[TowerTalk] C31-XR versus KT36XA

Fri Oct 3 16:40:44 EDT 2003

I had both kt34 and th6 in the 80's and 90's and found the 34 only
marginally better than the th6.  When moving to 7 land and complete new
tower etc etc I opted for the c31xr and can only say that i find it hard to
believe either of the 34 or th6 could compare to the 31xr.  It is just
killer on 10 and the only pileup i never broke was a 7O a couple of years
ago and although I could hear him I never heard him come back to any 6 or 7.
I am very impressed with the M2 stats and would love to see a field
comparison.  The c31xr also loads up rather easily on the warc bands,  just
keep the power down.
----- Original Message ----- 
From: "Jim White, K4OJ" <k4oj at tampabay.rr.com>
To: <bryanr at bometals.com>
Cc: <towertalk at contesting.com>
Sent: Friday, October 03, 2003 8:59 AM
Subject: Re: [TowerTalk] C31-XR versus KT36XA


> Brain - under the heading of - for what it is worth...
>
> That is me on that tower - the lower guy on the tower, and I used that
> antenna for about a decade at the station at my parents home in
> Homestead, FL until Hurricane Andrew took it down.
>
> In my opinion the antenna performed very well and despite those who told
> me it was a dog on 15 meters I came in second twice in the CQ WW CW as a
> 21 MHz monoband entrant - losing once to a ham in Virginia who
> out-Europeaned me (in Florida) and the other time to a W5 who out JA'd
> me...
>
> All that time I never felt the antenna was a disappointment - on the
> contrary it changed my opinion on tribanders to some extent. It was not
> the traditional "suckermaster" which presented a near 50 ohm low SWR
> antenna to the rig on three bands and not much more. It did have pattern
> AND DID BUST PILEUPS.
>
> The biggest downside of the KLM tribanders is a function of their
> complexity.  There were so many little pieces that it was that
> antithesis of the KISS (keep it simple stupid) rule and as I now gather
> from your posting is was so much  so we had it put together wrong!
>
> Even built wrong I could not think of another tribander on the market AT
> THAT TIME I would have rather been using.  Today, the multiple
> monobanders on a common boom triband antennas like the Force 12 antennas
> are to me more likely to have less problems and fewer assembly errors
> than the KT's.
>
> 73,
>
> Jim, K4OJ
>
> 203 11 59
>
>
>
>
> Bryan Rambo wrote:
> > Sorry for the delay Jim, I've been on vacation.
> >
> > The KT-34XA is constructed so that the coaxial capacitor sections are
> > oriented to the front on some elements and to the rear on the other
> > elements.  Going from the reflector to the last director, they should be
> > oriented rear-front-rear-front-rear.  The XA pictured in the Antenna
Book
> > article has all the capacitor sections to the front.
> >
> > I pointed that out just to show how easy it is to make a mistake when
> > building an XA.  I just wondered if the same mistake might have been
made on
> > the XA used in Steve's and Ward's tribander report.  I wonder if they
have
> > photos?  I also wondered if they ever confirmed whether or not the XA
used
> > in the report was one of those that had the defective tubing.
> >
> > 73 - Bryan W4WMT
> >
> > -----Original Message-----
> > From: Jim White, K4OJ [mailto:k4oj at tampabay.rr.com]
> > Sent: Friday, September 19, 2003 9:37 AM
> > To: bryanr at bometals.com
> > Subject: Re: [TowerTalk] C31-XR versus KT36XA
> >
> >
> > I am looking st the picture  -  how are those backwards?
> >
> > Thanks,
> >
> > Jim
> >
> > Bryan Rambo wrote:
> >
> >>Ward, thanks for your careful explanation below.  And again, I didn't
mean
> >>to imply that you had botched data in the tribander report.  Sorry for
not
> >>being more precise with my words :-(
> >>
> >>I wonder if it was ever confirmed that the KT34-XA used in the report
was
> >>indeed one of the units with defective tubing?  The reason I ask is that
> >
> > it
> >
> >>is very easy to put one of those antennas together wrong.  As evidence
of
> >>that, look in the ARRL Antenna Book (editions 17,18,19) in chapter 22
and
> >>take a gander at the KT34-XA depicted there.  Three of the elements are
> >>mounted backward on the boom!!!
> >>
> >>73 - Bryan W4WMT
> >>
> >>-----Original Message-----
> >>From: towertalk-bounces at contesting.com
> >>[mailto:towertalk-bounces at contesting.com]On Behalf Of Ward Silver
> >>Sent: Tuesday, September 16, 2003 11:50 PM
> >>To: Towertalk Reflector
> >>Subject: Re: [TowerTalk] C31-XR versus KT36XA
> >>
> >>
> >>A slight clarification on the exact problem with the KT34XA...
> >>
> >>When we started presenting data, as Steve said, several other XA owners
> >
> > came
> >
> >>up and said, "Mine acts JUST LIKE THAT and nobody has ever been able to
> >>explain why or fix it!" Other guys (the majority) couldn't repeat the
> >>behavior and had never observed it.  At Dayton in 2000, I was having
> >
> > dinner
> >
> >>with some DL hams (can't remember exactly who, apologies DL hams) and
they
> >>said, "You know, DL2? figured it out."
> >>
> >>To make a long and mysterious story short, KLM received and used an
> >>out-of-spec shipment of tubing for the 15-meter capacitor sections.  The
> >>capacitance is formed by the OD of the inner tube and the ID of the
outer
> >>tube.  The outer tube had the right OD, but the wrong wall thickness
(too
> >>thick) and so the ID was too small and the resulting capacitance too
large
> >>and the resulting frequency of minimum SWR too low. (Follow me through
> >
> > that
> >
> >>sentence?)
> >>
> >>The specified wall thickness for the outer tube was not the common value
> >
> > for
> >
> >>tubing of that OD. Somebody either ordered or shipped the common
> >
> > (too-thick)
> >
> >>tubing and KLM's QC didn't catch it.  The difference wasn't enough to
> >>prevent the plastic end caps from going in - it was just a few
thousandths
> >>of an inch too thick - so the problem went unsolved for years.
> >>
> >>If you have an XA that tunes up too low on 15-meters, contact M2 because
> >>they have a retrofit kit that will fix it up.  The suspect antennas
seemed
> >>to also have blue end caps on the tuning capacitor tubing, but it's not
a
> >>one-to-one relationship.
> >>
> >>Most of the credit goes to the DL guys for having the smarts to make the
> >>right measurements and deduce what had happened.  We published the data
> >
> > and
> >
> >>caused the connection between cause and effect to become known.  And
THAT,
> >>my friends, is why publishing your test data is so important.  That is
> >>SCIENCE, even if it is applied science.  As Isaac Asimov said
> >>(approximately), "Breakthroughs in science never start with 'Eureka!'
> >
> > They
> >
> >>start with 'Hmmm, that's funny...'"
> >>
> >>73, Ward N0AX
> >>
> >>----- Original Message -----
> >>From: <K7LXC at aol.com>
> >>To: <bryanr at bometals.com>; <towertalk at contesting.com>
> >>Cc: <hwardsil at centurytel.net>
> >>Sent: Tuesday, September 16, 2003 8:26 PM
> >>Subject: Re: [TowerTalk] C31-XR versus KT36XA
> >>
> >>
> >>
> >>
> >>>In a message dated 9/14/03 9:36:16 AM Pacific Daylight Time,
> >>>bryanr at bometals.com writes:
> >>>
> >>>
> >>>
> >>>>I'm glad you brought up the business about Steve & Ward's (otherwise
> >>>>excellent) tribander report.  It's a real shame that the ONE antenna
> >>>
> >>that
> >>
> >>
> >>>>got botched was the XA.
> >>>
> >>>   Actually several other XA owners told us that theirs were identical
to
> >>>the test antenna.
> >>>
> >>>   FYI any XA that came out of KLM once they moved to Washington State
> >>
> >>was
> >>
> >>
> >>>suspect since they made wholesale aluminum substitutions that created
> >>
> >>problems.
> >>
> >>
> >>>They couldn't get the parts from their suppliers because they didn't
pay
> >>
> >>them
> >>
> >>
> >>>so they shipped anything they had in stock that was close.
> >>>
> >>>
> >>>
> >>>>It sure would have been interesting to see
> >>>>how the XA stacks up to the more recent designs
> >>>
> >>>   Sure. Get us a KT36XA and we'll be happy to include it in our next
> >>
> >>round
> >>
> >>
> >>>of tests.
> >>>
> >>>Cheers,
> >>>Steve    K7LXC
> >>>TOWER TECH
> >>>Champion Radio Products
> >>>
> >>>
> >>
> >>
> >>
> >>_______________________________________________
> >>
> >>See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
> >>Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with
> >
> > any
> >
> >>questions and ask for Sherman, W2FLA.
> >>
> >>_______________________________________________
> >>TowerTalk mailing list
> >>TowerTalk at contesting.com
> >>http://lists.contesting.com/mailman/listinfo/towertalk
> >>
> >>_______________________________________________
> >>
> >>See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
> >
> > Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with
any
> > questions and ask for Sherman, W2FLA.
> >
> >>_______________________________________________
> >>TowerTalk mailing list
> >>TowerTalk at contesting.com
> >>http://lists.contesting.com/mailman/listinfo/towertalk
> >>
> >
> >
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk at contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
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