Topband: Effect of Ground on a Dipole

[Roger Kennedy]

Hi David

Yes, I use RBN for comparisons these days . . . often get reports from US
stations of more than 35dB over the noise!  And obviously it's quite easy,
when some other British stations are on, to look at their reports and
compare.

And over the decades, I have done lots of comparisons, which is obviously
much easier on SSB. About 25 years ago I was one of a group of stations who
had skeds on SSB every morning for a whole year on 160 with a group of ZL
and VKs . . . all the others had BIG verticals (two had full-sized quarter
waves) . . . they were all amazed that I was consistently one of the
strongest signals. (even though I was running less than half the power of
most of them!)

Apart from the lack of space for radials, if I had a Vertical I'd want it to
be at least 80ft tall . . . and as I live in an ordinary street, I think the
neighbours would object!

However . . . propagation is completely different on 80m. DX is nearly
always low-angle . . . so without a good vertical your reports will always
be way down. So your idea for 80m is probably a good one.

Roger G3YRO

-----Original Message-----
From: David Cutter [mailto:d.cutter at ntlworld.com] 
Sent: 07 June 2018 18:58
To: 'Roger Kennedy'; topband at contesting.com
Subject: RE: Topband: Effect of Ground on a Dipole

Roger

I wondered if you'd considered the inverted L with a folded counterpoise ala
K2AV.  I'm seriously considering this with the 80m option for my very
limited garden and another site.  

When doing your comparisons, do you use the RBN?

Sorry, can't comment on your soil conductivity query.

David G3UNA

-----Original Message-----
From: Topband [mailto:topband-bounces at contesting.com] On Behalf Of Roger
Kennedy
Sent: Thursday, June 07, 2018 1:45 AM
To: topband at contesting.com
Subject: Topband: Effect of Ground on a Dipole

Well I did try an Inverted-L at one previous QTH Mike, but it was no better
for DX than my Dipole.

The trouble is that at this QTH I could never get a decent enough radial
system to make an Inverted-L work properly, as I don't have the space. (My
dipole goes outside my own property, but it's high in the air!)

But the other reason I stick with my Dipole is because I find that my DX
Signal on 160m (around the world) compares pretty well with other British
stations who use Verticals. (I have always put this down to the fact that on
Top Band most DX is fairly high angle, unlike on 80m)

I was hoping that more people would comment on my query that if typical Soil
Conductivity is as bad as recently posted on here, a dipole isn't really
that low above "ground", if the ground is so poor!  (this is also why I
think most computer modelling programs are so bad at showing how 160m
antennas work)

Roger G3YRO

------------------------------------------------------------

Roger, you should try an Inverted-L. :-)
http://www.w0btu.com/160_meters.html

73, Mike
www.w0btu.com



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