Getting Started with the Tektronix 4000 Series
Notice that the oscilloscope loses its stable
trigger and the waveform now appears to
randomly scroll b y.
2. Push the Force Trig button once and
notice that the oscilloscope shows a single
acquisition for a moment. This gives you
an idea of what the waveform looks like
so you can set an appropriate and stable
trigger.
Tektronix 4000 Oscilloscope Demo In struction Manual 9