A strong signal on 414.0375 MHz was heard by listeners in the northern Broward County area,and was traced to a tower in Palm Beach County. The signal was an analog carrier with no voice or CTCSS tone. The mystery signal continued it's broadcast for 5 days or so, then abruptly left the air.
This frequency is a Federal Interoperability channel, designated as a simplex calling channel. The NTIA designation for this frequency is 4FCAL-45D, previously known as LE-B. The signal was possibly from a base station transmitter that was being installed, or had a problem that kept it keyed up for an extended period.
Keep an ear out for other strange, new signals on the federal 406 MHz to 420 MHz band as the deadline for changes approaches.