I love it when what happened to me and several others
mostly at W3KHW a ham radio club in Pittsburgh is
dismissed as silly nonsensical rubbish. I tried
everything mentioned here to solve the problem:
Twisting. Lengthening and shorting the feed length.
Match boxes. Balun and no balun. Making sure it didn't
touch anything. Making sure it had no sharp bends.
Wrapping it in circles. Straightening it. Name it and
it was tried via advice from all the old timers at
W3KHW. So finally coax was purchased and problem was
solved instantly. This is why I stated ladder line
radiates like crazy because it sure as hell did in my
situation and several others at W3KWH. Call me stupid,
misinformed, insane or whatever does it for you, it
doesn't matter because I know what ladder provided me
and a few others, nothing but nightmares of RFI and
TVI to my neighbors who lived very close to me back
then. The other guys had problems with it getting into
their homes with RF flying around the house causing
family members to complain. I don't care if you have
been using ladder for 60 years! For me and a few of
my friends it was nothing but headaches. Coax on the
extreme other hand was very unforgiving and ?never?
radiated no matter the configuration applied to it
unlike ladder line. Funny how the old timers are the
ones who use ladder line, it's not something that is
wildly popular these days and neither are the big
bands and Frank Sinatra on the top 40 charts anymore,
they are a distant memory. Distance as in light years.
I will no longer respond to this subject because it?s
only vanity going back and forth ad nauseam and for
what? Mine is bigger than yours?.don?t think so.
Love Curt
--- NJ0IP <Rick@DJ0IP.de> wrote:
> I fully agree with Stuart. Curt must have made some
> strange experience to
> cause him to feel that way.
>
> Ladderline does not radiate like crazy - hardly at
> all - if the load at both
> ends are symmetrical. Stuart's tip about twisting
> it is highly recommended.
>
> I've used openwire for over 40 years and the
> ladderline since about 20 years
> now. I have often had cases of it radiating.
> Specifically, nearly every
> time I tried to feed it thru a balun in front of an
> asymmetrical matchbox.
> I don't care which side of the matchbox you place
> the balun, it still did
> not eliminate this radiation - especially when
> running a linear.
>
> I have also had at a truly symmetrical matchbox
> (Annecke) for the past 25
> years and each time I had the problem above, I
> solved it by using my
> symmetrical matchbox instead of the jerry-rigged
> solution described above
> (and still sold by many vendors as "a symmetrical
> solution"). Lesson
> learned. There are no shortcuts in life and quality
> costs money.
>
> In the meantime I have 4 symmetrical matchboxes with
> various power ratings
> and I run legal power here and don't have any
> problems with feedline
> radiation.
>
> Coax radiates too if it has high SWR on it
> (everybody knows that and knows
> how to fix it).
> Open wire feedline radiates when either of its ends
> are not in balance (keep
> it in balance and it won't radiate).
> These are rules of thumb.
> Of course there are rare exceptions to every rule,
> but the statement that
> ladderline radiates like crazy is blatantly wrong!
>
> Using ladderline or homebrew openwire is an
> excellent way to build a simple,
> effective wire antenna which will operate all (or
> most) bands.
>
> If anyone is interested in using openwire /
> ladderline feedline but wasn't
> sure how to feed it, here is some useful
> information:
>
> In the meantime there are good symmetrical
> matchboxes available for all
> sorts of power level. The are at least 5 or 6
> vendors offering excellent
> products for a reasonable price. A recent ARRL
> (QST) article described some
> of these, but only focused on the U.S. vendors (MFJ,
> Palstar). There are
> alse several European vendors with great products
> too (e.g., U.K. Amp,
> Hamware, Christian (DL3LAC), and DL1SWR). Just be
> sure the box you are
> interested in is truly symmetrical. MFJ and Palstar
> both make good and bad
> products advertised as suitable for symmetrical.
>
> 73
> Rick
>
>
> -----Original Message-----
> From: tentec-bounces@contesting.com
> [mailto:tentec-bounces@contesting.com]
> On Behalf Of Curt
> Sent: Friday, July 08, 2005 11:45 AM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] "Radiates like Crazy"???? No
>
> I don't care if you do or don't...you're
> wrong!!!!!!!!!!
>
> --- Stuart Rohre <rohre@arlut.utexas.edu> wrote:
>
> > I must respectfully disagree that ladder line
> > "radiates like crazy".
> >
> > It is BALANCED line, that means if it is fed from
> a
> > balanced source and goes
> > to a balanced antenna, the currents are equal and
> > opposite in each wire and
> > their fields cancel within a few diameters of the
> > line. See the theory of
> > transmission lines in the ARRL Handbooks.
> >
> > It should cross conductors at right angles, and
> > should be twisted every 18
> > inches or so, to minimize effects from nearby
> > conductors that could
> > unbalance it.
> >
> > If you ever have ladder line "radiating" you are
> mis
> > applying it in some way
> > at one end or the other. Balanced antennas are
> > center fed beams, dipoles,
> > etc. with line brought off at 90 degrees to the
> > antenna wires.
> >
> > Let's bury these old wive's tales about balanced
> > parallel transmission
> > lines.
> >
> > Stuart
> > K5KVH
> >
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> >
> http://lists.contesting.com/mailman/listinfo/tentec
> >
>
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