Fluke 867B - Page 49

Making Measurements
Testing for Logic Activity
2
2-21
Using the Logic Test Softkeys
TTL
3 V
CMOS
5 V
CMOS
/
1
,
2
, and
3
select the trigger point for the
logic activity indicator and frequency reading. “5V
CMOS” is the standard configuration. A new
selection cancels the old selection. See Chapter 8
for threshold values.
4
(
/
) activates the beeper; a beep then sounds
to indicate logic activity. The beeper is off in the
standard configuration. If the reading goes above 30
volts, the safety indicator (
l
) lights.