I wonder how the "short / open" method compares using Zc = SQRT [L / C] ?
Of course, that will introduce losses due to theoretical infinite SWR.
Dave - W?LEV
On Fri, Apr 4, 2025 at 2:37?PM Team-SIM SIM-Mode via groups.io <sim31_team=
[email protected]> wrote:
Hi
below what i have measured on smith graph with my 25m length of RG213
coax cable with a NanoVNA H4
With Dislord function and no terminaison : it gives Z0=51.7 Ohm , it do
not change with frequency's , based on low frequncy's measurement < 1.7 Mhz
with a 50.3 ohm resistor Coax terminaison, Smith graph gives a nice
centered little circle for 53 Ohm renormalized impedance graph, ( 52 Ohm
and 54 Ohm gives sheefted circles of center ) , 53 Ohm seems to be the
good Z0 value for around 14.100 Mhz frequency's and not 51.7 Ohm as
calculated by Dislord function,
This nice and relatively more accurate method need a 6X Zoom on smith
graph , why not to add this option on the future H4 firmware ?
see sceenshoots attached
73's Nizar
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*Dave - W?LEV*
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Dave - W?LEV
