Tektronix CSA8000B - Manual (Page 319)

Measurement Reference Parameters and Methods
CSA8000B & TDS8000B User Manual B- 57
Pulse Sources
The automatic measurement system uses the following levels when measuring
Pulse source waveforms. For the Pulse measurements, and their definitions that
use the levels described here, see page B--2.
TcrossH
High
High reference
Low
Low reference
TcrossL
Figure B- 2: Pulse-reference levels
Pulse Measurement
Reference Levels