with an SWR of 1.1 to 1 on 20 meters with the ts2000, putting the tuner
inline, though it isn't needed and won't even tune because the swr is
already low enough, will show a power reduction of about 15 watts.
So a 15 percent power reduction with the onboard tuner in is quite
substantial.
unfortunately I didn't have the tw1 when i had the ts570, so i can't compare
the two.
I suspect that a good quality outboard auto, or even manual tuner wouldn't
have this much effect on power output.
73
Colin, V A6BKX
----- Original Message -----
From: "John Miller" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, December 23, 2007 11:16 AM
Subject: Re: possible problem with output power on IC746
> Key the mic on CW as well, it will work. that seems strange though if it
> showed high power before. Hopefully there's nothing going wrong. If you
have
> the tuner in the radio on, turn that off and see if that changes things. I
> haven't checked on the TS-2000 yet but I know my 570, the tuner can cut
the
> power back a bit. Not that much, but it's something to check anyway.
> ----- Original Message -----
> From: "T Behler" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, December 23, 2007 1:12 PM
> Subject: possible problem with output power on IC746
>
>
> > Hello all.
> >
> > I've developed a strange problem with my Icom 746 transceiver, that I
> > could
> > use some help with.
> >
> > I have noticed that, when using my talking SWR meter unit, I only seem
to
> > get about 60% output power with an antenna that is resonant on 3.7 MHZ
and
> > which has a 1.1 to 1 SWR reading.
> >
> > Thinking that something might be wrong with my talking SWR meter, I had
my
> > sighted XYL help me do some checking without the talking SWR meter,
using
> > the meter on the front of the radio.
> >
> > She helped me check the output power meter on the IC746 itself by
> > completely disconnecting the talking SWR meter, and then doing the
> > test.
> >
> > She tells me that, on the bottom scale of the meter, the SWR reading for
> > my
> > resonant 80-meter dipole is indeed 1.1 to 1, which is just what I'd
expect
> > it to be. However, the power output percentage is only around 60% when
> > the
> > RF
> > power knob is turned all the way to the right.
> >
> > I'm doing these tests in both CW and RTTY modes.
> >
> > When I do the test in RTTY mode, I simply use the PTT on the mic. When
> > doing the test in CW mode, I simply have my paddles send a series of
> > "dahs".
> >
> > Could I have something set wrong with the 746, or is there something
wrong
> > with the rig itself?
> >
> > Is there something else I should try?
> >
> > I think I'll go play with my new TS480 now. (grin)
> >
> > 73 from Tom Behler: KB8TYJ
> >
>
>
>
> --
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>
>
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