The S3531B from Saluki Technology is a RF Spectrum Analyzer with Frequency 9 kHz to 3 GHz, Frequency Resolution 1 Hz, Resolution Bandwidth 1 Hz to 3 MHz, Video Bandwidth 10 Hz to 3 MHz, DANL <-155 to -135 dBm. Tags: USB / Computer Controlled, Analyzer with Screen. More details for S3531B can be seen below.