Tektronix WFM700 Series, Руководство по обслуживанию

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Performance Verification
WFM700 Series Waveform Monitors Service Manual
2- 33
12. Move the Return Loss Bridge test port from Input A to Input B .
13. Select Input B .
14. Measure the amplitude of the signal on the test oscilloscope. Note this as the
B Reflection level.
15. Calculate the return loss with the formula below using the measured values
from steps 6 and 14.
Input B Return Loss
20
log
10
Æ
Reference
B Reflection
É
16. CHECK that the calculated return loss is >25 dB for Input B.
17. Disconnect the test setup.
This test checks the Jitter Noise Floor.
Typical Operation Check.
This test checks for typical operation. Typical values are
not guaranteed characteristics and are not listed in the test record.
NOTE
. If this test is performed out of sequence or the sequence of tests has been
interrupted (such as power off or input from another module was selected),
perform the steps in this note to prepare the instrument to continue testing.
a. Connect the SD video generator to INPUT B using a 75
8
cable.
b.
Set the SD video generator for a 525-format 100% color bar signal.
c. Press the INPUT button and select Input B .
d. Press the EYE button.
1. Install the 50
8
N-to-BNC adapter on the RF generator output.
2.
Connect the RF generator output to
INPUT A
using a 75
8
cable. Imped-
ance matching is not important for this test.
3. Set the RF generator as follows:
Frequency 741.7582 MHz
Output Level 0 dB
Frequency Modulation OFF
Phase Modulation OFF
RF Output ON
Jitter Noise Floor (WFM7M
only)