Chapter 1 Performance Tests

Test 2: Trigger Level (HP 53131A/132A Only)

7In the Counter’s Channel 1 Trigger/Sensitivity menu, change the SLOPE to NEG.

8Set the HP 3325B DC OFFSET to +60 mV.

9On the Counter, press Run key.

10Now, decrement the offset on the HP 3325B by 1 mV until the

Counter’s Gate annunciator flashes and continue decrementing until the Counter displays a stable reading of approximately 1 MHz.

Observe the offset value on the display of the HP 3325B. Record the value__________ mV.

11Add the lower peak voltage (40mV) of the 80 mVp-p signal to the offset value in step 10 (for example, 21 mV 40 mV = 19 mv.)

This result is the lower hysteresis level.

Record the lower hysteresis level __________ mV.

12Now, add the upper hysteresis value (recorded in step 6) and lower hysteresis value (recorded in step 11).

This is the trigger level; it should be 0.0 V ±15 mV.

13Record the trigger level value in the appropriate place in the Performance Test Record (Test 2, Line 1).

14Repeat steps 1 through 13 for Channel 2.

15Record the trigger level value in the appropriate place in the Performance Test Record (Test 2, Line 2).

16Disconnect the test setup.

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Assembly-Level Service Guide

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Image 43
HP 181A manual This is the trigger level it should be 0.0 V ±15 mV