310

The Sonoma Instrument 310 is a broadband, low-noise preamplifier covering 9 kHz to 1 GHz (-3 dB), designed for EMI measurements, antenna signal amplification, and general-purpose low-level RF signal amplification applications requiring high gain flatness and low noise across a wide frequency range. With a gain of 32 ±1.5 dB at 100 MHz, gain flatness of ±0.5 dB from 25 kHz to 800 MHz, and a typical noise figure of 1.8 dB from 5 to 500 MHz, it delivers exceptional amplitude accuracy and sensitivity across the bulk of its operating range.

Key specifications include an output at 1 dB gain compression of +10 dBm, a third order intercept point of +23 dBm at 300 MHz, harmonic distortion of -39 dB at 0 dBm output and 200 MHz, 35 dB of reverse isolation, input return loss of 8 dB, and output return loss of 10 dB — both measured from 20 kHz to 1 GHz. The equivalent input noise voltage is 0.55 nV/√Hz from 5 to 500 MHz and 0.59 nV/√Hz at 1 GHz, including noise contribution from a 50 Ω source. The maximum input for linear operation is approximately ±25 mV (-22 dBm), with an input damage level of ±2 V DC. The unit is AC coupled with 50 Ω impedance and uses Type N female connectors at both input and output.

Time domain performance includes a transition time of 350 psec and group delay variation of ±75 psec from 45 MHz to 1 GHz — making it well-suited for wideband pulse and transient measurements in addition to CW EMI applications. The unit is mains-powered at 100, 120, 220, or 240V AC / 50–60 Hz at 20 VA. Physical dimensions are 91 × 109 × 183 mm (H × W × D) with a net weight of 1.5 kg.