Amplifier Research 175S1G4

The Amplifier Research 175S1G4 is a solid-state broadband microwave amplifier delivering 175 watts minimum RF power across 0.8 GHz to 4.2 GHz instantaneously. Purpose-built for driver amplifier roles in wireless component testing and EMC applications, it combines high gain with low distortion through push-pull circuitry architecture.

Technical Specifications

• Rated Power Output: 175 W minimum; 190 W at 3 dB compression; 165 W at 1 dB compression


• Frequency Range: 0.8 GHz to 4.2 GHz (instantaneous bandwidth)


• Gain: 52.5 dB minimum; continuous adjustment across 15 dB minimum range in 4096 remote steps


• Input Power: 1.0 mW maximum for rated output


• Input Impedance: 50 Ω, VSWR 2.0:1 maximum


• Output Impedance: 50 Ω nominal


• Third Order Intercept Point (IP3): 61 dBm typical


• Harmonic Distortion: −20 dBc maximum at 160 W


• Spurious Signals: −73 dBc typical


• Phase Linearity: ±1.0 deg/100 MHz typical


• Primary Power: 90–132 VAC or 180–264 VAC auto-selected; 50/60 Hz single phase; 1050 W maximum consumption

Key Features

• Mismatch tolerant: operates without damage or oscillation at 100% rated power under any load impedance magnitude and phase


• Automatic Level Control (ALC) with front panel threshold adjustment and RF output protection


• Faithful reproduction of AM, FM, and pulse modulation envelopes


• Air-cooled, self-contained design in portable form factor


• Digital Control Panel with local and remote operation via IEEE-488 interface


• Real-time forward and reflected power display with status reporting

Typical Applications

• Driver amplifier stage for wireless and communication component testing


• EMC and radiated immunity testing requiring undistorted modulation fidelity


• Broadband RF source for subsystem characterization across L-, S-, and C-band frequencies

Compatibility & Integration IEEE-488 remote interface supports integration into automated test systems. Menu-driven softkey control with rotary encoder adjustment enables rapid gain reconfiguration across the 15 dB adjustment range.