A low-noise rf amplifier based on a dc SQUID (SQA) is developed and tested within frequency range 3.0-4.5 GHz. The 4-channel chips are designed using proven balanced output configuration; they employ special damping filters. Each channel is tested separately demonstrating the following parameters at 3.95 GHz central frequency: gain (9.5 +/- 1.0) dB, 3-dB bandwidth 300 MHz and noise temperature (1.0 +/- 0.5) K. The 1-dB gain compression estimate is 50 K * GHz for bias voltage 80 mu V and characteristic voltage 285 mu V.