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Telamon · September 27th 06, 05:48 AM posted to rec.radio.shortwave

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?

Just a question that has bugged me for a while.

Coax and twin lead cables are transmission lines so 50 ohm coax, 75 ohm
coax, and 300 ohm twin lead refer to the complex impedance not
resistance. Look up transmission line theory.

You could use a network analyzer or TDR (time domain reflectometry) to
measure transmission line impedance. A DVM only measures resistance at
DC.

--
Telamon
Ventura, California