The QB-904 from Spectrum Control is a RF Amplifier with Frequency 2 to 6 GHz, Gain 33 to 40 dB, Gain Flatness ±2 dB, Noise Figure 6.5 to 8 dB, Output Power 36.02 to 36.9 dBm. Tags: Power Amplifier, Driver Amplifier. More details for QB-904 can be seen below.