The author is vice president of engineering for Spanish Broadcasting System.
MIAMI — As one of the largest Hispanic-controlled station groups in the U.S., the Spanish Broadcasting System Inc. operates 18 Spanish-language radio stations in top U.S. Hispanic markets including Miami, Chicago, New York, Los Angeles, San Francisco and Puerto Rico, along with the AIRE Radio Network, several TV stations and two internet portals.
In the Miami area, we operate three FM stations — WCMQ(FM)/Zeta 92.3, airing salsa, WRMA(FM)/Ritmo 95.7, airing Cubatón/Reggaeton and WXDJ(FM)/El Zol 106.7, airing Bachata and tropical music — making it a particularly hot radio market for us.
Last fall, we moved our transmitter facilities to the top of the Panorama Tower, a new 85-story skyscraper in Miami’s trendy Brickell district. Compared to our previous Miami high-rise site, this exceptionally high perch — the tallest south of New York — is especially advantageous for over-the-air coverage.
By December 2019, we completed the construction of our new transmitter building atop the Panorama Tower, which now houses three new GatesAir Flexiva FAX-20 kW solid-state transmitters, one for each of our Miami stations. Two of these units serve as main FM radio transmitters for WCMQ and WRMA, while the third serves as a backup for WXDJ. We procured the transmitters and additional gear through SCMS, which provided outstanding customer support and service through the entire process. SMCS also brought in the experts from Klein White Engineering of Phoenix for installation services.
After evaluating the top FM radio transmitters on the market, we chose the 20 kW GatesAir Flexiva FAX20 solid-state air-cooled transmitters, primarily because their inherent PowerSmart Plus architecture enables greater energy efficiency. Over time, we expect that this energy efficient design will result in substantial energy savings that will contribute to a solid return on investment.
Since the rooftop transmitter building is only 26 by 15 feet, choosing transmitters that would pack all the features and functionality we needed into a compact size and footprint was paramount. In fact, we chose the air-cooled Flexiva FAX model because liquid cooling was not practical given that the site does not have sufficient space to accommodate the necessary plumbing.
With the Flexiva’s low-maintenance design, we also find it easy to perform routine maintenance on the transmitters just by opening the front panel of their cabinets. Inside the transmitter, we can replace key components, such as power supplies and amplifiers, without having to interrupt the air signal because these modules are hot-swappable.
Exciters
Our GatesAir package includes Flexiva software-defined exciters, which promote the reliability and stability that 24/7 operations require. With their inherent SNMP connectivity, this Flexiva transmitter model can be closely monitored from a remote location by our technicians. In fact, the system triggers alarms and notifications whenever immediate attention is required.
While WXDJ is already airing in HD Radio on its main transmitter, located at another site, we plan to enable HD Radio on its back-up transmitter in the near future. The other two stations, WCMQ and WRMA, will soon offer HD Radio for the first time. To facilitate this, our new GatesAir equipment package includes the Flexiva FMXi 4g HD Radio platform, which comprises companion HD Radio Importer and HD Radio Exporter software.
Our HD Radio programming originates from our broadcast studios in Miami’s Medley district, and the signals are transported to the transmitter site nine miles away via GatesAir Intraplex IP Link 200 codecs. These IP STL codecs use our two high-performance WAN services — AT&T and Atlantic Broadband — simultaneously, which permits signal failover to a redundant path whenever necessary. That is made possible by GatesAir’s Intraplex Dynamic Stream Splicing software built into the codecs.
Once transported to the Panorama site, the program signals first pass through an Orban audio processor, which feeds them to the GatesAir HD Radio Importer/Exporter software that is downstream. At the transmitter site, our stations share a Shively broadband panel antenna. With its two-input antenna panel design, this Shively antenna can broadcast RF signals according to two different profiles, such as omnidirectional and unidirectional, simultaneously.
Combination
In order for our three separate stations to share the same antenna, their respective Flexiva transmitter outputs must be delivered to the antenna via a complex workflow that performs high-level combining and bandpass filtering. WCMQ and WXDJ combine into a single RF signal that is broadcast in an omnidirectional pattern radiating from the Miami metro and Boca Raton south to Key Largo. WRMA’s signal, which combines with the other two after passing through a bandpass filter, is broadcast from the antenna’s hybrid side in a single direction, north towards Broward County.
With the Flexiva’s compact, energy-efficient design, GatesAir enabled us to transition from our older, tube-based transmitters to this next-generation solid-state technology. And coupled with the other GatesAir RF products we’ve installed, this solution saves valuable space, streamlines routine maintenance, supports our HD Radio roadmap, and boosts overall signal quality and reliability.
