Tektronix WFM700 Series, Service Manual

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Performance Verification
2- 50
WFM700 Series Waveform Monitors Service Manual
WFM700 Audio (Option DG) Performance Verification Procedure
The following tests verify that the Audio module (Option DG) for the WFM700
waveform monitor (all models) meets the warranted characteristics listed in the
Specifications section of the WFM700 Series Technical Reference document.
Characteristics with typical specifications (not warranted) are also checked.
This test verifies that the return loss of the AES Inputs and Outputs.
Performance Requirement. This test verifies performance characteristics and is
listed in the test record.
1.
Install the 50
8
N-to-BNC adapter on the sinewave generator output.
2. Connect the RF generator output to the input port of the Return Loss Bridge
using a 50
8
cable.
3. Connect the output of the Return Loss Bridge to the 50
8
input of the test
oscilloscope using a 50
8
cable. Do not connect the test port of the Bridge at
this time.
4.
Set the sinewave generator as follows:
Frequency 6 MHz
Phase Modulation OFF
Frequency Modulation OFF
Output Power +2.0 dBm (0.8 V p-p)
RF Output ON
5. Adjust the test oscilloscope to obtain a stable display of the 6 MHz sine
wave from the RF generator. The following oscilloscope settings normally
provide a usable display.
Vertical Scale 50 mV
Horizontal Scale 100 ns/div
Bandwidth Limit On
6. Measure the amplitude of the signal on the test oscilloscope. Note this
measurement as the reference level.
NOTE
. The reference level should be between 150 mV and 200 mV. Adjust the
output level of the RF generator if necessary to obtain the correct output level.
Return Loss