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Geoffrey S. Mendelson Geoffrey S. Mendelson is offline
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Default Need help - no signal from TV antenna in the attic - Continuity Test?

UCLAN wrote:
It's easy to test coaxial cable, no matter the length. Simply screw on a
75 ohm termination cap at one end, and measure from center conductor to the
ground shield at the other end. The ohmmeter will read 75 ohms plus whatever
the impedance of the cable is.


Actually it won't. The impedance is at RF frequencies, the resistance is
at DC. The DC resistance of coax is close to 0, being the sum of the DC
resistance of the center conductor and the shield.

Resistance meters measure using DC or relatively low frequency AC, it
will be very close to 0.

Geoff.


--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM