Because:
The swr might read 2:1 and the Jupiter could be seeing 25 ohms and a high
reactance. To force 100w out, you may need to consume 300w input. Your
finals are now passing 25 or more amps of current on peaks. You final's
linearity is way out of spec and your rig gets hot. RFI could develope
which could cause strange processor behavior and actually shorten the
life of sensitive chips. Your low pass filters no longer function
properly so you may radiate harmonics and other spurs and your reception
can be degraded by BCI.
Not only this but how can you tell you are really getting 100w out if
your wattmeter only works properly at 50 ohms resistive?
On the positive side:
Er....is there one?
Steve N4LQ
-----Original Message-----
From: Duane A Calvin <ac5aa@juno.com>
To: justo@maplenet.net
To: <tentec@contesting.com>
Date: Wed, 1 May 2002 11:39:51 -0500
Subject: Re: [TenTec] Customer Requests for a Jupiter Wish List
> Why? Having the tuner inline when it's not really needed is just
> adding
> loss. Since the TT amps have no problem driving 100w output into SWR's
> of 2:1 or less, why incur power loss in the matching circuit?
>
> 73, Duane
>
>
> On Wed, 1 May 2002 08:43:10 -0500 "j" <justo@maplenet.net> writes:
> > ----- Original Message -----
> > From: "Rob Atkinson, K5UJ" <k5uj@hotmail.com>
> > >
> > > >have the AT-11MP find a match and then have the TT's 'Tune'
> > feature
> > > > >automatically shut off when a less than 1.5:1 match is
> > reached.
> > >
> > > A programmer taking you at your word on this will program the
> > radio to
> > stop
> > > tx and tuner adjustments at a match of 1.49:1 and not bother to
> > try to
> > find
> > > a 1:1 match. Don't you want the radio to find the best match
> > possible
> > > before quitting? Admittedly there's not much practical difference
> > between
> > 1
> > > and 1.5 however.
> > >
> > > Rob Atkinson
> > > K5UJ
> > > k5uj@hotmail.com
> > >
> >
> >
> > rob,
> >
> > that's a good point. i'll make the correction.
> >
> > thanks to all for your input so far. i'll give it a few days to
> > catch
> > anyone else's ideas.
> >
> > 73,
> > j
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>
> Duane Calvin, AC5AA
> Austin, Texas
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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