Operating instructions

University of Saskatchewan
Electrical Engineering Laboratory Equipment Manual
Holdoff keeps a trigger from occurring until the amount of time set has passed since the
last trigger. Used, on a repeating pattern of a waveform, to trigger on the same edge of the
pattern.
Edge triggers on a falling or rising transition. Pulse Width triggers after a time set pulse
width has occurred. Pattern trigger is a logical AND of the channels. Channels can be specified
high, low, or don’t care (X). A rising or falling edge can be set for only one channel. A trigger
will occur when the specified conditions for all the channels is true.
Acquire Waveform
In Peak Detection mode signals longer then 5 nS will be displayed at any time/div speed.
This mode can be used at time/div speeds slower then 1 mS/div. It has no effect at higher speeds
as the scope will display 5 nS peaks in normal acquisition mode. Digital channels always have
peak detection on.
In Realtime mode the waveform produced is from samples during one trigger event. A
reconstructive filter is used to fill in, the waveform displayed, when less than 1000 samples are
available in the time span of the display. At sweep speeds of 200 nS/div and faster, less then
1000 samples are available on each trigger. Realtime mode is only necessary at these sweep
speeds. Realtime is used to capture infrequent events or a changing waveform. The waveform
displayed, with Realtime off, is constructed from multiple triggers.
Averaging reduces noise. The scope responds slowly, to changes, with averaging on.
Turn averaging off when adjusting the scope or changing signals. High Resolution mode (
averages = 1) is used when the sampling rate is faster then the rate at which the samples are
being stored. Samples are averaged together for each display point with this mode. The slower
the time/div speed the greater the samples averaged. Bit resolution will be increased at slower
sweep speeds with High Resolution.
Single acquisition stores at least twice the number of samples then the Run mode. Higher
sampling rates occur at slower sweep speeds due to a larger memory available in Single mode.
Horizontal
Measurements and functions are performed on display data. The resolution of
measurements and functions are affected by the resolution of the display. Time/div and volts/div