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Testing coax


Red Rocket
May 19, 2020
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I lost teh internets two days ago, figured it was my 10 year old modem based on what tech support told me. Just went and swapped it out with the latest and greatest and no dice. When I replaced my septic in late October we knowingly dug through the line, and I spliced a new section in before backfill with the $$$ compression terminals and a heatshrink over the top on each end. I've done it several times before without issue. The coax comes up the side of the house and then splits off in 3 directions. I'm pretty dumb when it comes to this stuff and don't really know how it all works on that level. I'm used to primary distribution cable that can be rung with a jumper between the bleeds and conductor on one end and meter on the other. I assume this is the same if I can find the other end? Is there any way to test the cable to see if I'm getting a "internet signal" from the cable at the house?
I made up a continuity tester years ago when you could buy stuff at radio shack. I would remove the splitter, test to see if you have a short between the two conductors. The tester I made has an audible tone with many adapters built into it like male and female coax, jumpers and phone plug.
Can you log into the modem? If you see a ton of crc errors its a dirty line, likely water intrusion. You can also get a basic coax tester/toner at home debt.

Fully testing coax takes more expensive equipment. It would be cheaper to just get a new cable buried
Yeah just screw the tester on on end and test the resistance on the other end. Then when you find out it's fucked, bury another line. :flipoff2:
Any tech worth their salt will have one of these. https://www.sencoredirect.com/colle.../products/copy-of-sat-catv-tv-signal-analyzer

Maybe flag down your local cable tech and buy them a case of beer for diagnosis?

When I did CATV stuff on the ships, we used the older versions of them.

You can get a "signal analyzer" at a big box store for about $80. It will tell the average homeowner what the problems are.

If you do get a signal tester, you need AT LEAST 8db signal in a 75ohm line for your signal to get through.
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