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.

2Press the Threshold softkey, then select a logic family preset or select User to define your own threshold.

Logic family

Threshold Voltage

TTL

1.4 V

CMOS

2.5 V

ECL

–1.3 V

User

Variable from –8 V to +8 V

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.

Values greater than the set threshold are high (H) and values less than the set threshold are low (L).

3When 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.

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Agilent Technologies 24A, 54621D, 42A, 54621A, 22A, 41A manual To change the logic threshold for digital channels