FM broadcast tower and slow links

[dougncbp]

Hello,

We are trying to start service on a new tower. It is a 5KW FM station operating at 94.9MHz. We have shielded cables on all runs now, and are at least 100' below the FM antenna at the top of the tower. The gear is: 1 - UBNT AF5X, 3 - UBNT Rocket M2's, and one MikroTik Dyna Dish 5. The Mikrotik is very low on the tower compared to the UBNT gear, and links up consistently at 1Gbps. We have RF-Armor on the Rockets, and the AF5X just has the part of the Armor covering the radio.

The switch we are using in the hut is the WS-10-250AC. The AF will start out at a Gig, then over time it will drop to 100M FD. Two of the Rockets will try to link up at 100Meg, and will very quickly drop to 10M FD. The other one, which is in the shadow of the AF dish, seems to be holding at 100Meg.

We had them shut off the transmitter for a short while, and in that situation all Ethernet links ran at their maximum advertised speeds. This is clearly a case of RF overload into the AF and Rockets, but since all have RF Armor there's not much more to do. If we lower things even more, it would compromise the AF link and also reduce the number of customers than we can serve.

Anyone else here on an FM tower with that much power?

[sirhc]

This has been a battle fought for many years as Ethernet communications (cables) being susceptible to this freq.

You can search the forums here and at UBNT forums for people suggestions, they range from fiber to metal conduit to Carrier Class cable and magnets.

[dougncbp]

Thanks for the tip. One question regarding the switch status page though... Sometimes it says 100M F and other times you will see two little opposing arrows after the F or H. I just upgraded another switch with an Air Fiber, and it still says 1G, with no arrows. What do the arrows signify?

[sirhc]

Thanks for the tip. One question regarding the switch status page though... Sometimes it says 100M F and other times you will see two little opposing arrows after the F or H. I just upgraded another switch with an Air Fiber, and it still says 1G, with no arrows. What do the arrows signify?

Try moving your mouse over the arrows and reading the pop up info balloon

[dougncbp]

Ah, thanks. For some reason, we had disabled flow control on all ports on the first Netonix switch we employed. So it never showed the arrows.

[sirhc]

Ah, thanks. For some reason, we had disabled flow control on all ports on the first Netonix switch we employed. So it never showed the arrows.

You want Flow Control ON using wireless links.

You want Flow Control all the way back to your router