Agilent Technologies 24A Manuale Utente
4-37
MegaZoom Concepts and Oscilloscope Operation
To change the logic threshold for digital channels
To change the logic threshold for digital channels
1 Press the
D15 Thru D8
key or
D7 Thru D0
key.
2 Press the
Threshold
softkey, then select a logic family preset or select
User
to define your own threshold.
The threshold you set applies to all channels within the selected
D15 Thru D8 or
D7 Thru D0 group. Each of the two channel groups can be set to a different
threshold, if desired.
threshold, if desired.
Values greater than the set threshold are high (H) and values less than the set
threshold are low (L).
threshold are low (L).
3 When the
Threshold
softkey is set to
User
, press the
User
softkey, then turn
the Entry knob to set the logic threshold voltage for the channel group.
Logic family
Threshold Voltage
TTL
1.4 V
CMOS
2.5 V
ECL
–1.3 V
User
Variable from –8 V to +8 V