On Fri, 2008-07-04 at 08:24 -1000, Ken Brown wrote:
>
> > Found this nice table. Thought I would pass it along.
> > http://www.firestik.com/Tech_Docs/SWRLOSS.htm
> >
> >
> >
> "SWR (Standing Wave Ratio) affects the power output of your radio. The
> following table shows the effect of SWR for a transmitter with 4 watts
> of transmitted power."
>
> Using a standard power level of 4 watts, they are not talking to the
> amateur QRP crowd, because those guys generally consider 5 watts to be
> the regular QRP level. Who do you suppose this chart was made for?
> Apparently for people who want some simple (not necessarily accurate)
> explanation of why they should care about SWR, without the complications
> of transmission line loss included. A quick truncation of the url to
> find the home page reveals who their audience is.
>
> Checking a couple of values on this table, it appears the assumption is
> that all of the reflected power just gets dissipated at the transmitter
> and does not get reflected back towards the antenna.
But the data presented is just plain wrong except for the 1:1 case. All
the rest is trash. Its the same quality data as CB antenna gain claims.
> Just a single
> reflection at the mismatch, and the reflected power is lost, that's it!
> If there was a real good circulator (isolator) at the transmitter, that
> would be nearly true.
>
> DE N6KB
>
73, Jerry, K0CQ
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