Service manual

NOTE
See the Agilent E1346A Single Ended Relay Multiplexer User’s Manual for
information on logical address and IRQ settings. If there are no apparent
problems following the visual checks, run the Performance Verification
Tests in Chapter 2 to see if a relay or other component is defective.
Table 4-2. Agilent E1346A Visual Tests/Checks
Test/Check Reference
Designator
Check Action/Notes
Heat Damage - - - - -
- - - - -
- - - - -
Discolored PC boards
Damaged insulation
Evidence of arcing
If there is damage, do not
operate the multiplexer
until you have corrected
the problem.
Switch/Jumper
Settings
- - - - -
SW1
IRQ Level setting
Logical address setting
Factory set at 1
Factory set at 112
Component
Assembly
F1, F2
J1, J2
P1
Fuse continuity
Dirty or bent connector
pins
Dirty or bent connector
pins
Check fuses with
ohmmeter
Straighten/clean pins
Straighten/clean pins
Terminal Block P1
TB1 - TB5
Dirty or bent connector
pins
Loose screw
connections
Straighten/clean pins
Check/tighten connections
Testing the
Multiplexer
You can use the tests and checks in Chapter 2 - Verification Tests and the
information in Table 4-3 to isolate the problem to a relay, to a component,
or to both. See Chapter 3 - Replaceable Parts for locations of mechanical
parts. See the component locator diagram at the end of this chapter for
locations of electrical components.
Table 4-3 shows the relationship between the failing channel number and
the associated channel relay, tree relay, and driver/decoder. Because the
closed channel resistance test always includes two relay contacts, use Table
4-3 to determine if failures of the closed contact resistance test are in logical
groupings. For example, if Test 2-1. Closed Channel Resistance Test failed
for channel 00 alone, replace relay K0, if the test failed for channels 24
through 31, replace relay K90.
Service 4-5