[600MRG] From the UTC front page

[lstoskopf at cox.net]

"Electric utilities are allowed to use power line carrier (PLC) transmitters and receivers for control signals and information transmission in the 10-490 kHz band without obtaining a license from the Federal Communication Commission (FCC). However, PLC users are not protected from interference from licensed radio transmitters."

So the FCC HASadded protection.  From the power line company security standpoint, good luck getting them to tell you what frequency they are using.

Still looking for a map of which lines use PLC.

N0UU