Get an impedance bridge to measure the coax.. A directional coupler will
help. The other way is calculate the impedance based on wire size, spacing,
dielectric, etc,
al

"Dan Jacobson" wrote in message
...
Dear antenna pros, I've always taken it for grunted about the
300/75/50 ohms of TV ribbon, coax, etc. But how does one measure it?
My ohmsmeter doesn't budge. Is there some standard formula, like wrap
grandma 100 times, with the far end connected to a cheeseburger in her
mouth, the near end finally displaying the characteristic 300/75/50
whatever ohmses?