Mitch,
What frequency band are you talking about? If it is 10-meters, then 4-feet
of coax can be significant wavelength-wise. But even so, it means your SWR
is not unity, and the four feet is acting as a transformer section. The
effect should be much less pronounced on say, 80-meters??
73, Roy K6XK
-----Original Message-----
From: MitchA@pssch.ps.ge.com <MitchA@pssch.ps.ge.com>
To: tentec@contesting.com <tentec@contesting.com>
To: <tentec@contesting.com>
Date: Monday, January 25, 1999 11:07 AM
Subject: [TenTec] Cable Lengths
>
>Hi, Guys:
>
>I have been rearranging the station over here to fit in some new
equipment -
>actually the 1208A 6m Transverter - and have noticed that the SWR and
>observed power output changes as I add lengths of coax. Now, it is 100' to
>my HF antenna and I have always had about 100W output from the Omni V -- I
>can't see a resistance problem with 4 feet of extra coax (I tried multiple
>pieces). BUT...I do remember listening to a Collins net one time where
they
>were discussing ideal lengths of coax that the factory literature
>recommended in order to yield the best SWR. I also remember learning about
>wavelength and transmission line lengths, back in the dark ages of
>engineering school. Would any of you be able to refresh us on this, as it
>relates to 50-ohm coax, such as RG-213 ? Thank you.
>
>73 --
>
>Mitch KG9DB
>
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