FAQ: My construction permit only lists an ERP on the horizontal plane. Does this mean that circularly polarized antennas like the Penetrator are illegal?

No. §73.816(a) clearly states that LPFM stations can run antennas that are:

• Horizontal only polarized.
• Vertical only polarized.
• Circularly polarized.
• Ellipitically polarized.

You can not run both a horizontal and vertical polarized antenna.

Therefore, circularly polarized antennas like the Nicom BKG-77 and others of the "penetrator" design are perfectly OK on LPFM either as single bay or multi-bay.