It passes all self tests and self calibration. It appears to have excellent output across the frequency spectrum from 10Mhz to 20 Ghz at high power levels and low power levels. It has a 2 year NIST calibration performed may 2016.

• +17 dBm calibrated output power
• -50 dBc harmonics <20 GHz typical
• SSB phase noise <-80 dBc at 10 GHz and 10 kHz offset
• Complete analog sweeper
• 1 Hz frequency resolution (Option 008)
• Pulse, amplitude and frequency modulation (8360B Series only)
• -110 dBm output power with step attenuator (Option 001)
   

The Keysight 83623B high power synthesized sweeper is the standard of excellence for applications requiring the high performance and accuracy of a synthesized source and the speed and versatility of a sweep oscillator. Synthesized broadband frequency coverage and precise 1 Hz frequency resolution (Opt 008) are generated by indirect synthesis, enabling the Keysight 83623B to achieve low single-sideband phase noise performance. It also delivers excellent harmonic performance with harmonics at least 25 dB below the carrier from 2.0 to 20 GHz.