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Section 4.5: Beam/Source ON/OFF
The power supply has two output ON/OFF buttons labeled SOURCE and BEAM. When the
SOURCE button is toggled to ON, power is applied to the cathode and neutralizer filaments. The
discharge supply is also turned on. As the cathode filament is heated up to emit electrons, the
discharge supply will ramp to about 150 V. As electrons from the cathode make their way to the
anode, a discharge is started and will be observed by a drop in discharge voltage to its operating
value (typically 55 V). After a discharge has been established, the source has started. The BEAM
button can then be toggled to ON.
When the BEAM button is toggled to ON, power is applied to the beam and accelerator supplies.
The beam and accelerator voltage will ramp in a steady fashion to their desired settings. The beam
can be turned off by pressing either the BEAM or SOURCE button. Turning the beam off by
pressing the BEAM button will leave the source ON. Turning the beam off by pressing the
SOURCE button will extinguish the beam and source.