• jqubed@lemmy.world
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    13 hours ago

    Coaxial cable can come in different sizes, somewhat related to how strong the signal you want to carry is. First time I was in a TV transmitter I saw a lot of copper pipes running across the ceiling, maybe 6 inches (15 cm) in diameter. I asked what the pipes were for and was told they weren’t pipes, they were coaxial cables. Turns out when you need to carry 30,000 watts of RF the cable needs to get a little bigger. Still 75 ohms resistance!

      • jqubed@lemmy.world
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        8 hours ago

        Yes, just that it was being used as a GIANT cable. The inner piece was about an inch (2.5 cm) diameter pipe carrying the signal, and the outer pipe acted as the shield, with plastic spacers to keep the inner piece aligned.