Agilent Technologies 8720E Series Service Guide

6-18 Service Guide
Digital Control Troubleshooting 8719ET/20ET/22ET
Run the Internal Diagnostic Tests 8719ES/20ES/22ES
RF Network Analyzers
Table 6-2 Internal Diagnostic Test with Commentary
Failed Test
Seq.
*
Probable Failed
Assemblies
†
: Comments and
Troubleshooting Hints
0 All Int M See Chapter 4 , “Start
Troubleshooting Here.”
Executes tests 3-11, 13-16,20.
1 Preset M See Chapter 4 , “Start
Troubleshooting Here.”
Executes tests 2-11, 14-16. Runs at
power-on or preset.
2 ROM P,AI CPU board (A7) Repeats on fail; refer to “CPU
Board (A7) Troubleshooting” on
page 6-4
3 CMOS RAM P,AI CPU board (A7) Replace A7.
4 Main DRAM P,AI CPU board (A7) Repeats on fail; replace A7.
5 DSP Wr/Rd P,AI CPU board (A7) Replace A7.
6 DSP RAM P,AI CPU board (A7) Replace A7.
7 DSP ALU P,AI CPU board (A7) Replace A7.
8 DSP Intrpt P,AI CPU board (A7) or
Digital IF (A10)
Remove A10, rerun test. If fail,
replace CPU board (A7). If pass,
replace A10.
9 DIF Control P,AI CPU board (A7) or
Digital IF (A10)
Most likely A7 assembly.
10 DIF
Counter
P,AI Digital IF (A10) or
CPU board (A7) or
Reference (A12)
Check analog bus node 17 for 1
MHz. If correct, A12 is verified;
suspect A10.
11 DSP
Control
P,AI Digital IF (A10) or
CPU board (A7)
Most likely A10.
12 Fr Pan
Wr/Rd
M Front Panel interface (A2) or
Front Panel keyboard (A1)
or CPU board (A7)
Run test 23. If fail, replace A2. If
pass, problem is on bus between A7
and A2 or on A7 assembly.
13 GPIB
(CPU Board)
AI CPU board (A7) Check A7J2 pin 48 for 4 MHz clock
signal. If signal is bad, replace A7.
14 Post-reg P,AI Preregulator (A15) or
Post regulator (A8) or
Destination assembly
See Chapter 5 , “Power Supply
Troubleshooting.”
15 Frac-N Cont P,AI Fractional-N digital (A14) Replace A14.
16 Sweep Trig P,AI Fractional-N digital (A14) or
Digital IF (A10)
Most likely A14
17 ADC Lin M Digital IF (A10) Replace A10.
18 ADC Ofs M Digital IF (A10) Replace A10.
19 ABUS Test M Digital IF (A10) Replace A10.
20 FN Count AI Fractional-N digital (A14) or
Fractional -N analog (A13)
or Digital IF (A10)
Most likely A14 or A13, as previous
tests check A10. See Chapter 7 ,
“Source Troubleshooting.”
* P = part of Preset sequence; AI =part of ALL INTERNAL sequence; M= Manual.
†
in decreasing order of probability.

Agilent Technologies 8720E Series Specifications

General

Brand	Agilent Technologies
Model	8720E Series
Category	Measuring Instruments
Language	English