Verify The Preregulator (A15) - Agilent Technologies 8719ET Service Manual

Power Supply Troubleshooting
If the Red LED of the Preregulator (A15) Is On

Verify the Preregulator (A15)

Verify that the preregulator (A15) is supplying the correct voltages to the post regulator
(A8). Use a voltmeter with a small probe to measure the output voltages of A15W1's plug.
Refer to Table 5-2 and
• If the voltages are not within tolerance, replace A15.
• If the voltages are within tolerance, A15 is verified. Go to
on page 5-11.
Table 5-2 Output Voltages
Pin A15W1P1
(Disconnected)
1
2 +100 to +125
3,4 +22.4 to +33.6
−22.4 to −33.6
5,6
7
8 +9.4 to +14
−9.4 to −14
9,10
11 +32 to +48
12
NOTE: The +5 VD supply must be loaded by one or more assemblies at
all times, or the other voltages will not be correct. It connects to the
motherboard connector A17J3 Pin 4.
5-10
Figure 5-6.
A8J2
(Connected)
Voltages Voltages
N/C N/C
+100 to +125
+17.0 to +18.4
−17.0 to −18.4
N/C +7.4 to +8.0
+7.4 to +8.0
−6.7 to −7.3
+24.6 to +26.6
N/C +24.6 to +26.6
"Check for a Faulty Assembly"
A15
Preregulator
Mnemonic
N/C
(not used)
+18 V
−18 V
N/C
+8 V
−8 V
+25 V
N/C
8719ET/20ET/22ET
8719ES/20ES/22ES
RF Network Analyzers
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