Transmission line calculators 2
My project number 25 from 2010 about transmission lines was originally in Excel format. Now in 2021 I have done here the same with html and Java scripts, which i hope is easier to use.
Coaxial cable
Zo / Ω = 138 * log(D/d) / SQRT(ε)
Give inner diameter D of the outer conductor. D and d in same units.
❶.Give outer diameter d of the inner conductor
❷.Give dielectric constant ε of the media between conductors, for air it is 1.
❸.Cable capacitance [far end open] is: ; C / pF/m = 24.1 * ε / log(D/d)
Cable inductance [far end shorted] is: ; L / μH/m = 0.459 * log(D/d)
Capacitance and inductance valid only, when cable length is much less than a wavelength.
Velicity factor v is: ; v = 1 / SQRT(ε)
Parallel line cable
Zo / Ω = 120 * ACOSH(S/d)
Give wire distance S. S and d in same units.
❶.Give wire diameter d
❷.
Parallel strip-line
Zo / Ω = 377 * a / b , where a much smaller than b.
Give strip distance a. a and b in same units.
❶.Give strip width b
❷.Strip above ground plane
Zo / Ω = 188.4 * a / b , where A much smaller than B.
Give strip distance A. A and B in same units.
❶.Give strip width B, shall be much bigger than A
❷.