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UCLAN UCLAN is offline
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Default Need help - no signal from TV antenna in the attic - ContinuityTest?

Geoffrey S. Mendelson 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.


The OP's report of NO signal present is more indicative of an open rather
than a high impedance at some RF frequency

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


Not with the 75 ohm terminating cap. It will be at least 75 ohms unless
there is a short somewhere in parallel with the 75 ohms.