Chapter 5
123
Troubleshooting the Synthesizer Section
Verifying the A9 2nd LO/ Fan Control Board
Verifying the A9 2nd LO/ Fan Control Board
If the Fans Are Not Operating
CAUTION
The power supply may be in thermal shutdown if the instrument has
been operating without the fans running. Allow the instrument to cool
down before troubleshooting.
If all three fans are not operating, suspect a power supply problem or a
defective fan control circuit on the A9 2nd LO/Fan Control assembly.
Refer to
“A5 Power Supply Assembly Description” on page 153
to check
the individual supplies. If the supplies are within specifications, the
most probable cause is a defective A9 board. Refer to
for
assembly replacement procedures.
If only one or two fans are not functioning, and the power supplies are
within specifications, suspect the A9 assembly or a defective fan.
1. Remove the front frame from the instrument. Refer to
for
removal procedures.
2. Refer to
. Measure all of the fan voltages at J3, J4, and J5
on the motherboard.
Figure 5-2
Fan Voltages
Summary of Contents for E4440A
Page 12: ...12 Contents...
Page 13: ...13 1 Overview...
Page 42: ...42 Chapter1 Overview Contacting Agilent Technologies...
Page 43: ...43 2 Overall Troubleshooting...
Page 69: ...69 3 Troubleshooting the RF Section E4440A E4443A E4445A...
Page 89: ...89 4 Troubleshooting the RF Section E4446A E4447A E4448A...
Page 111: ...111 5 Troubleshooting the Synthesizer Section...
Page 125: ...125 6 Troubleshooting the IF Section...
Page 144: ...144 Chapter6 Troubleshooting the IF Section Verifying the A7 Digital IF Board...
Page 145: ...145 7 Troubleshooting the Processor Power Supply and Display...
Page 165: ...165 8 Hardware Options...
Page 184: ...184 Chapter8 Hardware Options Verifying Option 122 or 140 Wide Bandwidth Digitizer...
Page 186: ...186 Chapter8 Hardware Options Verifying Option 122 or 140 Wide Bandwidth Digitizer...
Page 206: ...206 Chapter8 Hardware Options Verifying Option 124 Y Axis Video Out...
Page 207: ...207 9 Block Diagrams...
Page 211: ...Chapter 9 211 Block Diagrams Signal Mnemonics Figure 9 1 Graphic Symbols...
Page 212: ...212 Chapter9 Block Diagrams Overall Block Diagrams Overall Block Diagrams...
Page 214: ...214 Chapter9 Block Diagrams Overall Block Diagrams...
Page 216: ...216 Chapter9 Block Diagrams Overall Block Diagrams...
Page 217: ...Agi l ent MOTHERBOARD E4440 60001 se860a...
Page 218: ...218 Chapter9 Block Diagrams Overall Block Diagrams...
Page 220: ...220 Chapter9 Block Diagrams Overall Block Diagrams...
Page 221: ...221 10 Replaceable Parts Lists and Locations...
Page 252: ...252 Chapter10 Replaceable Parts Lists and Locations Hardware Figure 10 4 Major Assemblies...
Page 256: ...256 Chapter10 Replaceable Parts Lists and Locations Hardware Figure 10 6 YTO Assembly...
Page 267: ...Chapter 10 267 Replaceable Parts Lists and Locations Hardware...
Page 292: ...292 Chapter10 Replaceable Parts Lists and Locations Hardware Figure 10 27 Front Panel Parts...
Page 298: ...298 Chapter10 Replaceable Parts Lists and Locations Hardware Figure 10 32 Rear Frame Hardware...
Page 304: ...304 Chapter10 Replaceable Parts Lists and Locations Hardware...
Page 305: ...305 11 Assembly Replacement Procedures...
Page 383: ...Chapter 11 383 Assembly Replacement Procedures A25 Motherboard Figure 11 47 Bottom Screws...
Page 409: ...409 12 Post Repair Procedures...
Page 429: ...429 13 Firmware Upgrades...
Page 432: ...432 Chapter13 Firmware Upgrades Firmware Upgrades Including Measurement Personality Upgrades...