[AMPS] Feedpoint impedance vs SWR

[Hardy Landskov]

At 03:04 AM 10/03/1999 -0700, measures wrote:
>
>>
>>
>>
>>I think I am understanding well the measured SWR vs impedance along the
>>line question.
>>  
>>My next question is:   Given, say, a 100 ohm resistive antenna impedance
>>(at the antenna terminals) connected to (assumed lossless) 50 ohm coax
>>line, of multiple wavelengths, (producing a 2:1 SWR) What is the most
>>extreme feed point impedance swing in the line and how far down the line 
>>is it?  
>> And how can one compute this mathematically, if one does not have
>>access to a smith chart?
>>
>€  My guess is that a quarter wave 50-ohm line would transform the 
>100-ohms to [100^2 + 50^2]^0.5 =[10k + 2.5k]^0.5 = 111.8-ohms.  However, 
>with a half wavelength of any Z coax, the 100-ohms would not be 
>transformed.  
>
>later, Pat. 
>
>-  Rich..., 805.386.3734, www.vcnet.com/measures.  
>
>

My guess is 25 ohms

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