Thanks for that link...very interesting.

I am looking at Chart 11480 which I downloaded a few years ago into Open CPN... it shows these towers as Tower (Lighted) HORN. I found in the Local Notice to Mariners for this chart that in August 2013 they changed the label to Tower HORN.... so it appears that they are now unlighted. That seems totally bizarre to me. It would cost next to nothing to keep them lighted. Anyway.... lesson is to keep charts updated.

Thanks for the information.