Available

SD2931-11 RF Power MOSFET 150W 50V HF/VHF/UHF N-Channel Transistor

RF Transistors and Finals • SKU RFB-SD2931-11-DP-001

$120.00

This is a STMicroelectronics SD2931-11 RF power MOSFET, removed as a used donor pull from a working RF unit and bench-checked with a semiconductor analyzer.

The SD2931-11 is a serious 50V RF MOSFET used in HF, VHF, UHF, ISM, and RF power amplifier service. It is designed for large-signal RF applications up to 230 MHz and is rated for 150W minimum RF output with 14 dB gain at 175 MHz. This makes it useful repair stock for technicians working on RF power stages, amplifier modules, ham radio equipment, and hard-to-source PA sections.

This part tested as an N-channel enhancement MOSFET with normal-looking gate behavior, body diode behavior, and low-current analyzer readings. It has not been full RF-output tested after removal.
Vintage Semiconductor History – STMicroelectronics SD2931 RF Power MOSFET

The SD2931 RF power MOSFET family was developed by STMicroelectronics, one of the world's leading semiconductor manufacturers. STMicroelectronics was formed in 1987 through the merger of Italy's SGS Microelettronica and France's Thomson Semiconducteurs, combining decades of European semiconductor expertise into a global technology company.

Introduced as part of STMicroelectronics' high-power RF transistor product line, the SD2931 family became widely used in commercial communications equipment, broadcast transmitters, industrial RF systems, amateur radio amplifiers, and other demanding RF power applications. The device earned a strong reputation for ruggedness, reliability, and excellent RF performance.

Over the years, several versions of the SD2931 were produced, including devices optimized for different power levels and operating requirements. The transistor family became particularly popular among amateur radio amplifier manufacturers and was frequently selected for high-performance RF amplifier designs because of its ability to deliver substantial RF output power while maintaining dependable operation.

Although many original SD2931 variants are now considered legacy or obsolete devices, they remain highly sought after by repair technicians, amplifier builders, radio restorers, and collectors maintaining older communications equipment. Original STMicroelectronics devices are especially valued when repairing equipment designed around the SD2931 platform.

Many amateur radio operators recognize the SD2931 family as one of the classic RF power MOSFET series that helped bridge the transition from earlier bipolar RF power transistor designs to modern high-performance RF MOSFET technology.

RF Boneyard™ Note: The SD2931 represents an important milestone in RF power semiconductor development and remains one of the most recognized RF power MOSFET families among amplifier builders, service technicians, and radio enthusiasts worldwide.