When Verizon Wireless needed to expand its facilities in Wailuku, Hawaii, the local zoning board said, “No.” That’s not the end of the story.
Verizon responded by looking for an AM partner with an existing tower on which it could colocate its equipment. There’s the happy ending to the story.
Radio station KMVI-AM had a 450-foot-high tower in the perfect location. There was one problem: The structure couldn’t support the Verizon equipment. Happily, that was not a fatal problem. Verizon and the station owners concluded it was in their mutual best financial interest to build the new tower.
An engineering team was assembled. SkyJack Communications would demolish the tower and erect its replacement. KMVI would provide a new ATU. Lawrence Behr Associates—represented by director of site services Michael Hayden—would design and supervise installation of AM collocation technology. Finally, Verizon Wireless would install its antenna system.
Skyjack expertly demolished the tower without damaging the adjacent KMVI studio building or cluttering nearby roadways. The new steel tower began to rise. Watch the old tower come down below.
Configuring the new structure for AM broadcasts was challenging. The original tower’s 450-foot height translated to 90.6 electrical degrees, which is usual and customary for this class of facility. The new tower would top out at just 180 feet, or 46 electrical degrees. The electrically short tower presented several serious engineering issues for Hayden in the areas of impedance and base voltage.
Hayden recommended using the LBA Technology product CoLoCoil®. This was a logical choice because the design uses tuned resonant circuits instead of “capacitive coupling” as seen in standard “iso-coupler” devices. Tuned resonant circuits present a lower capacitive footprint to the tower’s lump base capacitance. It also allows a DC path for the Verizon signal and control systems as well as any tower-mounted amplifier systems.
Because of the higher than normal tower base voltages, a high-voltage model of the CoLoCoil® was designed, manufactured, tested, and sent off to Hawaii, where Verizon and KMVI now happily co-exist.
Colocation provides many happy endings. They each feature an AM radio station with a new revenue stream, a wireless carrier with a place to hang its antenna, and a happy community devoid of raucous public hearings.
Erection of a new tower on a new plot of land sometimes is the only way to get an antenna in the air. But where mating a wireless antenna to an AM structure is an option, colocation is the best—and happiest—answer.
Contact Mike Britner, VP-Sales at email@example.com to discuss your AM collocation opportunities.
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