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are you sure the impedance is not showing to be changing with coax length using the 100ohm resistor and 50ohm coax?

afaik whenever the load does not match the characteristic impedance of the coax with any impedance coax the impedance looking into the coax should change with coax length,

when the load matches the characteristic impedance of the coax and x=0 you have no reflections so no standing waves in the coax,
no standing waves gives a constant impedance along the coax,

when the load does not match the coax, standing waves cause impedance to swing about as you move along the coax mirroring the load @ electrical 1/2wave points and inverting the load @ odd 1/4wave multiples,

here is what mfj say,

"If the line is a 50 ohm line, has no radiation or parallel currents, and if the line has minimal loss, moving the analyzer to another point on the line will NOT change SWR reading. Impedance and resonant frequency might change from line transformation effects, but the SWR will not change"

<blockquote data-quote="bob85" data-source="post: 434441" data-attributes="member: 18">are you sure the impedance is not showing to be changing with coax length using the 100ohm resistor and 50ohm coax? afaik&nbsp; whenever the load does not match the characteristic impedance of the coax with any impedance&nbsp; coax the impedance looking into the coax should change with coax length,when the load matches the characteristic impedance of the coax and x=0 you have no reflections so no standing waves in the coax,no standing waves gives a constant impedance along the coax,when&nbsp; the load does not match the coax, standing waves cause impedance to&nbsp; swing about as you move along the coax mirroring the load @ electrical&nbsp; 1/2wave points and inverting the load @ odd 1/4wave multiples,here is what mfj say,&quot;If the line is a 50 ohm line, has no radiation or parallel currents, and if the line has minimal loss, moving the analyzer to another point on the line will NOT change SWR reading. Impedance and resonant frequency might change from line transformation effects, but the SWR will not change&quot;</blockquote>

[QUOTE="bob85, post: 434441, member: 18"] are you sure the impedance is not showing to be changing with coax length using the 100ohm resistor and 50ohm coax? afaik whenever the load does not match the characteristic impedance of the coax with any impedance coax the impedance looking into the coax should change with coax length, when the load matches the characteristic impedance of the coax and x=0 you have no reflections so no standing waves in the coax, no standing waves gives a constant impedance along the coax, when the load does not match the coax, standing waves cause impedance to swing about as you move along the coax mirroring the load @ electrical 1/2wave points and inverting the load @ odd 1/4wave multiples, here is what mfj say, "If the line is a 50 ohm line, has no radiation or parallel currents, and if the line has minimal loss, moving the analyzer to another point on the line will NOT change SWR reading. Impedance and resonant frequency might change from line transformation effects, but the SWR will not change" [/QUOTE]

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