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Subject:
From:
"Dr. Ronald E. Milliman" <[log in to unmask]>
Reply To:
Date:
Mon, 4 May 2015 11:21:17 -0500
Content-Type:
text/plain
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text/plain (145 lines)
Matt, you are getting lots of excellent advice here from your colleagues
concerning your antenna issue. If I understand your configuration correctly,
you are feeding your antenna directly with 450 ohm feedline, which in turn,
comes down into a 4:1 balun, and comes out the other side with a piece of 52
ohm coax
That connects to your transceiver, right?? I assume this is a current balun;
it should be. 

If that is the case, then, you can do two things that is very inexpensive to
do before even considering investing a lot of money in an external tuner.
You can either lengthen your antenna a little by adding some additional wire
of equal lengths to each end of your antenna or secondly, you can adjust
your feedline length. It sounds like your feedline is already quite short,
so, you can add some additional 450 ohm feedline to what you have. Here are
some suggested total feedline lengths that might help you:

34-40, 90-102 or 160-172 feet 

However, as already suggested, before you do anything, it would be a good
idea to write to the source that designed and sells your antenna to get
their recommendations. In your case, I would think purchasing an expensive
external tuner would be your last resort. Of course, if money is no object,
as is the case for some people, then, the external tuner will probably solve
your problem; at least, it will make your transceiver think the problem is
solved! <lol>

Ron, K8HSY

-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Pat Byrne
Sent: Monday, May 04, 2015 9:41 AM
To: [log in to unmask]
Subject: Re: Question about Auto Antenna Tuners

Matt,
I would have concerns about running really high power with your current
configuration.  I looked at the ultralight website yesterday and believe
that I noticed that the balun was rated at 300 watts and the LMR240 coax
might have some limitations.  And, if you run high power you will have to
consider a 220 volt line in to your shack.  Personally i am concerned about
running power - I live on a suburban lot and have neighbors fifty feet
either side of me.  And the more power you run, the more likelihood you have
of causing RFI in yours and other people's consumer equipment.
Don't get me wrong - I'd love to have a bunch of watts available to make
holes in the QRM and QRN, but there are a lot of unintended consequences as
you go down that road.
Good luck with whatever you decide to do.
pat, K9JAUAt 09:17 AM 5/4/2015, you wrote:
>Hi, Alan.  Will the UltraLight Junior along with LMR-240 coax and a
>4-1 balun be up to the task?  Also, unsure if my lightning arrestor can 
>hack the throughput, as it's protection is based on low-medium power?
>
>Also, may consider staying away from those bands during the summer, and 
>goin back to them come fall and winter.  Thanks.--Matt, N1IBB.
>
>At 07:08 AM 5/4/2015 -0700, you wrote:
> >Matt, if you operate any 40 and/or 75 meters during the summer 
> >months, 1500 watts is very important.  I get to suffer thru trying to 
> >copy guys on both bands during summer on various groups, and those 
> >stations running 500 watts or less are next to impossible to hear.  
> >Of course they aren't trying to copy themselves so they have no 
> >direct way of knowing just how painful it is.  When operating the low 
> >bands during the summer, there is no such thing as running too much 
> >power, Hi.  I recommend getting the biggest amp that you can physically
fit in your shack.
> >
> >Alan - N7MIT
> >
> >
> >
> >
> >
> >Alan R. Downing
> >Phoenix, AZ
> >
> >-----Original Message-----
> >From: For blind ham radio operators 
> >[mailto:[log in to unmask]]
> >On Behalf Of Matthew Chao
> >Sent: Monday, May 04, 2015 6:25 AM
> >To: [log in to unmask]
> >Subject: Re: Question about Auto Antenna Tuners
> >
> >Hi, Butch.  Don't plan to get an amp anytime soon; may want to go up 
> >to about 500 watts max in the future, but certainly not 1500.--Matt,
N1IBB.
> >
> >At 11:50 AM 5/3/2015 -0700, you wrote:
> > >There is no way it will be that broad banded.  A sull half wave 
> > >dipole will usually cover about 200 kc of the band between 2 to one 
> > >points.  As far as external tuners, ldg makes a good one, depends 
> > >on how much power you need it to handle.  If you don't have an amp, 
> > >I think around the
> > >$200 or less should get you something that would work.
> > >73
> > >Butch
> > >WA0VJR
> > >Node 3148
> > >Wallace, ks.
> > >
> > >
> > >On Sun, 3 May
> > >2015, Matthew Chao wrote:
> > >
> > > > Hi, butch.  Antenna has an estimated 12-1 SWR at 3.600MHZ, but 
> > > > it drops to 4-1 at 3.8MHZ.  Supposed to work from 80-10 
> > > > meters.--Matt,
> >N1IBB.
> > > >
> > > > At 10:36 AM 5/3/2015 -0700, you wrote:
> > > >> Remember, just because an antenna can be tuned with an etuner 
> > > >> doesn't mean it will radiate well.  I don't know what the swr 
> > > >> limits
> are on the
> > > >> 480, I'm a little surprised it won't tune though.  Where is
> the antenna
> > > >> actually resonant and what is the swr there?
> > > >> 73
> > > >> Butch
> > > >> WA0VJR
> > > >> Node 3148
> > > >> Wallace, ks.
> > > >>
> > > >>
> > > >> On Sun, 3 May 2015, Matthew
> > > >> Chao wrote:
> > > >>
> > > >>> Hi, Folks.  I have a TS480SAT which has a built-in auto tuner.  
> > > >>> Had one of my ham buddies come over and test the setup he and 
> > > >>> his buddies put up, an UltraLight Junior dipole strung between 
> > > >>> two trees and my house.  We noticed that on 3.550MHZ, we were 
> > > >>> getting 4-1 SWr, egen though the antenna can go down that far 
> > > >>> - 80-10 meters.  Above 3.8MHZ, the antenna tunes up.
> > > >>>
> > > >>> My question is:  if I buy an external auto tuner, will I have 
> > > >>> more flexibility in getting a match.  Are the the built-in 
> > > >>> tuners mor limited than the external ones?  And what 
> > > >>> accessible tuner would you recommend if there is a
difference?Thanks in advance.--Matt, N1IBB.
> > > >>>
> > > >>>
> > > >
> > > >

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