Z-Mod Sensitivity - Fluke Autoranging CombiScope PM3370B Service Manual

PERFORMANCE TEST

6.3.41 Z-MOD sensitivity

This test checks the sensitivity of the Z modulation facility.
Test equipment:
Fluke 5500A mode: wavegen, wave square (Alternative: function generator PM 5136).
T-piece.
Test set-up:
Settings/procedure and requirements:
1 - Apply a 1 kHz square-wave signal, duty cycle 50%, amplitude between 0 to +2.5V, to input
CH1. Adjust the generator to a signal of 2.5 Vpp with an offset of 1.25V.
2 - Press the AUTOSET key.
3 - Set MTB to 0.5 ms/div.
4 - Set the trace of CH1 in mid position with the CH1 POS control.
5 - Apply the same signal by means of the T-piece to the Z input (rear side).
6 - Adjust TRACE INTENSITY so that only the bottom half of the squarewave is displayed. The
top half must be invisible (0.5 ms light on; 0.5 ms light off).
7 - Decrease the input signal to 0.5 Vpp with an offset of 0.25V.
8 - Set CH1 to 0.5V/division.
9 - Verify that the top half of the square wave is visible at full intensity.
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