>From personal experience, I live in Fort Bragg, California (approx 1/4
mile from the ocean) were we get lots of rain, you won't be very happy with
the KLM KT-34XA or A in a wet climate. During the dry months I could count
on a 1.5 to 1 swr on all bands. However, in the fall and winter I would
loose at least ONE band in the rain, not the same band all the time, but
.......
If I wanted a Dummy load, it was great (at 5 or 6 to 1 swr)
I'd be looking for a better tri-bander than the KLM.
Bob Smith
NA6T
At 11:48 PM 6/13/99 -0400, you wrote:
>
>Tower Talk Digest Sunday, June 13 1999 Volume 02 : Number 217
>
>
>
>In this issue:
>
> [TowerTalk] Fw: BOUNCE towertalk@contesting.com: taboo header:
>/^cc:\s*.+/i
> [TowerTalk] Hard Line
> [TowerTalk] ZL-Special
> [TowerTalk] ZL-Special
> Re: [TowerTalk] Force12 C-3 and Omni-VI+ Static Build-up
> [TowerTalk] Channel Master
> Re: [TowerTalk] ZL-Special
> Re: [TowerTalk] ZL-Special
>
>See the end of the digest for information about towertalk-digest
>
>----------------------------------------------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 07:17:52 -0500
>From: "Michael D. Ihry" <mihry@argontech.net>
>Subject: [TowerTalk] Fw: BOUNCE towertalk@contesting.com: taboo header:
>/^cc:\s*.+/i
>
>- ----------
>> From: owner-towertalk@contesting.com
>> To: n5kb@contesting.com
>> Subject: BOUNCE towertalk@contesting.com: taboo header: /^cc:\s*.+/i
To: <towertalk@contesting.com>
>> Date: Saturday, June 12, 1999 6:54 PM
>>
>> >From n5kb Sat Jun 12 19:54:46 1999
>> Received: from hh.tmx.com (hh.tmx.com [207.204.194.1])
>> by contesting.com (8.9.1a/8.9.1) with ESMTP id TAA28325
>> for <towertalk@contesting.com>; Sat, 12 Jun 1999 19:54:45 -0400 (EDT)
>> Received: from localhost (aa6eg@localhost)
>> by hh.tmx.com (8.8.5/8.8.5) with SMTP id QAA06612;
>> Sat, 12 Jun 1999 16:54:38 -0700
To: <towertalk@contesting.com>
>> Date: Sat, 12 Jun 1999 16:54:38 -0700 (PDT)
>> From: Pat Barthelow <aa6eg@hh.tmx.com>
>> To: thompson@mindspring.com
>> cc: towertalk@contesting.com
>> Subject: Re: [TowerTalk] More KT 34XA problems
>> In-Reply-To: <000701beb514$7810e8a0$416256d1@default>
>> Message-ID: <Pine.LNX.3.96.990612164124.6597A-100000@hh.tmx.com>
>> MIME-Version: 1.0
>> Content-Type: TEXT/PLAIN; charset=US-ASCII
>>
>> Hi Dave,
>>
>> We at N6IJ, recently upgraded our KT-34XA with a kit that KLM supplied, I
>> think for about $50.00. We have not erected it yet, so have no SWR data.
>> The new kit also supplied small tubing extensions to install, and bring
>it up to
>> new dimensions shown in the upgrade kit diagrams. It had the newer
>> polyethelyne (blue) end caps for sealing the capacitors, and new
>capacitor
>> tubes that did not have drain holes.
>> They had us drill a small hole on the top side of the inner tube of
>> each capacitor in order to accomplish what the exterior holes formerly
>> did. The inner hole is sealed (mostly) from the immediate outside
>weather,
>> while allowing pressure equalization into the capacitor, which has to
>> occur by the air passageway to the outside,traveling the length of the
>> inner tubes through their open ends some distance away. Apparently the
>> KT-34XA is EXTREMELY sensitive to ANY water entering the tubular
>> capacitors. It is also a real bear to disassemble, clean, repair and
>> weatherseal, though we are looking forward
>> to adding it to our antenna farm and compare with it's bretheren and
>> cousins...
>>
>> 73, DX, de
>> Pat, AA6EG/N6IJ;
>> aa6eg@hh.tmx.com
>> 599 DX Drive, Marina CA 93933
>> "The Contest Station from the Government"
>>
>> On Sat, 12 Jun 1999 thompson@mindspring.com wrote:
>>
>> >
>> > The KT 34 XA has been sitting just above the roof for two months now
>after
>> > completing the re-capping. SWR is below 1.3 on 20 and 10 and 2:1 on
>15.
>> > Never could get 15 below 2:1 and sigs are often louder with the 40
>meter
>> > beam 9 feet above. Looks like interaction.
>> >
>> > But I have been working DX with no problem on 40, 20, 17, 15, 12, and
>10 so
>> > I decided to plan on cranking it all back up for this year. On
>Thursday we
>> > had the first rain fall in three months (over an inch) and I noticed
>the SWR
>> > went up from 1.3 to nearly 3:1 on 10 and SWR crept up some on 15. As
>soon
>> > as the WX dried up the SWR went back down. Does anyone know how to
>keep
>> > the water out of the caps on 10? I have the drain holes down as per
>the
>> > manual and have never had this problem before.
>> >
>> > Dave K4JRB
>> >
>> >
>> >
>> > --
>> > FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>> > Submissions: towertalk@contesting.com
>> > Administrative requests: towertalk-REQUEST@contesting.com
>> > Problems: owner-towertalk@contesting.com
>> > Search: http://www.contesting.com/km9p/search.htm
>> >
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 11:19:02 -0400
>From: jackson@cyberzane.net
>Subject: [TowerTalk] Hard Line
>
>I am looking for about 180-200 ft of
>Andrews 1/2 LDF hard line. Would like new.
>Everett Jackson 1-740-452-7971 WZ8P
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 09:13:14 -0700
>From: "Rod Brink" <rodbrink@montereybay.com>
>Subject: [TowerTalk] ZL-Special
>
>Hi, does anyone know the historical origin of the ZL-Special antenna?
>I have made one out of 300 ohm TV twin-lead and with the matching network I
>came up with, its SWR is 1:1 across the 17 meter band. Am wondering if this
>adaptation has ever been done before and would love to read anything I can
>get my hands on about this antenna.
>
>73, Rod
>KE6RSF
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 11:00:30 -0700
>From: "Rod Brink" <rodbrink@montereybay.com>
>Subject: [TowerTalk] ZL-Special
>
>To Brian Harris who asked about my ZL-Special:
>
>Unfortunately I've recently moved and a lot of my stuff is in storage,
>including my notes on that antenna. However, I'll tell you what I remember.
>The two radiating elements were parallel, half-wave folded dipoles, each
>about 25' 8" long, constructed of 300 ohm TV twinlead. The phasing line
>that interconnected them at their midpoints was 6' 8" long, also twinlead,
>and was given a half-twist. This put the two dipoles about 125 deg out of
>phase from each other and gave the antenna its directionality and
>front-to-back (which was about 18-20db. My modeling software says that by
>playing around a little with the length of the phasing line, its possibly to
>achieve theoretically infinite front-to-back).
>The feedpoint impedance came out to be 35 +j30, as I remember.
>I wound a toroidal 75-to-50 ohm transformer and connected it in parallel
>with a 300 pf mica cap at the feedpoint to transform the 35 ohms to 50 ohms,
>and to cancel out the inductive reactance.
>
>Physically, I suspended the antenna between aluminum conduit pipes 7' long
>at the ends in order to maintain the spacing. Matching network was built
>into small plastic boxes I got at Radio Shack, and partly filled with epoxy
>for water-proofing. I hung it horizontally, like a Yagi, at about 50'. I
>used RG-58 to hang down to the ground to minimize sag, then switched to
>RG-8.
>
>Although it wasn't the classiest looking thing in the world, it was a
>KILLER antenna.
>
>73, Rod
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 14:10:49 -0400
>From: "Guy Olinger, K2AV" <k2av@qsl.net>
>Subject: Re: [TowerTalk] Force12 C-3 and Omni-VI+ Static Build-up
>
>- ----- Original Message -----
>From: Tom Rauch <w8ji@contesting.com>
>To: <W7TS@ibm.net>; <towertalk@contesting.com>; <K7LXC@aol.com>
>Sent: Saturday, June 12, 1999 6:30 AM
>Subject: Re: [TowerTalk] Force12 C-3 and Omni-VI+ Static Build-up
>
>
>>
>> > Why not do the right thing by putting a lightning arrestor like a
>> > Polyphaser at the point where the coax enters the shack connected to a
>> > couple of ground rods? It's not a lightning protection *system* but it
>> > should protect your radio frontend from these static buildups.
>> >
>> > This is probably the easiest option as well since it's at ground
>> > level
>> > and you don't have to fool with the antenna.
>>
>> Polyphaser and other lightning arrestors do almost zero for
>> protecting HF receivers. The problem is they have a breakdown
>> voltage of about a kilovolt, and the receiver has a failure voltage of a
>> few hundred volts or less.
>
>The grounding relays certainly do a lot, at the point where the remote
>switchbox goes. Good first line of defense -- probably enough for a lot of
>induced pulses. They will take care of the static from the antenna. Close
>lightning, however, is a different can of worms.
>
>If one takes a direct hit on the tower, or very close, and the ground
>saturates at the remote switchbox point, then the coax shield, and the
>center conductor by induction, will arrive at the shack with a voltage to
>settle. If the shield is grounded at the house entrance point, that will
>help drain the shield pulse. However, unless the center conductor is also
>grounded at this point, it will carry a differential on to the rig.
>
>If a *DC-blocking* arrestor is used at the house entrance, in addition to
>the ground of the shield, then the rest can be dealt with by a coax switch
>at the rig that grounds the incoming and leaves the HF rig disconnected.
>This, in a thimble summary, is what Polyphaser recommends. It is also a very
>good reason NOT to use a voltage-on-center-conductor type switch .... the DC
>blocking arrestor can't be used.
>
>The switch operating lines to the remote location will also have to receive
>arrestor treatment at the entrance point. These arrestors fire at much lower
>voltage, since you are protecting a 24v circuit, or less, and are a greater
>protection.
>
>*HOWEVER*, even if grounded at the house entrance, a rig-killing
>differential can STILL be present, if the coax house entrance ground is not
>at or directly connected to the power service entrance ground. As the
>lightning pulse spreads out, (we are talking about a period measured in
>microseconds) the ground closest to the strike is at a raised potential to
>the ground farther away. THE GROUND ITSELF will use whatever pathways it
>finds convenient in it's microseconds race to spread out and dissipate.
>
>One unfortunate path of ground potential equalization, since the stuff under
>the house is drier and often laced with less conductive construction debris,
>is this... Read and shudder...
>
>The path of ground equalization comes across the coax shield to the ground
>at the house entrance. Blocked from direct propagation forward by basement
>or less conductive material under the crawlspace, it goes up the shield of
>the coax to the rig(s) and everything tied together by coax of any kind, to
>the green wire connection in the electrical system, and on over to the power
>service entrance ground. The ground equalization DOES go around the house,
>but it takes LONGER to do so. In the time between the arrival of the outer
>equalization around the house and back up the green wire from the power
>ground, lies opportunity for all kinds of odd impedance and distance related
>destructive wierdness. The path through the house is high impedance relative
>to a robust ground bonding, and allows a way for the pulse to build up to
>destructive potentials headed across.
>
>So, for this very short period of time, the *chassis* of your rig can be at
>a high potential above the inner circuitry, and a lot of other things in the
>house, as well, including above both neutral and high leads in the power
>wiring. The rig then gets killed with a *backwards* zap, a very short-lived,
>but very chip-and-transistor-killing-capable backwards zap.
>
>In this circumstance, the common ground has become the enemy, because there
>was not a direct path from the coax entrance ground to the power service
>entrance ground. Depending on exactly how the power wiring physically runs
>inside the house, this could fry TV's, etc, even if the HF rig itself was
>physically disconnected. All there needs to be is a path from the incoming
>shield to something connected to a green wire in the power wiring.
>
>You may say, what about the station ground? Frequently the station ground
>and the coax entrance ground are one and the same, aren't they? In this case
>you don't even need the shield of the coax to create the differential. This
>is NOT to say that you shouldn't have a station ground, just that it needs a
>good, robust bonding to the power service entrance ground, one that is the
>most attractive route to a ground equalization pulse.
>
>The best condition, of course, is that the power entrance, telephone
>entrance, coax entrance, and station ground are all one and the same.
>
>There has been at least one recent TowerTalk post of a rig-frying episode I
>would attribute to a ground equalization differential.
>
>Get the Polyphaser book, understand everything they explain, and do the
>work. Using a grounding switch like the RCS-8V at the remote switch point is
>a good first step, but don't stop there.
>
>73, Guy.
>
>>
>> The solution I use is relays, that automatically disconnect the
>> center conductor. The RCS-8V does this, and the relay shorting
>> bar goes to ground giving excellent protection.
>>
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 14:53:52 EDT
>From: KE4DGI@aol.com
>Subject: [TowerTalk] Channel Master
>
>Hello all,
> I recently purchased a tower that the owner told me was a Channel Master.
>It is a three sided tower like you see advertised in AES catalogue. Does any
>one know where I can find information on this brand?
>
>Thanks
>Tom Drake
>ke4dgi@aol.com
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 17:56:26 -0500
>From: Bob Perring <perring@texas.net>
>Subject: Re: [TowerTalk] ZL-Special
>
>At 11:13 6/13/99 , Rod Brink wrote:
>>Hi, does anyone know the historical origin of the ZL-Special antenna?
>==============================>
>Old CQ or QST back around 1960, or so.
>Bamboo poles and twin lead.
>Made one in 1964 and it worked great.
>N5RP
>
>------------------------------
>
To: <towertalk@contesting.com>
>Date: Sun, 13 Jun 1999 18:00:50 -0500
>From: Bob Perring <perring@texas.net>
>Subject: Re: [TowerTalk] ZL-Special
>
>At 11:13 6/13/99 , Rod Brink wrote:
>>Hi, does anyone know the historical origin of the ZL-Special antenna?
>========================.
>Was the original article called "A Scotsman's Delight" ?
>I believe so.
>A search of CQ or QST under that title might get you the original write
>up.
>N5RP
>
>------------------------------
>
>End of Tower Talk Digest V2 #217
>********************************
>
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-digest-REQUEST@contesting.com
>Problems: owner-towertalk-digest@contesting.com
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
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Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
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