[WVDXA] Yesterday's 6m take...

[W8TN - Clark]

Dave,

     That ZB is a hard one to catch.  Phil, W8UV, recently stated here on
the Reflector that he has chased ZB for 30 YEARS on 6-M!  I got lucky
(thanks to a phone call from Gary, W8OI) and snagged ZB3B on July 5, 2004.

     You are absolutely correct on the antenna height for 6-M.  Sometimes
higher is NOT better.  We are used to thinking that the most metal you can
put - as high as you can put it - will work best, but not so on the Magic
Band.

     The big-time 6-M contesters and DX'ers have multiple 6-M antennas at
various heights and switch between them to find the one that works best on a
particular path.  It has always amazed me that a 3 or 4-L yagi at 20 feet
can out-perform an antenna twice or three times as large at 70-feet!
Sometimes so much so that the big antenna just does not even HEAR the
station and he is LOUD on the low, small antenna.

     Here is a good discussion of the subject by K5TR:

http://lists.contesting.com/_vhfcontesting/2001-07/msg00046.html

     And, here is a good discussion of the "real-world" performance of
different antennas at different heights by K1SIX.  K4OM should note the
construction/installation details on the 50-foot long, M2 6M9KHW (since I
sold him one of those):

http://k1six.com/2MPIX.html

     To further indicate how interesting (and confusing) 6-M can be, the
following PDF file that discusses the installation of two M2 6M7JHV yagis)
makes this statement:

"Interestingly the top antenna although only 13 feet above the lower gave
better results on most DX signals than the lower antenna."

     Two identical antennas, only 13 feet apart, yielding different results.

http://www.arraysolutions.com/images/Six%20News%20ArticleSMII_phsshifter.pdf

     Finally, here is an excellent discussion of using "ground-gain" on
6-M.  This is an addition 3 to 6dB of GAIN which is added to your signal
BECAUSE of your antennas proximity to the ground!  In this discussion, W7GJ,
shows how smaller antennas can be used to achieve moon-bounce on 6-M by
utilizing this "ground gain" effect.  It is obvious that this effect can be
used to work terrestrial stations as well.

"The closer the antenna is to the ground (or some other object or antenna
below the antenna that looks like ground), the higher the ground gain lobes
are raised.  Conversely, the higher the antenna is above the ground, the
lower the ground gain lobes.  It also is not unusual for an antenna that is
only a few wavelenths high to have an excellent lower ground gain lobe if
the distant horizon is actually a negative horizon.  This situation
frequently happens when a station is located on a hill, or the terrain is
flat or dropping away in front of the antenna. "

http://www.bigskyspaces.com/w7gj/Welcome_to_6m_EME.htm

     So, the answer for those of us who want to work that elusive 6-M DX is
to have more than one 6-M antenna and to have those antennas at different
heights.  Also, it is good for the "small pistol" types to realize that even
though they only have a 3 or 4-L antenna at a low height, they just might
have the best antenna for a particular path and can actually beat out the
"big-gun" station with the high, long boom antenna.

     Note that our 6-M Big-Gun, Phil, W8UV, has a Hy-Gain 66B (6-L on a
24-foot boom) at 90-feet and another one at 60-feet on a separate tower.  I
expect he may even have a third lower antenna as well but don't know that
for sure.

     Oh, as an aside, I think the "brand new ham" you are speaking of might
be "K*B*3RHR" as I just received a QSL from him.  I figured he was a
"newbie" because his QSL says "UTC/EST" and he underlined the "EST" and put
the time down as "9:30" for our QSO.  As we all know, you should only use
GMT (UTC) on your QSL's.  (And, it is currently EDT not EST!)  Nevertheless,
I was glad to get the card as it is a new Grid confirmed for me.


Clark, W8TN
*Still Learnin' 'bout 6-M*

Note:  I'll save the discussion on "space diversity" (identical antennas at
equal heights but on separate towers WILL hear the signal differently at
different times) for a later time.



At 7:03 a.m. on 13-July-2008 K8MN wrote:

> I could barely hear the ZB in there. While his signal was up and down,
> it was never good enough for a QSO. EA4UW was deaf as a post and I
> heard none of the Italians.
>
> I ended up with four QSOs with EA8 and three with CT. Nothing wrong
> with that but there was nothing new in there either.
>
> Until I went overseas in the 1980's, my experience on 6m was limited to
> mostly domestic QSOs, a lot of them with Cincinnati area locals. I had
> an old three element Cushcraft yagi at 45 feet. I used that old
> Heathkit heavy boatanchor HX-something-or-other SSB transmitter with 20
> or so watts along with an HQ-170 receiver and followed that up with the
> Heath SB-110 transceiver at 100 or so watts. My only "big gun"
> operations were at VHF contest superstation WA8ONQ in Middletown, Ohio
> with ops like K8LEE, WZ8D (then WB8IGY), K8VVV, WA8OGS and others. If
> it wasn't for that experience and the encouragement and help of those
> ops, I'd not have been able to pull off some of the stuff I did from
> overseas.
>
> As far as humbling experiences, I listened yesterday as brand new ham
> KD3RHR, not twenty miles airline from me, worked the ZB station with
> relative ease. It was at that time that it dawned on me that sometimes
> a lower antenna might be needed. 'RHR has (I believe) a 4 element yagi
> at about forty feet.
>
> 73,
>
> Dave K8MN
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