I'll explain the cryptic title in a moment. We're using MikroTik Cubes to form a studio-to-transmitter link for our community radio station. Analog audio is fed into a Barix Instreamer at the studio which converts it to a digital stream which is fed to the Cube on the roof, which in turn beams to the transmitter site across a parking lot. On that side, the process is reversed and analog audio is fed to the transmitter. At the studio we're using a simple router that manages connections, but is not connected to an outside network.

The MikroTik units have been like absolute rocks, working 24/7, even through hurricane force winds! Last week, though, we lost audio to the transmitter. I could log into the studio-side Cube without problem, and could "see" and log into the transmitter-side unit. Signal strengths were solid.

But, when I went to the transmitter, I could not log into its Cube. Apparently the POE unit was functioning, but there was no data passing through and I could not see (or ping) either of the Barix units. It's like we have a bridge, but it's half a bridge!

I'm an audio guy stumbling my way through IT stuff (not to mention, I'm an old dude so climbing on rooftops is literally a pain). My thoughts on troubleshooting: maybe the Ethernet cable to the roof at the transmitter has a fault whereby POE passes, but data doesn't. Or, maybe there's something wacky about the router. I would welcome some additional thoughts; Monday I'll haul my aging carcass to the roof of the transmitter building to "ring out" the Ethernet cable.