Yep, you're right, Mike! I realized right after I hit the "send" key that
the return loss improvement is 2x the cable loss...
And a 6dB return loss improvement will take a 3:1 VSWR right down to close
to perfect!
-WB2WIK/6
"If everything seems under control, you're just not going fast enough." -
Mario Andretti
> -----Original Message-----
> From: Mike Gilmer, N2MG [SMTP:n2mg@eham.net]
> Sent: Wednesday, October 02, 2002 10:34 AM
> To: towertalk@contesting.com
> Subject: [Towertalk] 40 meter yagi matching
>
> The return loss improvement caused by cable attenuation will be twice
> the one-way cable loss, in this example: 4.9dB. That's enough to make
> an "infinite" SWR (at the load/antenna) look like 3.5:1 (in the shack),
> or 3.5:1 look like 2.0:1, etc.
>
> Mike N2MG
>
>
> WB2WIK wrote:
>
> > You'll note Bury Flex, like any other .500" or smaller 50 Ohm cable,
> > has attenuation that remains about constant below 10 MHz, and it's
> > about 0.7 dB/100' best case. 350' would be 2.45dB. That improves
> > return loss by 2.45dB, and VSWR measurements will be 2.45dB better
> > than "actual." That's quite an improvement!
>
>
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