A Broadband Antenna, RF System Finally Arrive In Puerto Rico

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For a generation of Puerto Ricans, “Alfa Rock 106” was the home for rock and roll music not found anywhere else on the FM dial. Times change, and just after midnight on March 3, 2018, WCAD-FM concluded its broadcast era.


Just before Christmas 2018, the station was reborn, later taking new call letters that better reflect its current programming.

Now, it’s installed a listener-funded Dielectric DCR-M.

It was installed by Dielectric’s CALA region for the No. 2 licensee of radio stations in the U.S.: Educational Media Foundation (EMF).

The Dielectric DCR-M is being used for what is now WJKL-FM 105.7, licensed to San Juan, Puerto Rico. Its Class B 50kw signal comes from a broadcast tower in a rural area of Aguas Buenas, south of San Juan. It’s on a peak in a mountainous, rural area not easily accessible.

EMF worked closely with Dielectric — and, RBR+TVBR has learned, Univision — on a broadband antenna design. It will support both WJKL on 105.7 MHz and a second station in the future.

This station is WKAQ-FM 104.7, the longtime Latin Top 40 station serving Puerto Rico and much of St. Thomas and St. Croix, USVI, as “KQ105.”

Don’t fret: Univision is not involved in any transaction with EMF as it pertains to KQ105.

Rather, the WKAQ-FM tower, adjacent to that used by WJKL, is being decommissioned after years of use and abuse from hurricanes and other weather-related battering. As such, WKAQ-FM and WJKL will be on the same tower.

The center-fed DCR-M from Dielectric accommodates both frequencies (with 1 MHz separation) through a special reduced bay-spacing design that eliminates the need for future field tuning.

Furthermore, EMF added a new, specially designed two-station branch combiner to serve both transmission frequencies, and prevent intermodulation issues from signal mixing inside the transmitters.

Side-mounted to a mountaintop tower with a center of radiation at 118 feet above ground level (1,787 feet above sea level), the DCR-M was specified to withstand the stormy weather elements of Puerto Rico, amplified during hurricane season.

In fact, the project delayed due to several harsh storms including Hurricane Maria in 2017, which caused widespread devastation to the island. The project was revived once power was returned to the remote site and general infrastructure was restored. Then came COVID-19, putting a further wrinkle on the plans for KLOVE Puerto Rico.

Director of Site Development Kim Allison said the antenna design meets the weight and wind-load specifications of the tower. “This was of high importance considering the remote tower location,” she said.

Dielectric worked closely with Sabre to develop a custom mounting system that could support the unique bay-spacing design. This included a standoff pole for the tapered tower architecture, and a bracket design that eliminated complex anti-rotation elements for the antenna bays.

Dielectric also added its “funky elbow” design to reduce ground radiation from the DCR-M, through a inter-bay feed system that optimizes signal coverage without directing radiation downward from the tower.

Dielectric VP/GM Keith Pelletier notes that everything was shipped in a single container to reduce costs, with Sabre designing the stand-off pole in short, modular sections to fit cleanly alongside Dielectric’s antenna.

“This project was a labor of love for Dielectric considering the unforeseen delays and challenges that EMF faced on the road to installation,” Pelletier said. “We are grateful for the opportunity to support EMF and its mission to bring Christian radio programming to the audiences throughout Puerto Rico.”


Additional reporting by Brian Galante.