Part of my network is connected via directed radio dish to the other part. The isolated part then goes down to a router that connects to its LAN.
Some contractors have recently refurbished the electrical and put in a new HVAC system. The Ethernet cable is run on the outside of the building, against the wall, under the roof. I believe it was mounted to the wall the entire length to the roof of the building where the radio is, which is about 50-75 meters.
There is now an electrical conduit all along that wall for the AC and the cable to the radio and another switch in the building the radio is on top of. It is also wrapped around the outside of the conduit and the elbow going into the building before it goes into the wall in that same hole.
Afterwards, the bandwidth over there is about 0.20 mbps download and the normal 15-30 Mbps upload. Before the work was done, it was going at about 15-30 Mbps both ways, with both speeds staying relatively even with each other.
Is the proximity of the cable to the AC conduit and the fact that it is wrapped around the conduit the problem?