typically NW as that's where the storms originate, or slightly null
> to the noise source as the antenna are about 60 degrees apart,
> broadside.
Sorry Bob, but in all sincerity, I gotta ask...
If the *noise* is "noticeable[y] quieter, 1 to 2 S units", wouldn't the
wanted *signal* also be down 1 to 2 S units? Your theory about lobes and
noise has merit, but presumably the signal and noise would be affected
equally. (or could it be that the wanted signal is horizontally polarized
and noise is supposedly mostly vertically polarized?)
Inquiring minds want to know.
73,
Carter K8VT
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