HP 181A 1 MHz, stable, Counter, HP 3325B, HP 53131A/132A Synthesizer, 4On the Counter, press Run key, Figure 1-6.Trigger Level Test Setup

Chapter 1 Performance Tests

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

Procedure

1Connect the output of the HP 3325B to Channel 1 of the Counter as shown in Figure 1-6.

1

HP 3325B

HP 53131A/132A Synthesizer

Counter

Channel 1 Channel 2 Output

Figure 1-6. Trigger Level Test Setup2Set the HP 3325B to output a 1 MHz, 80 mVp-p square wave signal.3Set the HP 3325B DC OFFSET to −60 mV.4On the Counter, press Run key.

5Now, increment the dc offset on the HP 3325B by +1 mV until the Counter’s Gate annunciator flashes and continue incrementing until the Counter displays a stable reading of approximately

1 MHz.

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

6Add the upper peak voltage (40 mV) of the 80 mV p-p signal to the offset value in step 5 (For example, −24 mV + 40 mV = 16 mV).

This is the upper hysteresis level.

Record the upper hysteresis level__________ mV.

1-20 Assembly-Level Service Guide