19Swìtchìng Trigger SourceWhen thei'4*'i@"'MODE control is set at CHI, ALT, CHOP, or ADDand theSOURCEcontroi is set at VERT MODE,the signal source for the trigger becomeschannei l. At this time, if the CHI signal is too complicated, making the triggerpoint too difficult, switch the SOURCE control to the CH2 setting. The CH2signal will be simple enough for a stable trigger point setting. However, whenthe waveforms of both channeis are too complicated, use an externai source toset the trigger point.If signals having different frequencies are input to CHI and CH2, set the"4$'$;@h."MODE selector to ALT and SOURCEselector to VERT MODE. Inputsignals to CHI and CH2 are used as the trigger signal sources, which alternate inevery sweeping. Thus, both signals are triggered.Swìtchìng Vertical Operation ModesWhen the tfijii@1MODE control is set at CH2, the CRT screen will displaythe signal applied to the channel2 INPUT terminai. The amplitude can be alteredusing the channel 2 VOLTS/DIVcontrol. The procedures for switching the sweeptime and setting the trigger point are the same as for channell.When the "4*"(1.;" MODEcontrol is set at ALT, the CHI and CH2 signais aredisplayed one after the other for each sweep.When the 'f*,,@ti,1 MODE controi is set at CHOP, the CHI and CH2 signalsare sub-divided according to time and displayed on the screen.When the ",*II@,. MODEcontroi is set at ADD, CHI and CH2 signais will becombined (CHI+CH2) on the CRT display screen. If the CH2 INV controi ispressed in this condition the differential (CHI-CH2) of the two channeis will bedisplayed. In order to measure displayed waveforms at the ADD setting, it isnecessary that the VOLTS/DIV controi settings be the same for both channels.DUAL TRACE OPERATIONSFigure 7. Relationship between TRIGGERINGMODEand SLOPETV-UNETV-FRAMESLOPE+Composite Video Sìgnal DisplayWhen inputting composite video signals, set the ITRIGGERINGI MODE to eitherTV -FRAME or TV-UNE. Also switch the SLOPE control in accordance withsignal polarity.