[Elecraft] Measuring SWR (Long)

[Don Wilhelm]

For a slightly different answer, take a look at my website www.w3fpr.com 
article on Antennas, Transmission Lines, and Tuners.
You can also find that same article preserved at 
https://www.qsl.net/w3fpr/ant_article.htm.

73,
Don W3FPR

On 4/9/2019 8:56 PM, Don Sanders wrote:
> Since no one has answered your question. I will venture a
> supposition that many know but few will speak out.
> And some still remember their CB days and the erroneous
> advertising saying the power is lost.
> Reflected Power flows back down the feed line and is subjected
> to the normal feed line loss. It then is "reflected" back toward the
> antenna, again subject to the feed line loss, where some of it is
> radiated and some reflected again.
> This continues until the power is dissipated. The book "Reflections"
>   has a very good but somewhat technical explanation.
> Therein also is the reference to forgetting about striving for the
> "Holy Grail" of 1:1 SWR.
> And concentrating on getting it low enough that the transmitter will
> supply full power output. Also using the best low loss feed line and
> proper matching when possible of the feed line to the antenna.
> 
> Dr. Don W4BWS
> 
> God Bless All
> Ham Radio does not make the world go round.
> Ham Radio is what makes the ride worthwhile.
> 
> 
> On Tue, Apr 9, 2019 at 6:43 PM Roy Koeppe <k6xk at ncn.net> wrote:
> 
>> "...Let's allow the reflected power to increase all the way to <gasp> 10
>> watts! At that point, your SWR would be about 2 to 1. Sounds pretty bad,
>> but
>> surely if you were stranded in the desert and had to use your KX3 and a
>> wire
>> to get help, you'd be happy to have a match this good...(etc.)"
>>
>>
>>  From memory now, at 2 to 1...feedline voltage nodes and current nodes can
>> double -- no small thing when power is 1500 watts; can stress antenna
>> system
>> components.
>>
>> 73,   Roy    K6XK
>>
>>
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