Amplifier Research 50S1G4A

The Amplifier Research 50S1G4A is a solid-state, air-cooled broadband RF amplifier delivering 50 watts minimum CW output across 0.8 GHz to 4.2 GHz. Built for driver applications in wireless, communications, and EMC testing, it combines high gain with linear performance and instantaneous bandwidth to faithfully reproduce AM, FM, and pulse modulation without distortion. The unit features automatic RF input leveling protection, mismatch tolerance across any load impedance, and over-temperature safeguards.

Front-panel gain control provides approximately 10 dB adjustment range, while IEEE-488 and RS-232 interfaces enable remote operation. A digital display monitors operational status and fault conditions. The amplifier mounts to a benchtop cabinet or fits standard equipment racks.

Technical Specifications

• Output Power: 50 W minimum CW; 70 W nominal at 1 dB compression; 60 W at 1 dB compression point


• Frequency Range: 0.8 GHz to 4.2 GHz


• Gain: 47 dB maximum; 10 dB adjustment range


• Small Signal Flatness: ±1.5 dB typical, ±2.0 dB maximum


• Input for Rated Output: 0 dBm maximum (1.0 milliwatt)


• Output Impedance: 50 ohms


• Modulation: AM, FM, pulse (linear reproduction)


• Spurious Signals: Low level


• Power Requirements: 100/240 VAC, 850 VA, single phase


• Dimensions: 50.3 × 24.9 × 54.6 cm


• Weight: 32 kg (100 lbs)

Key Features

• RF input leveling circuit - automatically controls input to first stage when input exceeds 0 dBm


• Full mismatch tolerance - operates without damage or oscillation at 100% rated power under any load impedance condition


• Over-temperature protection - removes DC voltage to amplifier stages on cooling failure or blockage


• Type N female RF connectors (rear panel)


• Low spurious signal output

Typical Applications

• Driver amplifier for wireless and communications component testing


• EMC testing with undistorted modulation envelopes


• Multi-frequency laboratory measurements

Compatibility & Integration

• Local Control: Front panel gain potentiometer


• Remote Control: IEEE-488 (GPIB), RS-232


• Status Monitoring: Digital display for operate status and fault indication