Pat, what you are tuning to have a 1:1 SWR is the line between the tuner and
the rig. The line between the tuner and the antenna will have the same SWR
on it whether or not you use a tuner, etc. That line SWR is determined
*only* by the antenna input impedance, the Zo of the line and its loss
(which changes the SWR at the antenna to a lower value at the tuner end).
The SWR indication to trust is the one in the rig. What it is actually
measuring is how close to a 50 ohm resistor your tuner is making the antenna
feedline input impedance look. If an SWR meter placed in the line to the rig
does not agree with the SWR meter in the rig, then the external meter is
probably the culprit. Even a good meter will upset the line impedance enough
to make it and the rig meter read slightly differently.
Again, tune for minimum SWR as shown on the rig's meter. That will be the
right setup.
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"
<mailto:w5yr@att.net>
----- Original Message -----
From: "Patrick Gardella" <pgardella@yahoo.com>
To: <tentec@contesting.com>
Sent: Saturday, June 28, 2003 8:27 PM
Subject: Re: [TenTec] Low power output on Argonaut V
> Sorry, wasn't clear. I can *tune* the feedline to be 1:1. Normally it's
higher than that 1:1 up
> to around 6:1. From the rig to the tuner (bypass dummy load mode), the
tuner shows a SWR of 1:1.
> The rig shows over 2.5:1.
>
> 73
> Patrick N3EO
>
> --- "George, W5YR" <w5yr@att.net> wrote:
> > Patrick, start looking at how and why the SWR in the line from the tuner
to
> > the antenna is 1:1. That cannot be right unless the antenna input
impedance
> > is exactly the same as the Zo of the line. If it were, the tuner would
not
> > be required.
> >
> > Something seems amiss here . . .
> >
> > 73/72, George
> > Amateur Radio W5YR - the Yellow Rose of Texas
> > Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
> > "In the 57th year and it just keeps getting better!"
> > <mailto:w5yr@att.net>
> >
> >
> >
> >
> >
> > ----- Original Message -----
> > From: "Patrick Gardella" <pgardella@yahoo.com>
> > To: <tentec@contesting.com>
> > Sent: Saturday, June 28, 2003 4:03 PM
> > Subject: [TenTec] Low power output on Argonaut V
> >
> >
> > > Need some advice from the guru's out there. Of course, it's Saturday,
and
> > TenTec service is
> > > closed on weekends.
> > >
> > > I've got an Argonaut V. Been using it fine for a while, keeping my
power
> > level around 5W, but I
> > > decided to actually up the power to the max to see what it would do.
I
> > was quite surprised to see
> > > that I could not get more than 14W out of it above 30m! This is both
with
> > the built-in power
> > > meter, as well as an MFJ-949E.
> > >
> > > Something isn't right here. So I checked the SWR was from the rig to
the
> > tuner (since I had a 1:1
> > > from the tuner on out to the antenna). I switched into bypassed dummy
> > load, and keyed up on CW,
> > > with the power set to max (full clockwise). It still showed 14W and
the
> > tuner said 1:1 SWR, which
> > > is what I expected. But when I use the built in SWR meter (key up,
hit
> > the "split" button), it
> > > showed an SWR greater than 2.5:1 (pegged the meter). Trying the
reflected
> > power function ("A-B"
> > > button), it shows a reflected power of around 7W.
> > >
> > > 160m - 18W
> > > 80m - 20W
> > > 40m - 21W
> > > 30m - 20W
> > > 20m - 13W
> > > 17m - 7W
> > > 15m - 12W
> > > 12m - 7W
> > > 10m - 14W
> > >
> > > What's going on here?!? Help!
> > >
> > > 73,
> > > Patrick N3EO
> > >
> > > P.S. I've done a master reset and I'm using firmware 1.70.
> > >
> > > __________________________________
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> >
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>
>
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