I have access to a spare run of about 150' 1-1/2" heliax at a repeater site. It goes from the "Radio Room" to the roof. There is no antenna connected to it. I would like to verify if it still any good. Obviously, hooking it up to a TDR would be a preferred method of verification. Next best method probably would be hooking it to a transmitter with a Bird thruline at the transmitter and a Bird termaline at the end on the roof. I could then verify SWR and verify actual transmit loss. Lacking that, I wonder if a megger, which I do have, might be of use? If I were to suspect if the heliax is bad due to moisture incursion, one might be able to see a low resistance path between the center conductor and outer shielding. Has anyone tried this? Is there a spec, or reasonable approximation for insulation resistance center to shield per 100 ft or the like?
73 and Thanks Bernie Parker K5BP
