1S1: Difference between revisions

The 1S1 is a sampling plug-in for 500-series scopes.  It has its own trigger and timebase.  The oscilloscope's timebase is usually set to a relatively slow sweep rate when using a 1S1.  The 1S1 has a 50-Ohm GR connector for signal input.  The plug-in supplies power to active probes such as the P6032 cathode follower probe.  The 1S1 can operate in normal self-swept mode or an external sweep signal can be applied to the 1S1.  With the 1S1's internal sweep disabled, the horizontal-in and vertical-out connections can be used so the the 1S1 acts as a lookup table, a mapping of x to y, a function.   In this mode, the horizontal-in voltage controls to the time after the trigger event when the sample should be taken, and the vertical-out voltage corresponds to the voltage measured at that instant.  This allows a waveform to be digitized using an arbitrarily slow DAC and ADC.  But perhaps more importantly, by setting a constant horizontal-in voltage, it allows the output signal at one equivalent time instant to be processed in the time domain.  For example, this allows the voltage to be low-pass filtered, so that it can be more accurately measured.  The other reason why one might want a signal the consists of multiple sequential measurements of the same equivalent-time instant is that statistics can be calculated on these observations.  For example, one might want to know, when testing a logic gate, what is the propagation delay such that 99.9% of the transitions happen faster than this.  The horizontal-in voltage can also be produced, in "manual" mode, by setting a  knob on the 1S1.