[Elecraft] OT: Ground Loss (long)

[Guy Olinger K2AV]

It's kind of interesting that hams see buried/on ground

On Saturday, July 25, 2015, dyarnes <w7aqk at cox.net> wrote:

> Hi All,
>
> I cannot improve, or add much to, the excellent commentary provided by Jim
> Brown and others.  However, I can say that my "experience" tends to confirm
> a lot these findings.
>
> First, I originally had an R7 vertical ground mounted.  Performance was
> "O.K.", but certainly not very exciting.  Later I elevated that antenna to
> about 15 ft. above ground, and the improvement was very noticeable.
> Subsequently I have replaced the R7 with an F8 (acquired in an estate
> sale), and the results are very much the same--the antennas are not all
> that much different anyway, but the R8 is a bit taller, and does cover 6
> meters (after a fashion!).  If you look at the study Ward Silver, N0AX, did
> many years ago on various vertical antenna systems, the R8 is rated one of
> the very best. In any event, I've worked well over 100 countries QRP on 40
> meters using this arrangement.
>
> After hearing Rudy Severns' presentation about ground systems at Pacificon
> several years ago, I began elevating radials when using my portable antenna
> systems while camping.  Most of this was done using either an MP-1 or a
> Biddipole configured as a Buddistick.  Again, the results were very
> rewarding.  As Rudy indicates, elevating your radials even just a small
> amount can result in significant benefit.  Usually I try to deploy 4
> elevated radials.  Sometimes, though, only 1 or 2 are practical under the
> circumstances.  Still, it helps!
>
> I also acquired a used Sigma 40XK, and now use it as my primary 40 meter
> antenna at home.  That antenna is raised about 6 feet off the ground, so
> the overall height is about 20 feet or so.  I wish I could go higher, but
> neighborhood restrictions prevent that.  I get a 1 to 3 Db improvement with
> this antenna over the R8, measured by comparisons using the RBN system.
> I've become a big fan of vertical dipoles!  When I go QRO (500 watts for
> me), I get some reports from DX stations that I consider to be exceptional.
> I also monitor myself on the RBN, so I have some idea as to who might hear
> me and who can't.  It's almost better than trying to interpret some of the
> propagation software.
>
> I also have one of N6BT's Bravo 7 antennas, which he calls vertical
> dipoles also.  By the way, N6BT also designed the Sigma 40KX when he owned
> Force 12. Anyway, the Bravo 7 works pretty well as a portable system, but
> I'm not quite as happy with it as a 40 meter system.  Still, it is very
> portable, and easy to put up and take down.  N6BT makes some pretty
> aggressive claims about the performance of this system, but I am pretty
> sure most of his "testing" was done over salt water.  In any event, the
> higher up I deploy that system, the better it seems to work.  I think Jim
> Brown's suggestion of adding a better radial system to vertical dipoles may
> be exactly what I need to try and do with the Bravo 7, particularly for 40
> meter operation.
>
> Soil conditions here in Arizona are pretty awful.  It's not very often
> that I go camping anywhere that offers anything much better.  Deploying
> elevated radials can be problematic, but it certainly seems worth the
> effort most of the time.
>
> Dave W7AQK
>
>
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