An Iconic Broadcast Tower Gets A Dielectric FM Antenna


SAN FRANCISCO — The Golden Gate Bridge. Coit Tower. The Transamerica Pyramid. Sutro Tower.

These are some of the architectural icons of the City by the Bay, and the latter is the structure that houses many of the San Francisco market’s radio and TV station antennas.

Now, Sutro Tower has installed a Dielectric DCR-S Series FM radio antenna on its 977-foot high steel structure.

It joins nearly 300 resident antennas on the tower, used by 12 TV stations, four FM stations and 35 wireless radio communication users to distribute their signals across the hilly, nine-county Bay Area region. First responders, government agencies, and transportation companies are also among the tower’s wireless radio users.

“We chose the Dielectric DCR-S FM antenna because of its broadband capabilities and excellent axial ratio characteristics,” says Eric Dausman, COO of Sutro Tower Inc. “Because of our central location, the DCR-S antenna’s broadband and multi-channel capabilities, covering 88 to 98 MHz, enables us to multiplex signals and maximize our tower’s capacity.”

Sutro Tower is owned by a consortium of four broadcasters, a relationship that dates to the structure’s construction in 1973.

The antenna was ordered with one particular radio customer in mind—”a major FM radio station serving the Bay Area” Dielectric could not disclose due to contractual reasons.

According to Dausman, many of the initial antennas on Sutro Tower were manufactured by the RCA TV Antenna Division—which Dielectric acquired in 1986—and operated reliably until 2009 when new Dielectric antennas were installed for VHF and UHF television broadcasting.

“Since Sutro Tower is surrounded by private homes, the structural integrity of our tower, and the mechanical design and construction of the equipment it supports, are extremely important to public safety,” Dausman said. “The tower, antenna and auxiliary systems need to be of high structural quality. We chose this Dielectric antenna because we know their designs meet our structural and electrical requirements, which are that the products must be robust, with a decades-long life cycle.”

Dausman says he received proposals from three other antenna makers as part of the bidding process. “We ultimately chose Dielectric because they had the best track record and technical expertise to custom-design and deliver exactly what Sutro Tower and its resident broadcasters required,” he says.