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Date: | Sat, 6 Aug 2005 10:06:26 -0400 |
Content-Type: | text/plain |
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Hi.
Actually, you have to read the specs on the impedance range that it will
match. What you say is true if you have a low impedance, but if the
impedance is on the high side, it will only match 150 ohms, which will give
you about a 3 to 1 SWR. They did that specifically because mobile antennas
usually have a low impedance, and as Howard indicated with the TS480S, the
tuner is really intended to broaden the range of a mobile antenna.
My point is that many of the external tuners have much better range, and
with the interfaces that are available for Kenwood radios and others,
operating them is almost like having the internal tuner switched in except
that you have an extra box sitting up on the shelf. Actually, it worked
out great for me because the tuner has a antenna switch built in, and that
gives me one more antenna position--just enough that I now have enough
positions for all of my HF antennas plus the 6 meter antenna without having
to fumble with coax connections behind the radio.
73, de Lou K2LKK
P.S. Does anyone have a text manual for the MFJ993? I downloaded the
manual but even with updating Adobe Reader, I had difficulty opening the
file and actually getting anything meaningful out of it.
At 09:28 AM 8/6/2005 -0400, you wrote:
>Not sure about the claims that the TS 2000 autotuner will only handle 3:1
>mismatch.
>
>The manual says 10:1 and any higher than 10:1 you get the swr warning in cw.
>My autotuner will handle 8 or 9 to 1 swr on a shortened 160 dipole when
>tuning in a section of the band away from the resonant point.
>
>For wide mismatches, I use a Palstar manual tuner which is as big as a
>small car and I think has lower losses than the autotuner.
>
>I have found some odd combinations of freq and antenna where the autotuner
>will not tune a 4:1 swr. Adding / removing some coax jumpers to the shack
>end of the coax will usually find a total coax length that makes the
>autotuner happy. Every situation is different, you just have to experiment.
>
>73 Steve KW3A
>
>
>----- Original Message -----
>From: "Ed Malmgren" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Friday, August 05, 2005 6:22 PM
>Subject: Tuners
>
>
> > It is nice to have a tuner with a wide range but remember when dealing
>with
> > big miss matches/high S W R you are loosing a lot of power in heat so it
>is
> > best if you can get the S W R down to begin with. Ed K7UC
> >
> >
> >
Louis Kim Kline
A.R.S. K2LKK
Home e-mail: [log in to unmask]
Work e-mail: [log in to unmask]
Work Telephone: (585) 697-5753
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