What can cause Interferance with the Sync signal??


I really need help with this one. I am converting a tower to 900 Mhz sectorized from a 900 Omni. I have installed a Moto CMM and cannot receive sync to my 3 AP’s. The AP’s fully communicate to me over the wire. They tested perfect on the ground and receive sync on a 10ft. cable. When installed on the tower they will not receive sync. The cable length is 265’. Shielded cat5E cable.

Since the units would NOT receive sync I had the climbers pull up new unsheilded cat5 cable to test, still no sync.

Thinking it must be a cable lenth issue I took a partial rolls of cat5E, total length of 342’, put ends on it and tested sync with a AP in the building. Works great. AP’s receives sync as it should. So it’s NOT a cable length issue.

I have reviewed the cable path on the tower. We do NOT cross any power source on the path up the tower to our destination. There must be some other source of interference.

Does anyone have any ideas of what can cause this type of interference or other suggestions. My next process is to physically move the CMM up the tower and run electrical up the tower to the CMM. Not an attractive solution due to the cost. Needs 10 gauge wire to run electrical that distance.

Any help is appreciated.

Thank You!