1) RF input 1 Connector: N type female Impedance: 50Ω (nominal) VSWR: <1.7 : 1 (Band 0, input attenuator: >10 dB) <2.0 : 1 (Band 1, input attenuator: >10 dB) 2) RF input 2 Connector: K type female Impedance: 50Ω (nominal) VSWR: <1.7 : 1 (typical) (Band 0, input attenuator: >10 dB) <2.0 : 1 (typical) (Band 1, Band 2, Band 3, input attenuator: >10 dB) <2.5 : 1 (typical) (Band 4, input attenuator: >10 dB) 3) Calibration output Connector: BNC female Impedance: 50Ω (nominal) Frequency: 20 MHz Level: -20 dBm 4) Frequency reference input Connector: BNC female Impedance: 50Ω (nominal) Frequency: 1, 1.544, 2.048, 5, 10, 12.8, 13, 13.824, 14.4, 15.36, 15.4, 16.8, 19.2, 19.44, 19.6608, 19.68, 19.8, 20, 26 Level: 0 to +16 dBm