Those numbers on cable...

On a recent troubleshooting event, we found that the cables from the public safety and another service provider's antennas were crossed. This created some interesting problems. 


Once we suspected the crossed cable (thanks to Kevin Wysocki), tracing the cables from the roof-top antennas to the head-end equipment became the main challenge - in this particular case, cables from roof-top antennas to lightning protector were all LMR 400, and then from the lightning protector to the equipment were all 1/2" RFS cable. The fact that most of these cables are hidden above the ceiling tiles didn't help either. This is when the numbers printed on the cable comes handy.

You will find strings of alpha numeric texts and numbers on pretty much any kind of cable. Although these are mostly name of cable manufacturer or cable type, model, etc.; one of those numbers (I am calling it Cable Length Indicator) can be very helpful when you are trying to trace cable.  Look at the numbers on each end, subtract to get the legth between the antennas to lightning protector to equipment, and then match the numbers to trace the cables.

This trick can also help during running pair of cable in MIMO applications. However, I still think running 2 separate cable with different colors would make it less confusing.

[Disclaimer: I learned this little trick back in the Nextel days, and recently Scott Wysocki reminded me of its application.]