The Amplifier Research 75A250A is a solid-state RF amplifier delivering 75 watts CW minimum across 10 kHz to 250 MHz with instantaneous bandwidth operation. Built on push-pull MOSFET circuitry, it achieves 45 dB typical gain with ±1 dB flatness and operates unconditionally into any load impedance without damage or oscillation. The unit accepts modulated input signals—AM, FM, or pulse—and reproduces them faithfully at the output. Front panel RF gain control and remote operation via IEEE-488 GPIB or RS-232 enable flexible laboratory integration. Over-temperature and input overdrive protection safeguard against faults, while a digital display reports operational status and fault conditions in real time.
Technical Specifications
• Frequency Range: 10 kHz to 250 MHz instantaneous bandwidth
• Output Power: 75 W CW minimum; 100 W CW nominal; 50 W linear at 1 dB compression (46.99 dBm P1dB)
• Gain: 45 dB typical; 49 dB minimum at maximum setting; 18 dB continuous adjustment range
• Gain Flatness: ±1 dB typical and maximum
• Input/Output Impedance: 50 Ω; input VSWR 1.5:1 maximum; output VSWR 2.0:1 maximum
• Input Power for Rated Output: 1.0 mW maximum
• Noise Figure: 6 dB typical (above 1.0 MHz)
• Harmonics: 20 dBc
• IP3: 57 dBm / 501.19 W
• AC Power: Universal autoranging 90–135 VAC or 180–270 VAC; 47–63 Hz; 400 W nominal consumption
• Connectors: N-type female input; N-type output
• Cooling: Air-cooled with built-in fan
• Dimensions: 50.3 × 15.5 × 37.6 cm; 20.5 kg
– Key Features
• Load-mismatch tolerant: 100% rated power operation with any impedance
• Diode limiter input overdrive protection
• Over-temperature shutdown with automatic fault reset
• Remote control via GPIB and RS-232 asynchronous full-duplex serial
• Built-in AC circuit breaker protection
– Typical Applications
• RF susceptibility testing
• Antenna and component characterization
• Watt-meter calibration
• Driver stage for higher-power amplifiers and frequency multipliers
– Compatibility & Integration
IEEE-488 GPIB and RS-232 enable integration into automated test systems. The amplifier reproduces AM, FM, and pulse modulation on input signals without distortion, supporting complex signal conditioning in laboratory environments.
