Agilent Technologies 89410A Service Manual page 97

Time/div
Probe Atten
k Using a a high impedance 1:1 oscilloscope probe, check that A91
J6 pin 27B is a 423 ±42 mVp-p signal.
l
Press the following keys:
[channel 2 front BNC]
[channel 1 source]
m Using a high impedance 1:1 oscilloscope probe, check that A91 J6
pin 29B is a 423 ±42 mVp-p signal.
n
If either signal is incorrect, the A35 Analog Source assembly is
probably faulty.
5 Check the frequency sample signals.
a Place the analyzer on the side closest to the display.
b
Remove the bottom cover.
c
].
Press [Preset
d Using a logic probe, check that the TTL signals listed in the
following table are toggling.
e
If a signal is incorrect, the A60 Frequency Reference assembly is
probably faulty.
f
If all signals are correct, the A50 Digital Filter assembly is
probably faulty.
This test does not check the A71 Pass Through assembly. The
Pass Through assembly buffers the signals from the A21 A/D
Converter assembly before they go to the A50 Digital Filter
assembly. There is a separate set of buffers for each channel. The
Pass Through assembly is less likely to fail than the A50 Digital
Filter assembly.
To troubleshoot two channel analyzer failures
200 ns/div
1
Test Location
A91 P6 pin 4
A91 P6 pin 11
A91 P6 pin 16
Troubleshooting the Analyzer
Signal Name
FSAAD
FSA2
FSA1
1-79