The annual ceremony for lighting the Rockefeller Center Christmas Tree in late November had Wireless First, a Clair Global company, wrangling 86 channels of wireless that spanned a full city block.
The successful Wireless First package included the new CF 1090 Fractal Antenna, designed and manufactured by Wireless First/Clair Global and employing a self-similar antenna topology to deliver high gain across a wide, uniform coverage pattern using a small, camera-friendly housing.
“We had multiple stages all over the plaza, and we had to deliver 100 percent coverage with zero dropouts,” says Wireless First chief engineer Josh Flower. “The hosts were free to travel anywhere within that block, and an RF hit on such a high-profile show would be simply unacceptable.”
The 86 channels were divided among intercom, microphones (for performers and hosts), IFBs, and personal monitors. Live performers played on two stages, one on either side of the ice rink in front of the tree.
“The trick was to zone out the receive antennas so that we had consistent coverage around the plaza without allowing the antennas to interfere with each other,” explains Flower. “We set up three zones – one on 49th Street, one on 50th Street, and one in the Channel Gardens directly across from the tree – also using the same receive antenna system to feed both the intercom and the host microphones. That way, we knew anyone who had to transmit would do so to the same antenna system, ensuring the same range no matter what the device.”
Flower used Shure UA870 UHF active directional antennas for the receive side, taking advantage of its inline booster to compensate for line loss or even use line loss as an advantage to ensure that the antennas didn’t interfere with each other. On the transmit side, Flower flooded the area using the Clair Global CF 1090 Fractal Antennas.
“The CF 1090 is very consistent throughout its coverage pattern,” he says. “I was able to place them in more TV camera transparent locations and still guarantee perfect coverage. Even though we were in the heart of New York City, every aspect of the system ended up being tremendously robust.”
In total, three CF 1090s transmitted to 32 drops of wireless intercom, six IFBs, and sixteen channels of wireless personal monitors.
The show’s receiver and transmitter hardware was a mix of top-of-the-line Sennheiser and Shure products. The show hosts used Sennheiser SKM 5200 handheld wireless microphones.
Flower gave them Sennheiser SK 5212 lavaliers for backup and added a redundant receiver rack across from the tree (incidentally, the CF 1090s acted as the receive antenna for these 12 channels). Neither safeguard proved to be necessary.
The musicians switched between the two stages as needed to facilitate the show’s complicated logistics, and a collection of Shure UHF-R wireless microphones delivered the critical vocal inputs. On stage, Sennheiser 2000 and G2 Series wireless personal monitors were utilized.
