C
callfm
Guest
After just over a week of co-channel interference to WMKL inflicted by a pirate radio station, the North Miami Beach Police Department promptly took a pirate radio station off of the air this morning. The location was found in about 30 minutes using a field strength meter. The transmitter (RVR) was hidden inside a fabricated box in an elevator service room on the rooftop of a 10 story condo building. The program audio was fed in via a cable modem run in from the outside. A high-end sound card produced a processed stereo signal complete with RDS ID. The box was completely screwed shut, had air vents covered with mesh painted grey and with fans on the inside. Power was stolen directly from a disconnect box. The antenna was a Dominator type antenna fed with about 12 feet of 1/2" coax.
Pictures and coverage map:
http://www.callfm.com/pirates/antenna1.jpg
http://www.callfm.com/pirates/antenna2.jpg
http://www.callfm.com/pirates/piraterack.jpg
http://www.callfm.com/pirates/stealingpower.jpg
http://www.callfm.com/pirates/insidethebox.jpg
http://www.callfm.com/pirates/insidethebox2.jpg
http://www.callfm.com/pirates/insidethebox3.jpg
http://www.callfm.com/pirates/freq.jpg
http://www.callfm.com/pirates/fwd.jpg
http://www.callfm.com/pirates/map.jpg
The FWD power was 946 watts (transmitting on WMKL's co-channel frequency of 91.9 MHz).
Doing the math:
946 watts FWD power: -0.24 dBk
Antenna gain: 3 dB (http://fmbroadcastantenna.com/dominator.html)
Line loss for 12 feet of 1/2 foam coax: 0.1 dB
ERP: 2.66 dBk
ERP: 1.85 kW
HAAT: 39 meters
Pirate station 60 dBu population: 837,793 persons (54 dBu population: 1.62 Million)
WMKL 60 dBu population: 265,422 persons (50kW)
Interference area population: 145,087 persons (or 55% of WMKL's 60 dBu population)
Harmless fun, right? Or is it "free" speech?
Pictures and coverage map:
http://www.callfm.com/pirates/antenna1.jpg
http://www.callfm.com/pirates/antenna2.jpg
http://www.callfm.com/pirates/piraterack.jpg
http://www.callfm.com/pirates/stealingpower.jpg
http://www.callfm.com/pirates/insidethebox.jpg
http://www.callfm.com/pirates/insidethebox2.jpg
http://www.callfm.com/pirates/insidethebox3.jpg
http://www.callfm.com/pirates/freq.jpg
http://www.callfm.com/pirates/fwd.jpg
http://www.callfm.com/pirates/map.jpg
The FWD power was 946 watts (transmitting on WMKL's co-channel frequency of 91.9 MHz).
Doing the math:
946 watts FWD power: -0.24 dBk
Antenna gain: 3 dB (http://fmbroadcastantenna.com/dominator.html)
Line loss for 12 feet of 1/2 foam coax: 0.1 dB
ERP: 2.66 dBk
ERP: 1.85 kW
HAAT: 39 meters
Pirate station 60 dBu population: 837,793 persons (54 dBu population: 1.62 Million)
WMKL 60 dBu population: 265,422 persons (50kW)
Interference area population: 145,087 persons (or 55% of WMKL's 60 dBu population)
Harmless fun, right? Or is it "free" speech?