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MegaZoom Concepts and Oscilloscope Op eration
To change the logic threshold for digital channels
To change the logic threshold for digital channels
1Press the D15 Thru D8 key or D7 Thru D0 key.
2Press 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 D15Thru D8 or
D7Thru D0 group. Each of the two channel groups can be set to a different
threshold, if desired.
Values greater than the set thresh old are high (H ) and values le ss than the set
threshold are low (L).
3 When the Threshold sof tk ey is se t t o 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