Press Release

Rohde & Schwarz’s fully liquid-cooled radio transmitter calls out competitor solutions which are, at best, a hybrid liquid/air-cooled solution.
Rohde & Schwarz’s fully liquid-cooled radio transmitter calls out competitor solutions which are, at best, a hybrid liquid/air-cooled solution.
Mar 09, 2020 | Broadcast and Media

Rohde & Schwarz enhances and extends world’s first completely liquid-cooled transmitter for FM and HD Radio(TM) applications

Rohde & Schwarz’s fully liquid-cooled radio transmitter – R&S THR9 – calls out competitor solutions which are, at best, a hybrid liquid/air-cooled solution.

On its NAB 2020 booth (SL5016), Rohde & Schwarz will showcase a number of strategic enhancements to the R&S THR9 - the world’s first totally liquid-cooled transmitter for FM and HD Radio applications. With the latest version of the R&S THR9 transmitter not only are the transistors liquid-cooled but also the entire power amplifier stage, including power supplies, coupling units and absorbers. Consequently, the power amplifier stage of the has no moving parts which may break, nor can it introduce humidity and dust to the amplifier units.

Rohde & Schwarz’s fully redundant liquid-cooling technology generates lower electrical costs for cooling and ventilation, features a smaller footprint and offers increased reliability. The R&S THR9 transmitter is designed for permanent reliable operation at 45°C/113°F at full output power. At 40kW output power only 1kW of heat is dissipated into the environment, so air conditioning requirements are minimal. The unit’s footprint is comparable with competitive systems that offer 20 kW less output.

Importantly, the R&S THR9 runs on architecture that is independent of Microsoft Windows for all HD Radio entities including its Importer, Exporter and Exgine. As a consequence, users of this fully professional solution are not dependent on the availability of security patches for MS Windows for reliable efficient operation.

Compared with competitive manufacturers, Rohde & Schwarz’s HD Radio transmitter is significantly more robust and provides a richer feature set. For HD Radio applications, the R&S THR9 features a new HD Sync functionality, which provides automatic alignment of the HD Radio Diversity Delay between the analog and digital signals of a radio station. Developed by Rohde & Schwarz, HD Sync eliminates unwanted blending artifacts that can degrade the listening experience and prevent recurring and extensive time alignment procedures for station engineers.

HD Sync for Exporter ensures full compliance to the HD Radio time alignment specifications, which means the analog and digital signal time alignment is always in the permitted range of -3 to +3 samples and is fully automatic. This minimizes stress for engineers, reduces costs for station owners and enhances listener experience, especially when receiving radio in an area of weak digital but still strong analog coverage.

For optimum operation, the R&S THR9 works in unison with the R&S RelayCaster solution, which enables the use of public internet connections for the STL (Studio Transmitter Link) of HD Radio transmitters. As a result, dedicated and expensive IP links for the feeding I2E or E2X streams are not necessary, helping radio stations to reduce infrastructure costs while not compromising reliability nor transmission quality.

“The R&S THR9 is an awesome piece of technology and is uniquely positioned in the global radio transmitter market,“ commented Manfred Reitmeier, Vice President Transmitter and Amplifier Systems at Rohde & Schwarz. “The pure liquid-cooled design liberates radio broadcasters: by transporting 90% of the generated heat out of the building through the cooling liquid, the complexity of a reliable station cooling system is massively reduced. Now for the first time, the air time of the radio transmitters does not depend on the efficiency and reliability of the station’s HEVC system.”

Rohde & Schwarz

The Rohde & Schwarz technology group is among the trailblazers when it comes to paving the way for a safer and connected world with its leading solutions in test & measurement, technology systems, and networks & cybersecurity. Founded more than 85 years ago, the group is a reliable partner for industry and government customers around the globe. On June 30, 2020, Rohde & Schwarz had around 12,300 employees worldwide. The independent group achieved a net revenue of EUR 2.58 billion in the 2019/2020 fiscal year (July to June). The company is headquartered in Munich, Germany.
R&S® is a registered trademark of Rohde & Schwarz GmbH & Co. KG.
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Rohde & Schwarz Broadcast & Media

Rohde & Schwarz is a leading technology innovator in broadcast and media for over eight decades. With technology for live studio production, premium post production, playout delivery and distribution Rohde & Schwarz helps creative, operational and technical people make and deliver great programs for great entertainment. Rohde & Schwarz develops virtualizable, software and hardware solutions for live ingest, transcoding, graphics & branding, master control playout, automation, multiviewing, monitoring, intelligent storage as well as solid state satellite amplifiers and terrestrial transmission for radio, linear television, OTT and VOD. As media people we design for media people and with our engineering prowess and dedication to customer support we know exactly how to make it happen to highest quality. Privately owned and engineering led.

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