In article .com,
wrote:
I am aware of the 50 and 75 ohm coax and the 300 ohm twin lead BUT I am
not sure what this means.
I know about ohms as resistance in resistors but how does that pertain
to cable.
Example - If I have 50 feet of 300 ohm twim lead ribbon cable and 50 ft
of 75 ohm coax could I measure this ohm reading with a meter?
50, 75, and 300 ohms refer to the characteristic impedances of the cables.
In simple terms, impedance can be thought of as AC resistance (an ohmmeter
measures DC resistance).
The length of the cable doesn't affect its characteristic impedance, but it
does affect signal loss. Fortunately, most cables have low loss at
shortwave frequencies.
--
Bill McFadden
http://www.rdrop.com/users/billmc
CAUTION: Don't look into laser beam with remaining eye.