Tektronix WFM700 Series, Service Manual

Page: 83 / 194

Performance Verification
WFM700 Series Waveform Monitors Service Manual
2- 51
7. Press the CONFIG button.
8. Touch the Audio Inputs/Outputs soft key and then Next Menu .
9. Touch the AES Connectors soft key and then Input .
10. Press the AUDIO button.
11. Press the INPUT button, then touch Audio In: and select External AES .
12.
Connect the test port of the Return Loss Bridge directly to the
AES 1--2 I/O
connector. Do not use any cables or adapters.
13. Measure the amplitude of the signal on the test oscilloscope. Note this as the
Reflection level.
14. Calculate the return loss with the formula below using the measured values
from steps 6 and 13.
Input Return Loss
20
log
10
Æ
Reference
Reflection
É
15. CHECK that the calculated return loss is >25 dB.
16. Move the return loss bridge to each of the remaining AES I/O connectors
and repeat steps 12 through 15.
17. Disconnect the test setup.
This test verifies that each AES input locks to an input signal.
Performance Requirement.
This test verifies performance characteristics and is
listed in the test record.
1. Connect the digital audio generator unbalanced (UNBAL) output to
AES 1--2 I/O
using a 75
8
cable.
2.
Set the digital audio generator as follows:
Frequency 1 kHz
Output Level --20 dB FS Audio Tone
Sample Frequency 96 kHz
Unbalanced V
p-p
2.000 V (Carrier Level)
Input Amplitude and
Sample Rate Range