No sync from CMM

We currently have a strange issue - we are running 900MHz clusters and CMM Micros and we are using timing over power port. At one site the entire cluster is showing ERROR: No Sync! althought the CMM Micro is showing SYNC OK /3D Fix and tracking approx 7 satellites. After reading similar issues in this forum we have swapped out the CMM Micro and GPS unit but still have the same issue. Is it possible that all 6 APs have failed at the same time? We did have a lightning storm roll through this area recently.

Have you swapped out the cable for the GPS?

Unfortunately the tech that went onsite did not have a spare GPS cable with him. Our next steps are to try a new GPS cable and then a new AP. Just wondering if anyone has any other suggestions?

9 out of the 10 times we’ve had problems with GPS sync it has been a cable issue.

Next time, have the tech pull the GPS antenna and check all connections for any signs of water intrusion. sometimes just clearing out the connects will solve the issue.

We have replaced the GPS Cable and still the same issue. Once we put a replacment AP in place it was recieveing sync immediately. I find it strange that all 6 APs would be damamged in this way, although someone mentioned that this is a known issue with the APs and nearby lightning strikes - something about a capacitor? Has anyone heard of this before?

had the same problem lately with my cmm a 4 ap cluster took a hit but only one wouldn’t sync to the power port so i put in a sync pipe and timed them on the timing port problem solved.

More than likely a cable problem, HOWEVER, I recently had 4 APs and a BH stop receiving sync after a storm and did the whole Sync cable, GPS antenna and line, even replaced the CMM… still the same.

The units had taken a hit and lost lost the ability to recognize the sync pulse through the power port… replaced APs and BH and all is good now…

Learning every day!

CM