photo Ampegon TSW 2500D Ampegon shortwave transmitters lead the market for more than 70 years and are the best choice for cost-effective, high-efficiency and flexible operation

Ampegon high power shortwave transmitter TSW product line extends from 50 kW to 500 kW. All models feature interfaces for remote and automated operation and are ready for new-age digital transmission with DRM. Ampegon shortwave transmitters come equipped with fast VSWR protection and an interface for a special analysis tool to monitor environmental incidents like lightning, mains, etc.

Craftwork and Quality
Ampegon shortwave transmitters are hand-crafted in our factory in Switzerland to meet the highest quality and industrial design standards. Satisfied customers around the world testify to the superior design, performance and maintainability of Ampegon shortwave transmitters.

TSW 2500D goes Digital
DRM is bringing a bright new future for AM broadcasting. Cristal clear sound in near FM quality can be made available to listeners around the globe. As one of the most cost-effective, reliable technologies in the world, AM radio broadcasting is still the favoured medium for keeping millions of listeners informed.

Integrated DRM Solutions
True to its tradition of combining innovative technology with reliable and time-tested techniques, Ampegon is offering an enhanced and upgraded shortwave transmitter line for integrated DRM solutions.

The Ampegon 500 kW shortwave transmitter, TSW 2500D, enables broadcasters to choose between classical AM analog and/or DRM digital operation.

photo Ampegon Block Diagram TSW 2500D System Overview
The TSW 2500D is equipped with interfaces for remote and automated operation and is ready for new age digital transmission (DRM).

Features of the TSW 2500D especially adapted for DRM include: Radio Frequency Stages
The TSW 2500D is fitted with a small triode in grounded grid configuration as driver circuit for the final stage tetrode.

The preliminary amplifier is a semi-conductor wideband. The integrated stratus DRM modulator/RF exciter serves as radio frequency source. The stratus unit handles both analog and digital transmission modes and readily accepts a DRM/DI stream.

PSM – Ampegon Solid State Modulator
At the heart of every TSW 2500D is the new Ampegon PSM9 solid-state pulse step modulator. Especially designed to meet the stringent requirements for best quality signal during DRM operation, the PSM9 combines classical shortwave engineering at its best with unrivalled digital AM know-how.

More than twenty years of field experience with PSM technology guarantee that the Ampegon PSM9 modulator is the top-of-the-line, offering The PSM is equipped with 48 power modules, designed as 24 dual modules. Each module comprises a modern IGBT switching device, an integrated step-start system, and integrated safety features like short-circuit protection and IGBT supervision. The PSM9 modules are available in either forced air or water cooled version.

photo Ampegon Water-cooled PSM9 Module Enhanced Transmitter Control System: ECOS2
ECOS2 (enhanced control system) is the new computer based transmitter control system for all Ampegon shortwave transmitters. The system is available with or without DRM functionality.

ECOS2 (enhanced control system) controls and monitors all processes inside the transmitter and provides clearly visible – as well as audible – alarm notifications. The ECOS2 system supports a simple, well-structured user interface on an integrated colour touch screen monitor. It also supports remote access and lets you easily control the transmitter locally or from a remote PC via a standard web-interface. An online connection enables performance of remote diagnostics and system updates.

Additionally, the ECOS2 system easily integrates with our Master Series II broadcast control system for complete system management capabilities from simple monitoring of a single transmitter to the coordination and supervision of an entire network.

Automatic Tuning System
Designed to support the latest developments in control technology, the Ampegon automatic tuning system offers a large number of preset values to enable quick and reliable coarse positioning as well as a redesigned, industry-leading, fine-positioning algorithm for the utmost in tuning control that matches changing VSWR conditions while assuring full power on air.

Water-cooled PSM9 Module
The PSM9 water-cooled module is especially suited for use in areas with problematic atmospheric conditions, like corrosion, salt, pollution or dust.

photo Ampegon Factory in Switzerland

Key Features

  • Fully integrated automatic DRM operation
  • High guaranteed overall efficiency
  • Compact, high-quality design with full accessibility for maintenance
  • Extremely low operational costs
  • Web-interface for remote operation and diagnostics
  • Menu-driven control system with color touch screen
  • Full remote control facilities providing optional remote diagnostics system
  • Fully automatic tuning system
  • BITE – built-in testing equipment
  • Options for different energy-saving operation modes like AMC, DCC and DRM
  • ISO 9001 system design: CE, RoHS compliant
Factory in Switzerland
The transmitters are assembled and tested in the factory before shipment. Dedicated teams make sure that each transmitter fulfils the most stringent standards.


DRM Digital Analog AM
Modulation DRM standard (ETSI ES 201 980) DSB: A3E (option A3E with DCC or AMC)
Frequency Range (MHz) 5.95 - 26.1 MHz (standard)
3.9 - 26.1 MHz (optional)
Frequency Change: 30 sec. max
RF Output Power at Pnom 250 kW mean power with 9 dB crest factor Carrier: 500 kW
Output Impedance 50 Ω unbalanced or
300 Ω balanced (option)
Permissible VSWR 2.0 at 50 Ω unbalanced
1.7 at 300 Ω balanced
Mains Power Supply 3 - 24 kV, 3-phase
400V, 3-phase and neutral
Frequency 50 or 60 Hz (±2 Hz)
Power Factor ≥ 0.95 at nominal AM output power
Overall Efficiency at Pnom (standard cooling included) guaranteed: ≥ 65%
typically: ≥ 70%
guaranteed: ≥ 75%
typically: ≥ 77%
Performance Out of Band: Compliant ETSI EN 302 245-2
MER: ≥ 30 dB
Compliant ETSI EN 302 245-2
(for bandwidth up to 10 kHz)
AF response: ±1.5 dB (50 - 7500 Hz)
AF distortion: ≤ 3.5% (75 - 7500 Hz)
Noise level: ≤ 60 dB rms unweighted
Audio Input DRM/DI Analog: 0 - 20 dB into 600 Ω balanced
Digital: AES3, IEC 60958 and EBU 3250
Local Operation Local control through 15" touch screen
Remote Control & Supervision Ampegon MasterSeries II software,
Web-Interface, SNMP V2c
Environmental Conditions Ambient temperature: +1° - +45°C
Maximum humidity: 95% non-condensing
Dimensions RF Cabinet: (LxWxH):
4800 mm x 1600 mm x 2100 mm
PSM: (LxWxH):
3000 mm x 2500 mm x 2000 mm
Personnel Safety IEC 215, EN 60215
Specifications may change without notice

RF stages AF stages and modulator
Number Type Number Type
1 TH576

1 CTK 12-1


ITU Country
ITU Country