Thanks Jim and the others
My antenna is showing 1:1 SWR levels. When I check the
SWR usinf the radio SWR meter, it is 1:1 if passing
through the linear. Its goes to high levels when I
switch the linear's relay.
It varies. Some times the FT-1000mp can match the
linear input and sometimes not.
Regards
Marcel, EA3IN
--- Jim Dunbar <jdunbar28@mchsi.com> wrote:
> Marcel,
>
> You need to take the Titan 425 out of the line and
> just use the FT-1000MP
> connected to the Ten Meter antenna and with the
> AutoTuner turned off.
>
> Then, what is the SWR on 10 meters with only the
> FT-1000MP without using the
> internal autotuner??
>
> If it is less than 3 : 1 you can turn on the
> internal autotuner and see if
> it takes care of the mismatch.
>
> If the SWR is greater than 2:1 without the
> autotuner, then you are going to
> need an external tuner after the Titan
> amplifier.
>
> When you use the Autotuner going into the Titan 425
> amplifier, all you are
> doing is attempting to match to the input circuit of
> the Titan, however, the
> high SWR that existed previously is still going to
> be between the amplifier
> and the antenna. The autotuner does not take care of
> this problem.
>
> Therefore, you have only two options:
>
> 1. Fix the antenna and feedline so that the SWR is
> less than 2:1 without any
> internal or external tuners.
>
> 2. Use an external Antenna Tuner such as the Ten Tec
> 238 after the Titan
> 425. This will definitely take care of your SWR
> problem between the amp and
> the antenna, however, as I said, if the SWR is
> already greater than 2:1
> on the 10 meter antenna everywhere, then something
> else has happened on your
> antenna or feedine or balun.
>
> So, even is you can use an external tuner for
> matching normal SWR values of
> 3:1 or less, you should further investigate your
> antenna and feedline and
> determine is it is resonant any where in the 10
> meter band, or do you have
> an intermittent condition that causes the SWR to be
> high once in a while,
> such as under a higher power load.
>
> I have seen certain antenna / feedline
> installations, that under higher
> power, something breaks down and the SWR
> will jump up when high power is applied, which is a
> further indication of a
> balun problem or a connector or feedline problem.
>
> So, there is a lot of checking out to do, and you
> need to know that an
> external antenna tuner is being used to match
> a normal antenna VSWR range of 3:1 or less and not
> be used to match to a
> VSWR that is being caused by an antenna, balun,
> feedline, or connector
> problem.
>
> I have an FT-1000D that I use the internal autotuner
> when not using the
> amplifier. When I use the amplifier, I kick in my
> NYE Viking MB-VA Tuner and
> I use it for my Force 12 C31XR on 10, 15, and 20,
> and I also use the tuner
> for both my 40 meter and 80 meter full size delta
> loops. So, it makes a very
> nice addition to the station, so that the amplifier
> is always seeing a 1:1
> VSWR match.
>
> So again, without the amplifier, I use the internal
> autotuner on the
> FT-1000D, and with the amplifier, I turn of the
> autotuner and use the
> external tuner between the amplifier and the
> antenna. This is the best
> option.
>
> And fininally, on areas of the band where the VSWR
> is less than 1.5 to 1, I
> don't have to use either tuner, however, you will
> see a little bit of
> reflected power on the amplifier.
>
> Hope this helps.
>
> Thanks,
>
> Jim Dunbar
> K4PV
> ----- Original Message -----
> From: "Marcel Jorba" <ea3in@yahoo.com>
> To: <tentec@contesting.com>
> Sent: Sunday, October 12, 2003 2:58 AM
> Subject: [TenTec] High SWR on 28 Mhz in Titan 425
>
>
> > Hi!
> >
> > I ask for your help again!
> >
> > My Titan is showing very high SWR to my FT-1000mp
> so
> > it doesn't drives it most of the time. Time to
> time
> > the internal tuner tunes it and I put abt 1KW out,
> but
> > nothing most of the time.
> >
> > I tried with an FT-990 and the SWR is there also
> on
> > 10.
> >
> > Any help?
> >
> > Regards
> >
> > Marcel
> >
> >
> >
> > __________________________________
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