The SUM001 Summer card hosts seven inputs and selects up to four to be summed in the composite output. ON/OFF and signal level control is provided for each of the four selected signals. The signal level of each selected input can be varied from +3 dBm to -30 dBm (75 Ohm load), in 0.1 dBm increments. The composite output is attenuated from 0 to 7.5 dB, in 0.5 dB increments. A fixed-level composite output test signal is also provided. A spare buffer amplifier stage is also provided.

Signal selection, level control, On/ Off and composite output attenuation are all software selectable via the VME bus.

The card is a single-slot 6U x 160 mm VME module, with an included front panel containing SMA interface connectors (J1-J12).