开云体育

The "measure cable" function was designed to measure a transmission line
(e.g. length of coax), open at the far end, and give you its characteristic
impedance, loss, and length (length only when you give it the correct
velocity factor for the cable). It does this by finding the 1/4 wave
resonant frequency for the full length of cable, and doing the
calculations, assuming it is a transmission line. If instead you have a
wire antenna at the end, or a multi-wire fan dipole attached at the end,
there may be multiple 1/4 wavelength resonance points - it always chooses
the first, so it will only show you one length. The first one it sees may
be of the length of the coax, or it may be of the coax plus one of your
wires, depending on the design of your system. If you instead use the TDR
function, you may be able to see peaks due to reflections from the
feedpoint and each of the wires, but maybe not: if the antenna is closely
matched in impedance, it won't give much of a reflection to see. I've
never tried that - it may be interesting to see what happens.