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[email protected] September 26th 06 07:49 PM

Cable Ohm Question
 
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.

Thanks
Brian


Brian Hill September 26th 06 08:56 PM

Cable Ohm Question
 

wrote in message
oups.com...
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.

Thanks
Brian


Wikipedia is your freind Brian :)

http://en.wikipedia.org/wiki/Coax




William Mcfadden September 27th 06 12:07 AM

Cable Ohm Question
 
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.

[email protected] September 27th 06 01:01 AM

Cable Ohm Question
 
Bool Poosey,, I have to watch Death of a Cyclist flick on ''Electric
Ice'' Radio TB now.
cuhulin


[email protected] September 27th 06 02:08 AM

Cable Ohm Question
 
Climbe up the ladder and wait for me!!!! Wallace Beery in that old
movie.

Bungalow Hotel in Vinh Long,Vietnam in 1964 didn't have a stairway up to
the second floor.I once climbed up that ladder,, if y'all get me driff?
www.devilfinder.com Bungalow Hotel Vinh Long Vietnam

Watch m II come along and say I raped that woman in Vinh Long.
I did not,,, she gave it to me for free.
cuhulin,not a rapist


[email protected] September 27th 06 02:10 AM

Cable Ohm Question
 
I gave her five dollars,,, that was big money back in those days.
cuhulin


amyotte September 27th 06 03:11 AM

Cable Ohm Question
 
What the H E double hockey stick are you talkin' about?

I want some of whatever you are having.

Brian

wrote in message
...
I gave her five dollars,,, that was big money back in those days.
cuhulin




--
Posted via a free Usenet account from http://www.teranews.com


[email protected] September 27th 06 03:23 AM

Cable Ohm Question
 
Brian isn (move doggy) cracy.
cuhulin


[email protected] September 27th 06 03:33 AM

Cable Ohm Question
 
Bool sheet,,, doggy hasme figgers loccked ozy,Thang God I am not thhat
crazy#
cuhulin


Telamon September 27th 06 05:48 AM

Cable Ohm Question
 
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


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