measures wrote:
>>The SWR in a 50 Ohm system then is 1:1. In a 93 Ohm system
>>you would have the SWR mismatch of 1.86:1,
>
>? Even though there is a half wavelength of 93 ohm coax between the gen.
>and the termination, the system is not 93 ohms. It is 50-ohms at both
>ends of the half wavelength albeit-mismatched transmission line.
Correct. I wrote the statement above yours and in my entire post specified the
system as a 50 Ohm system.
>
>> but in a 50 Ohm system, our
>>VSWR is 1:1.
>>
>? If the termination were changed from 50 to 100-ohms, it would look
>like 100-ohms at the generator and there would be no reflection at the
>halfwave point.
Not exactly, Rich. If the load impedance is 100 Ohms and the transmission line
impedance is 93 Ohms and the source is at 50 Ohms you can't say this.
If the source is 100 Ohms and the load is 100 Ohms, then you are correct.
There would be no reflection.
>
>>So the bottom line is that if you have a 50 Ohm load and a 1/2 wavelength
>>of coax that it matters not what the impedance of that coax is! It's
>>inherently narrow band, but that's the case.
>
>? Agreed. However, above you claimed that the SWR is 1.86:1.
I never did. I always claimed the SWR is 1:1 at the halfwave point in this 50
Ohm system. If I define my characteristic impedance (system impedance) as 93
Ohms, then I do have a 1.86:1 SWR. But your original question revolved around
a 50 Ohm system.
73,
Jon
KE9NA
--------------------------------------------------------------------------
The Second Amendment is NOT about duck hunting!
Jon Ogden
jono@enteract.com
www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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