Patrick,
It would seem that your PA transistors are OK as you do get 20 watts or
close to 20 watts on several bands. It sounds like someting is amiss
with your SWR detector circuit. Could you have suffered some damage from
ESD (static discharge) either natural or self made?
On the bands that have low output do you have a way to measure current
drawn by the rig? I'm not sure about the Argonaut V but most T-T rigs
do not have power fold back on high SWR. They depend on current
limiting to protect the PA stage under high SWR conditions. If you have
low output power but higher than normal current being drawn in the PA
then you DO have an SWR problem somewhere. Perhaps from some switching
diodes that have gone bad.
Please keep us posted.
GL & 73,
Bill - K6WLM
Patrick Gardella wrote:
>
> 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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