The yellow LED indicates the system on. In this case amplifiers are stayed in standby mode and no output at all. No any action occurs on the beam.
Set up the sinusoidal waveform output. Set frequency to 10.25 kHz. Adjust amplitude Vpp to 250 mV level. Then adjust phase shifter until a circle pattern appears. The two read back signals comes from current sensor Pearson probe, that has a 0.1 ratio of voltage and current. It means one ampere current through the probe will produce 0.1 V voltage.
The Moeller transportation optics produces an elliptical beam spot on Moeller target. The ratio of horizontal to vertical is about 4. To get better effect by using Moeller raster, one may reduce x-amplitude and increase y-amplitude or reversely. MR amplitude controller is located in the same raster rack. You may use x and y two knobs for adjustment.
The dual x-y display of the Tektronix digital scope can be used to display instant MR current pattern. The scope is shared by target raster system. The first position of the switch is to display Moeller raster pattern.