I am not sure if you took the traps apart from your comments. You should
clean them up inside the cover, make sure the screws at the ends of the
coils are tight and not rusty. The screw that grounds the trap cover is
important too, as the capacitance between that cover and the winding is part
of the tuned circuit. I used to measure the impedance between the ungrounded
end of the trap cover and the element, with my Autek RF Analyst, and if both
were not the same I knew something was wrong with one or the other.
Telescoping elements can make poor contact too, especially if you didnt use
noalox or penetrox or the like. Clean them up with fine steel wool and use
noalox available at Home Depot. 73 JACK W1WEF---- Original Message -----
From: <towertalk-request@contesting.com>
To: <towertalk@contesting.com>
Sent: Tuesday, August 31, 2004 9:33 PM
Subject: TowerTalk Digest, Vol 20, Issue 100
> Send TowerTalk mailing list submissions to
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>
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> or, via email, send a message with subject or body 'help' to
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>
>
> Today's Topics:
>
> 1. Checking / Testing traps?? (Mike Bragassa)
> 2. RE: snow static, Quad v. Yagi (David Robbins K1TTT)
> 3. Re: Quad vs SteppIR (Joe Giacobello)
> 4. Re: Rohn Tower Deliveries (W3YY)
> 5. Quads vs. SteppIR (RICHARD BOYD)
> 6. Re: snow static, Quad v. Yagi (Tom Rauch)
> 7. Re: snow static, Quad v. Yagi (Tom Rauch)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 31 Aug 2004 19:04:49 -0500
> From: "Mike Bragassa" <bragassa@consolidated.net>
> Subject: [TowerTalk] Checking / Testing traps??
> To: <towertalk@contesting.com>
> Message-ID: <004d01c48fb7$4cd57060$6400a8c0@DHFS7541>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Re: HyGain TH-7DX, tribander
>
> I have an old TH-7DX that I am refurbishing. Everything has been cleaned
up and now I have it mounted about 12 feet up the side of a tower...for
testing. I recall having a problem on 10m and want to check out those traps
before I do anything else with the antennae, whether it be sold or used.
>
> I have several questions relating to checking and tuning this antennae: If
anyone can offer guidance; pick-off/merge the answers or comments.
>
> 1. How do you check an antennae with traps? Yes, I know the regular way.
But if there is a problem how can you pinpoint the Pb.
>
> Parameters, so far, at 12 feet above ground, for adjustment purposes:
>
> I see acceptable VSWR's 15 and 20m, considering the current height above
ground, e.g. 2.5:1.
>
> But, on 10m, I see 3:1+++ VSWR, with no appreciable null above or below
10m. Lowest near-bye VSWR (null) was 27,440mhz with just a 3:1+ VSWR.
>
> 2. Can any of you please tell me something that can be determined from
these measurements? (re: traps)
>
> side note:
> This little jewel is 25 years old and is in immaculate condition. 14 years
in Wyoming/Montana couldn't have hurt it, except for Chinook wind damage
risk, and amazingly, 15 years in the humid/muggy/buggy, et al, South
Texas environment apparently did not hurt it. I had not used any of the
special lubricants between elements, etc, and everything came apart clean
and shiny. The stainless steel nuts and bolts, of course, were in nice
condition. I did oil them a bit before taking them loose to avoid any torque
damage. I recall that every time I moved, I had to replace too many S/S nuts
and bolts damaged from torque or galled threads.
>
> Of course the plastic trap caps and driven element(s) insulators were
trash!
>
> Any help, tips or suggestions would be greatly appreciated !
>
> Mike Bragassa, K5UO
> Conroe, Texas
>
>
>
> ------------------------------
>
> Message: 2
> Date: Wed, 1 Sep 2004 00:12:08 -0000
> From: "David Robbins K1TTT" <k1ttt@arrl.net>
> Subject: RE: [TowerTalk] snow static, Quad v. Yagi
> To: <towertalk@contesting.com>
> Message-ID: <001101c48fb8$524b0860$0800a8c0@k1tttibm>
> Content-Type: text/plain; charset="us-ascii"
>
> Of course the gradient is real, and very measurable... even in clear
> air. Even with no storm around there is a gradient that can be easily
> measured and a current constantly flowing from the ground that can be
> measured. I forget the exact values but the gradient is on the order of
> .1 kv/m and current is couple pA/m^2. When a storm approaches this
> gradient gets much larger 10-20kv/m(? off the top of my head) and causes
> the corona effects seen on towers and buildings and heard in radios.
> When a lightning leader approaches it increases even more until the air
> breaks down and streamers form... a nearby lightning discharge of
> course suddenly reduces the local gradient by neutralizing the pocket of
> charge in the cloud that had formed, at least temporarily. It should be
> noted that even snow clouds can develop quite a charge separation,
> rarely enough to trigger lightning, but often enough to cause corona on
> ground structures. Dust and blowing snow can also create a charge
> gradient by the collisions with the ground and other particles (the same
> mechanism that separates charge in a thunderstorm except there its
> between colliding ice crystals moving up and down). Even the turbulent
> flow of hot dust and gasses from volcanoes can cause enough charge build
> up to cause lightning.
>
> Enough speculation... do some reading:
> http://ae.atmos.uah.edu/AE/abstracts/Latham64a.html
> http://www.avalanche.org/~moonstone/issw%2094'/measurements%20of%20the%2
> 0electric%20field%20gradient%20in%20a%20blizzard.htm
> http://www.spacegrant.montana.edu/Text/SandStorm.html
> http://envsci.rutgers.edu/~veron/LightningNotes.pdf
>
> go google if you want more, there are thousands of them out there along
> similar veins.
>
>
>
> David Robbins K1TTT
> e-mail: mailto:k1ttt@arrl.net
> web: http://www.k1ttt.net
> AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
>
>
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com [mailto:towertalk-
> > bounces@contesting.com] On Behalf Of David Jordan
> > Sent: Tuesday, August 31, 2004 22:25
> > To: jimjarvis@comcast.net
> > Cc: towertalk@contesting.com
> > Subject: Re: [TowerTalk] snow static, Quad v. Yagi
> >
> > Interesting...here is some real world experience that might prove
> useful
> > for this discussion.
> >
> > I was talking to a ham last night about this thread and he is also an
> > avid gas model airplane flyer. He says when he was younger that he
> used
> > to use steel wires for control cables. Those wires were about 60-70ft
> > long. When storms were approaching he noticed that flying the plane at
> > four or five feet above the ground was no problem but when he took the
> > plane up to 50-60ft to perform loops, etc., a charge would build up on
> > the pair of wires and zapp the pilot operator's hand. SO, perhaps
> this
> > is another practical proof that the gradient is real and measurable
> (?)!
> >
> > 73,
> > dave
> > wa3gin
> >
> > jimjarvis@comcast.net wrote:
> > > Having just spent time explaining to a guy named Yagi that his name
> was
> > famous, I had two hours on trains to ponder the snow static thing.
> > > Because the quad avoids the corona problems of the yagi and lpda at
> high
> > power and high altitudes, it is not unreasonable to think that that
> same
> > attribute of the closed loop would also reduce snow and rain induced
> > static at lower power levels. Let me append a question mark to
> > that...I'd be interested in thoughts.
> > > I don't buy the "radome" effect notion, though. I'm not made of
> > aluminum, but I can build up a lot of charge walking across a carpet
> in
> > New Mexico, and have an ESD event spanning close to an inch. (> 1
> mile
> > above sea level). Eventually, any charge buildup on the structure
> due to
> > moving snow or rain particles will have to be drained off.
> > > When that happens, what's the current path? Down the conductors to
> the
> > spool holding the BeCu tapes? Is that grounded? IF it's grounded,
> then
> > it may bleed off continuously, as it would for plummer's delight
> yagis,
> > with grounded elements. Somebody might want to ask the Mertel's. I'm
> > sure they'll tell you.
> > > Which brings me to a corollary question...has anyone had first-hand
> > comparison abilities between plummer's delight monobanders, and an
> array
> > with floating elements, like a kt34a, for example? I'd be interested
> in
> > the snow/rain static answer if so.
> > > I've heard the differences in snow static on tall arrays...where the
> > higher antenna has been much noisier than the lower ones. Pretty
> sure
> > that's true, although I'd like to see a theory as to why.
> > > OK...so much for questions from Tokyo. Gotta get some bfst and go
> to
> > work.
> > > N2EA
> > > _______________________________________________
> > >
> > > 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@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@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
> ------------------------------
>
> Message: 3
> Date: Tue, 31 Aug 2004 20:32:18 -0400
> From: Joe Giacobello <k2xx@swva.net>
> Subject: Re: [TowerTalk] Quad vs SteppIR
> To: "Richard (Rick) Karlquist (N6RK)" <richard@karlquist.com>
> Cc: towertalk@contesting.com, Bill Ogden <ogden@us.ibm.com>,
> ABowenN4OO <abowen@nettally.com>, SteppIR@yahoogroups.com
> Message-ID: <41351892.8010409@swva.net>
> Content-Type: text/plain; charset=us-ascii; format=flowed
>
> Rick, I'm not sure what you mean by directive, but there's no doubt that
> quads have poorer F/B than Yagis. Quads seem to have a very narrow
> frequency range over which the F/B peaks, but across the rest of the
> band it's at least 10 dB poorer than a Yagi, if not more. Nevertheless,
> I am using a four element, five band quad on a 24 ft. boom, and the
> model shows that forward gain is at least equivalent to a three element
> monoband Yagi on 20M and better on the higher frequency bands where the
> boom length is longer.
>
> I am also not thrilled with the common feed approach that Mike uses.
> Lew McCoy, in his review of LB quads indicated some interactions
> between harmonically related bands, i.e. 10 and 20 meters, but I
> believe that the feed system has been modified since then. I use
> separate feeds for each band via a remote switch and my experiences have
> been excellent. I have to admit that I've not done actual A/B testing
> on quads vs Yagis, but my on the air experiences indicate that they are
> quite competitive.
>
> I use LB parts in my home-brew quads, and they are of excellent quality.
> Mike also gives attentive, personalized service.
>
> Finally, I would say that a multiband quad is an easy way to get the
> equivalent of multiple monoband Yagis on a single, (relatively) simple
> support structure. There's a lot to be said for that.
>
>
> 73, Joe
>
>
>
> Richard (Rick) Karlquist (N6RK) wrote:
>
> >I have a Lightning Bolt quad and a 4 element SteppIR.
> >My experience is the same, the SteppIR is way more
> >directive than the quad. Before the quad, I had a
> >KT34. It was also more directive than the quad.
> >I only got the quad because it covered the WARC bands.
> >
> >Rick N6RK
> >
> >
> >
> >>Subject: [TowerTalk] Quad vs SteppIR
> >>
> >>
> >>I took down my Lightning Bolt quad, which had been on a 70 ft tower for
9
> >>years. I replaced it with the 3 el SteppIR.
> >>
> >>The first thing I noticed on 20M, was that I had to point the antenna in
> >>the direction I wanted to talk instead of just aiming it north
> >>
> >>
> >>
> >>
> >
> >_______________________________________________
> >
> >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@contesting.com
> >http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> >
> >
>
>
>
>
>
> ------------------------------
>
> Message: 4
> Date: Wed, 1 Sep 2004 01:03:05 -0000
> From: "W3YY" <w3yy@cox.net>
> Subject: Re: [TowerTalk] Rohn Tower Deliveries
> To: "TowerTalk List" <towertalk@contesting.com>
> Message-ID: <003b01c48fbf$70041de0$6601a8c0@w3yy>
> Content-Type: text/plain; charset="iso-8859-1"
>
> This is indeed good news and I hope Rohn/Radian can reestablish the
> reputation formerly held by Rohn.
>
> Any observations on the dimensional accuracy and consistency of the new
> products? Do they fit together smoothly and without difficulty? Are they
> straight? Unfortunately, I know many who experienced problems with the
> quality of production leading to the bankruptcy.
>
>
> ----- Original Message -----
> From: <TexasRF@aol.com>
> To: <towertalk@contesting.com>
> Sent: Tuesday, August 31, 2004 7:36 PM
> Subject: [TowerTalk] Rohn Tower Deliveries
>
>
> > I am pleased to report that at long last the Rohn/Radian order has been
> > delivered to Texas Towers.
> >
> > Model 25G was delivered last month and 45G and 55G was delivered today.
> The
> > galvanizing quality is excellent and appears to be very much equal to
the
> > quality of past shipments from Rohn.
> >
> > Most accessories were also delivered, with the notable exception of TB3
> > Thrust Bearings. Apparently the tooling for the bearings was lost in the
> move
> > from Frankfort back to Peoria. I have been unable to get a delivery date
> for the
> > backordered bearings.
> >
> > The 25G shipment from last month is sold out but another delivery is
> > scheduled for mid September. Hopefully the supply of Rohn/Radian items
> will even out
> > with the next delivery and we can truly promise delivery from stock
> again.
> >
> > Please feel free to call 1 800 272 3467 or e-mail
_sales@texastowers.com_
> > (mailto:sales@texastowers.com) to check on availability and/or pricing
> of
> > Rohn/Radian products.
> >
> > Thanks/73,
> > Gerald Williamson, K5GW, General Manager/Texas Towers
> > _______________________________________________
> >
> > 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@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
>
>
>
>
> ------------------------------
>
> Message: 5
> Date: Tue, 31 Aug 2004 21:07:33 -0400
> From: "RICHARD BOYD" <ke3q@msn.com>
> Subject: [TowerTalk] Quads vs. SteppIR
> To: "towertalk reflector" <towertalk@contesting.com>
> Message-ID: <BAY4-DAV30UjUwJ9SUO0001c0ad@hotmail.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> One or more people have mentioned their "quad" was not as directive as
their
> SteppIR.
> Since they did not mention how many elements their quad was, I assume it
was
> a 2-element,
> in which case it's not surprising it didn't have great directivity. 73 -
> Rich, KE3Q
>
>
> ------------------------------
>
> Message: 6
> Date: Tue, 31 Aug 2004 21:25:05 -0400
> From: "Tom Rauch" <w8ji@contesting.com>
> Subject: Re: [TowerTalk] snow static, Quad v. Yagi
> To: <jimjarvis@comcast.net>, <towertalk@contesting.com>
> Message-ID: <005101c48fc2$83579900$6601a8c0@akorn.net>
> Content-Type: text/plain; charset="iso-8859-1"
>
> > Because the quad avoids the corona problems of the yagi
> and lpda at high power and high altitudes, it is not
> unreasonable to think that that same attribute of the closed
> loop would also reduce snow and rain induced static at lower
> power levels. Let me append a question mark to that...I'd
> be interested in thoughts.>>
>
> That's right. Whats good for corona on transmitting is often
> good for receiving.
>
> > I don't buy the "radome" effect notion, though. I'm not
> made of aluminum, but I can build up a lot
>
> Take your hand and grap a spark plug wire. Now tough that
> same wire with a non-metalic chunk of fiberglass several
> inches or more long. Which passes the most charge through to
> your shoes and the ground?
>
> <<of charge walking across a carpet in New Mexico, and have
> an ESD event spanning close to an inch. (> 1 mile above sea
> level). Eventually, any charge buildup on the structure
> due to moving snow or rain particles will have to be drained
> off. >>
>
> Why would it last until it hit the upper antenna, and then
> in 1% more distance vanish? Is that suddenly diminishing
> charge idea reasonable? I don't think so.
>
> Also we are stuck with the problem that rain, snow, and dust
> sound the same. None actually have to be incontact with the
> antenna to have the noise, and the particle contact rate
> does not track the amount of noise or the pitch of noise.
>
> >> Which brings me to a corollary question...has anyone had
> first-hand comparison abilities between plummer's delight
> monobanders, and an array with floating elements, like a
> kt34a, for example? I'd be interested in the snow/rain
> static answer if so.
>
> All of my grounded element Yagis were every bit as bad as
> insulated element Yagis, but every antenna also has driven
> elements that are grounded. Why would it make any
> dofference if the director or reflector was excited with
> noise, when the element with dorect coupling to the feedline
> is always grounded?
>
> The only thing that can possibly make a difference is if a
> blunt edge was the target rater than a point that protrudes
> outward a larger distance. Same thing that makes a quad less
> likely to have corona while transmitting works OK in this
> case.
>
> Say hi to Yagisan.
>
> 73 Tom
>
>
>
>
> ------------------------------
>
> Message: 7
> Date: Tue, 31 Aug 2004 21:29:55 -0400
> From: "Tom Rauch" <w8ji@contesting.com>
> Subject: Re: [TowerTalk] snow static, Quad v. Yagi
> To: "David Jordan" <wa3gin@erols.com>, <jimjarvis@comcast.net>
> Cc: towertalk@contesting.com
> Message-ID: <005e01c48fc3$30014200$6601a8c0@akorn.net>
> Content-Type: text/plain; charset="iso-8859-1"
>
> > I was talking to a ham last night about this thread and he
> is also an
> > avid gas model airplane flyer. He says when he was
> younger that he used
> > to use steel wires for control cables. Those wires were
> about 60-70ft
> > long. When storms were approaching he noticed that flying
> the plane at
> > four or five feet above the ground was no problem but when
> he took the
> > plane up to 50-60ft to perform loops, etc., a charge would
> build up on
> > the pair of wires and zapp the pilot operator's hand. SO,
> perhaps this
> > is another practical proof that the gradient is real and
> measurable (?)!
>
> That's very true. My 300 ft high 160 dipole will charge
> enough to knock me on my butt in a slight breeze on a dry
> day!
>
> Not so with low antennas, no matter how long they are.
>
> Another good reason why high antennas have more corona in
> bad wx than low antennas. I'm getting a taste for Mexican
> beer.
>
> 73 Tom
>
>
>
>
> ------------------------------
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> End of TowerTalk Digest, Vol 20, Issue 100
> ******************************************
>
_______________________________________________
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
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