CS-1044Fig. 3(D AC-GND-DCThree-position lever switch which operates as follows:A C : Blocks dc component of channel 2 inputsignal.GND: Opens signal path and grounds input to ver-tical amplifier. This provides a zero-signalbase line, the position of which can be usedas a reference w h e n performing dcmeasurements.DC: Direct input of ac and dc component of chan-nel 2 input signal.(9) y INPUT JackVertical input for channel 2 trace in normal sweepoperation. External horizontal input in X-Y operation.(f(D • POSITION/PULL INVT POSITION:Rotation adjusts vertical position of chan-nel 2 trace.INV: Push-pull switch selects channel 2 signalinverted (PULL INV) when pulled out.(Hereafter PULL INV is described as CH2INV.)10(Q) MODESelects the basic operating modes of the oscilloscope.C H 1 : Only the input signal to channel 1 isdisplayed as a single trace.CH2: Only the input signal to channel 2 isdisplayed as a single trace.ALT: Alternate sweep is selected regardless ofsweep time.CHOP: Chop sweep is selected regardless ofsweep time at approximately 2 5 0 kHz.ADD: The waveforms from channel 1 and chan-( C H 1 + C H 2 ) nel 2 inputs are added and the sum isdisplayed as a single trace. When the CH2INV (fj|) button is engaged, the waveformfrom channel 2 is subtracted from thechannel 1 waveform and the difference isdisplayed as a single trace.® POWER, SCALE ILLUMFully counterclockwise rotation of this control (OFFposition) turns off oscilloscope. Clockwise rotationturns on oscilloscope. Further clockwise rotation ofthe control increases the illumination level of the scale.(fj) PILOT LampLamp lights when oscilloscope is turned on.CS-1025