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Re[2]: [TowerTalk] TH7 versus KT34XA

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Subject: Re[2]: [TowerTalk] TH7 versus KT34XA
From: (Dave Raymond-CSUS04)
Date: Thu, 26 Jun 1997 13:31:00 -0500
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     The KT34XA stack sounds like a very successful array.
     I have 3 TH7s stacked at 40', 80', and 120'.  Performancewise, it 
     compares very well against three and four yagi monoband stacks with 
     antennas of larger boomlengths.  Overall, I'm very pleased with it's 
     I like the TH7 antenna because of its ruggedness and simplicity of 
     construction.  I also like the ready availability of good support and 
     repair parts from HyGain.  In the eight months its been up, the array 
     here has been exposed to 75+ mph winds on three separate occasions.   
     Winters here in Iowa are no picnic.  So far, the TH7s have held up 
     just fine.

______________________________ Reply Separator _________________________________
Subject: Re: [TowerTalk] TH7 versus KT34XA
Author: at EMAIL
To: <>
Date:    6/26/97 11:17 AM

Have 3 kt34'xa in a stack.....i went with kt34xa's becuz if the 
success of certain well known contesters who used a
single kt34xa at 70' to kick butt for years.......Dan Honda 
w7wa.  I also like the broadband characteristics of the double 
driven element design.
kt34'xas are a bitch to build (at least very time consuming) 
and if u make an error early on in construction you get to
rebuild them !!  but if u take ur time and follow the instructions 
to the letter and remeasure each element CAREFULLY before
putting the antenna in the air it will wk as advertised.
My three are at 92,132 and 172' a bit high some mite argue? 
Actual performance for me is still a bit of a question mark since 
have had only 20m prop to run checks on.
I have an old Telrex TB-6 on another 105" foot twr as a reference 
........sometimes the stack  is no better than the single tb-6.... 
sometimes the stack is btr but  not by as much as i wud like (6-8db) 
considering the investment  in aluminum. and effort in putting them up!
I am hoping they will do btr on 10-15.    Had a incident in the AA 
test this past wkend on 15 where a few JA's were leaking thru
on the stack but i cud not hear most of them on the tri-bander!! 
will see......
yes the swr is higher on 15m as they say it will....but in general the 
swr curves on mine follow the curves in the book.
in summary you can not take enuf care in assembling these puppies.
when i first got my three i hurried into construction for a solid week with 
a helper only to find out when i went to put the 1/2 elements on the
booms that idiots had shipped me kt34's by mistake (not xa's) so i had 
to restart from scratch....needles to say i was pissed.
best solution to putting a kt34 together is to find someone that has done 
it b4 if u can it will make a hell of a difference.......
> From: David L. Thompson <> 
> To:
> Subject: [TowerTalk] TH7 versus KT34XA 
To: <>
> Date: Thursday, June 26, 1997 7:45 AM 
> Bill, W4AN is right..the KT34XA is a pain in the butt. But when it works its 
> great.  Mine was beat up by Opal in Oct 1995.  The reflector has flipped
> over and is now upside down.  15 meters has high SWR.  20 meters requires 
> the tuner and it keeps changing tuning.  I have replaced caps twice since 
> 1981 when I got it...and I have a crank up so I can bring it down to roof 
> level to work on it.  Altho cranking it down is a chore.
> I would suspect the problem with the TH7 would be the traps. 
> Now someone at Hy-Gain passed the word that the TH11 has improved
> performance on 10 and 20 over the TH7.  Is this selling hype or truth? 
> I run across a few who swear by the Sommer XP807.  KM1E wrote a nice article 
> in the Dx magazine about selecting one antenna for 20 to 10 including the
> WARC bands.  I ran into him comparing the Sommer to the nice 4el that KA1PE 
> uses on 17.  Compared nicely on short skip and FK8CP said they were the same 
> at his QTH except KM1E faded a bit more.
> I think any of the above and perhaps the big Fritzels are all very close.  I 
> would say don't spend too much time comparing...get one and get on the air. 
> An advocate of "GAD"...Go and do it! 
> Dave K4JRB
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