Interference in Cat5e cable on tower

Why types of symptoms have people run into when getting interference in their cables on a tower?

I’m trying to determine if we are getting some from a newly broadcasting FM station on our tower.


CRC errors

First try running the AP at 10M/HDX and see if things improve.

It’s likely you will need to go with shielded cables and/or conduit and grounding at the top and bottom of the cable run

CRC errors are definately there. Just checked.

We had a nice Moxa switch in the tower for cold weather purposes, but had to switch it out with a cheap d-link to keep the tower alive for the moment. I had to already set the AP to 10FD to get the link to work even for a short while with the MOXA. But it failed, and the dlink for whatever reason has been working for us.

By grounding the shielded cable at the top, how would one do that with a standard Moto AP? Using the the drain wire and connecting that to the tower? Since the AP is a solid plastic, its obviously not going to do it.


Search the forum, there was a procedure for dealing with FM that worked. I think they used SS600’s at the top and bottom but I’m not sure.

You might be able to get away with just using shielded cable, floating it at the top and grounding at the bottom.

Well we reran cable to our Tranzeo backhaul, a new STP line, and re-crimped our AP with new Shielded ends.

At the top of the cable, we didn’t attach the drain cable to anything.

At the bottom, in our ‘hut’ we ran them into Moto Surge surpressors, and attached teh drain wire to the ground in the SS.

We then also made sure to attach the ground to the Moxa switch that we hadn’t in the past, a big no no! :stuck_out_tongue:

All crc errors are gone, running at Auto all, and getting the 100meg full connection. So far so good.

Make sure to ground the Cat5/6 cables on one end to help reduce interference on the cables.

If you are running cables outdoor I always recommend using shielded cable.

There are many PVC cable management products out there for example: there is a product call Pipe Me In. It is a split PVC conduit that allows you run your electrical cable on one side and your data cable on the other. Here is the link to their website