The 8621A RF Drawer houses the 86300 series RF Modules. The standard drawer will accept one fundamental oscillator module. However, with the 1.8 to 4.2GHz fundamental oscillator module, the standard drawer also accepts the 0.1 to 2GHz heterodyne module to give 0.1 to 4.2GHz coverage.
Option 004 = Rear RF Output - Option 010 = -70 dB Attenuator - Option 100 = Multiband Capability