Kenwood CS-5140 Instruction Manual

• External S y n cWhen the S O U R C E selection is in E X T , the input signal atthe E X T . T R I G INPUT (§) jack becomes the trigger. Thissignal must have a time or frequency relationship to thesignal being observed to synchronize the display. Externals y n c is prefered for waveform observation in many applica-tions. For example, Fig. 7 s h o w s that the sweep circuit isdriven by the gate signal when the gate signal in the burstsignal is applied to the E X T . T R I G INPUT jack.S h o w s the input/output signals, where the burst signalgenerated from the signal is applied to the instrument undertest. T h u s , accurate triggering can be achieved withoutregard to the input signal fed to the INPUT (5) or (§) jackso that no further triggering is required even when the inputsignal is varied.E X T . TRIGTrigger signal(Gate signal)Fig. 7Waveform with high frequency noiseTrigger signal by HF rejectionFig. 8• Triggering LevelTrigger point on waveform is adjusted by theL E V E L / P U L L S L O P E (fj) control. S h o w s the rela-tionship between the S L O P E and L E V E L of the trig-ger point. Triggering level can be adjusted a snecessary.SLOPE " - " RANGEFig. 9(2) After the S O U R C E has been set, the trigger pointcan be set by rotating L E V E L / S L O P E control @ .(3) Select the coupling switch @ .A C :T h e trigger signal is capacitively coupled, so its DCcomponent is cut, giving a stable trigger which isnot affected by the DC component. With this ad-vantage, this position of the coupling switch is con-veniently s e l e c t e d for ordinary applications.However, if the trigger signal is lower than 1 0 Hz,the trigger signal level becomes attenuated,resulting in difficulty in triggering.HF RE J :T h e trigger signal is supplied through a low-passfilter to eliminate the high-frequency component(higher than 1 0 kHz), giving a stable triggering withlow-frequency component. When high-frequencynoise is superimposed over the trigger signal asshown in Fig. 8 , the high-frequency noise is cut toprovide a stable trigger.• Auto TriggerWhen the T R I G MODE @) selection is in A U T O , thesweep circuit becomes free-running as long as thereis no trigger signal, permitting a check of GND level.W h e n a trigger signal is present, the trigger pointcan be determined by the L E V E L control for obser-vation as in the normal trigger signal. When the trig-ger level exceeds the limit, the trigger circuitbecomes free-running where the waveform startsrunning.NOTE: If, with the T R I G MODE switch set toNORM, no trigger signal is input or the trig-ger signal exceeds the triggering range,sweeping is stopped and trace will not bedisplayed.• HOLD OFFIn case of triggering difficulties that may occur withs i g n a l s containing different pulse durationsalthough the pulse repetition itself is constant a ss h o w n below, or with complicated signals such as aT V signal, turn the HOLD O F F control (g) to ob-tain a stable triggering.15Input signal toamplifier, etc.Output signal fromamplifier, etc.S L O P E " + " RANGELEVEL