Sync Problem

I am trying to convert one tower from a Omni 900 AP to (3) 900 AP’s with 120 deg MTI antennas. I installed a CTM1 timing module first to provide sync. The AP’s would not recieve sync. So I replace the CTM1 with a Moto CMM Micro. The GPS on the CMM all looks good, but the AP’s still will not receive sync. They are all set to receive sync over the power port and if I connect a spare AP to the CMM on the ground it works great. The cable distance is only 265’ from the CMM to the AP, well within the 328’ spec.

This should work! Questions: Were are you guys installing your CMM’s? On the Tower closer to the AP’s or at the bottom? The cable we use is Belden 1300A outdoor cable with sheilding.

We operate a CMM at another tower but it’s a roof mounted tower with our CMM in the attic. Cable distance is only 100’ max.

Is there a shorter distance limitation for the cable run if you have passing sync?

Initially, I thought we must have (3) bad AP’s. Unlikely but possible, so we climbed the tower and replace 1 AP with a fully tested unit. Same results.

Any suggestions, would be appreciated.

are you passing other strong RF sources on your way up the tower? tv signals / radio signals / paging transmitters?

I know we’re running sync from a CMM Micro up to a 900 omni and a 5.7 omni … the 5.7 is at 170 feet and the 900 omni is at 190 feet. The tower is only 190 feet. Our sync is working fine - you’re a little longer than us.

Jay Fuller
Cyber Broadband
Cullman Alabama


No interferance. We are rural area with nothing else on this tower and no other towers around. I spoke with Moto Tech support, we checked all settings - good. They seem to think it must be the cable. I can’t disagree at this point. Seems strange the AP’s are fully operational just can’t receive sync.


Are you going thru the Moto surg protection? if so try by passing it

No Surge protection in place. Cables are direct from the AP’s to the CMM.