HP 81101A Reference Manual page 107

practice, start points may shift with changes in transition time) when
transition times are varied. This is more convenient for programming and
the width display is easy to interpret.
Pulse Delay
Interval between leading edge medians of trigger output pulse and output
pulse:
Trigger
Output
Output
Signal
Fixed Delay
The specified and displayed value is that obtained with the fastest
leading edge. Pulse delay has two components, a fixed delay from trigger
output to output signal and a variable delay with respect to the trigger
output.
Double Pulse Delay
Interval between leading edge medians of the double pulses.
Double Pulse Delay
Interchannel Delay (Skew)
Interval between corresponding leading edge medians of the output
signals.
Variable Delay
Specifications
Pulse Parameter Definitions
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