Apple Macintosh Powermac Performa 200 Service Manual

Page 1
K
Service Source
Macintosh Classic/
Classic II/Performa 200
Page 2
K
Service Source

Basics

Macintosh Classic/Classic II/
Page 3
Basics Overview - 1

Overview

This manual includes complete repair procedures for the Macintosh Classic, Classic II, and Performa
200.
Figure: Macintosh Classic/Classic II and Performa 200
Page 4
K
Service Source
Specifications
Macintosh Classic/Classic II/
Page 5
Specifications Processor - 1

Processor

Classic CPU

Classic II/Per 200 CPU

Motorola 68000 microprocessor
7.8336 MHz 32-bit internal data bus 256-byte instruction and data caches
Motorola 68030 microprocessor 16 MHz 32-bit internal data bus 256-byte instruction and data caches
Page 6
Specifications Memory - 2

Memory

RAM
Classic: Classic II/Per 200:
ROM

PRAM

Cache Connector

1 MB, expandable to 4 MB (120 ns or faster SIMMs) 2 MB, expandable to 10 MB (120 ns or faster SIMMs)
512K
256 bytes of parameter memory
44-pin connector for optional memory expansion 256K by 4-bit DRAMs Includes two SIMM connectors for additional RAM expansion
Page 7
Specifications Disk Storage - 3

Disk Storage

Floppy Drive

Hard Drive

Classic: Classic II/Per 200:
Internal 1.4 MB floppy drive Optional external 800K or 1.4 MB floppy drive
Optional internal 40 MB hard drive; optional external SCSI drive Internal 40 MB or 80 MB hard drive; optional external SCSI
drive
Page 8
Specifications I/O Interfaces - 4

I/O Interfaces

Floppy Drive

SCSI

Apple Desktop Bus

Serial

Sound

External drive port; DB-19 connector
One SCSI parallel port; DB-25 connector
One Apple Desktop Bus (ADB) port; mini DIN-4 connector
Two RS-422 serial ports; mini DIN-8 connectors
Dual-channel headphone connector Connected to the monophonic sound output Macintosh Classic does not provide true two-channel output
(although stereo jack may be used)
Page 9
Specifications I/O Devices - 5

I/O Devices

Keyboard

Mouse

Classic II/Per 200 Microphone

80 keys, with numeric keypad; ADB connector
Mechanical tracking; ADB connector
Electret, omnidirectional; output voltage is 4 mV, peak to peak, at
normal volume
Page 10
Specifications Sound and Video - 6

Sound and Video

Sound Generator

Classic:

Video Display

Classic II/Per 200:
Four-voice sound with 8-bit digital/analog conversion, using
22-kHz sampling rate
Monophonic, 8-bit digital/analog conversion using 22-kHz
sampling rate; capable of driving stereo headphones or other stereo equipment through the sound jack
9-in. (diagonal) screen; high-resolution, 512 by 342 pixel,
bit-mapped, monochrome display
Page 11
Specifications Electrical - 7

Electrical

Line V oltage

Frequency

Maximum Power

100–120 V AC
47–63 Hz, single phase
100 W
Page 12
Specifications Physical - 8

Physical

Dimensions

Weight

Height: 13.2 in. (33.6 cm) Width: 9.7 in. (24.6 cm) Depth: 11.2 in. (28.5 cm)
16–17.1 lb. (7.3-7.8 kg) not including internal hard drive
Page 13
K
Service Source

Troubleshooting

Macintosh Classic/Classic II/
Page 14
Troubleshooting General/ - 1

General

The Symptom Charts included in this chapter will help you diagnose specific symptoms related to your product. Because cures are listed on the charts in the order of most likely solution, try the first cure first. Verify whether or not the product continues to exhibit the symptom. If the symptom persists, try the next cure. (Note: If you have replaced a module, reinstall the original module before you proceed to the next cure.)
If you are not sure what the problem is, or if the Symptom Charts do not resolve the problem, refer to the Flowchart for the product family.
For additional assistance, contact Apple Technical Support.
Page 15
Troubleshooting Symptom Charts/Video - 2

Symptom Charts

Video

Screen is dark; audio and drive operate
Screen is bright and audio is present, but no video information is visible
1 Readjust brightness (see Adjustments). 2 Readjust contrast (see Adjustments). 3 Check yoke cable connection. 4 Replace power/sweep board. 5 Replace logic board. Retain customer’s SIMMs. 6 Replace CRT.
1 Replace power/sweep board. 2 Replace logic board. Retain customer’s SIMMs.
Page 16
Troubleshooting Symptom Charts/Video
(Continued)
- 3
Screen is dark; fan is not running
Single vertical line is displayed
Single horizontal line is displayed
Vertical bars or stripes are displayed
Video
Replace power/sweep board.
1 Replace power/sweep board. 2 Replace logic board. Retain customer’s SIMMs. 3 Replace CRT.
1 Replace power/sweep board. 2 Replace logic board. Retain customer’s SIMMs. 3 Replace CRT.
1 Replace power/sweep board. 2 Replace logic board. Retain customer’s SIMMs.
(Continued)
Page 17
Troubleshooting Symptom Charts/Video
(Continued)
- 4
Video
Horizontal bars or stripes are displayed
White dot is displayed in center of screen
Screen jitters 1 Move computer away from adjacent monitors or other
1 Replace power/sweep board. 2 Replace logic board. Retain customer’s SIMMs.
1 Verify that yoke cable is connected. 2 Replace power/sweep board. 3 Replace CRT.
2 Replace power/sweep board.
(Continued)
electrical equipment that may cause interference.
Page 18
Troubleshooting Symptom Charts/Video
(Continued)
- 5
After replacement of failed hard drive, video distortion appears in upper and lower corners of screen
Video
Check whether hard drive replacement was like-for-like. If not, install a like drive.
(Continued)
Page 19
Troubleshooting Symptom Charts/Floppy Drives - 6

Floppy Drives

Audio and video are present, but internal floppy drive does not operate
External floppy drive does not operate
Disk ejects; display shows icon with blinking “X”
1 Replace bad disk with known-good disk. 2 Replace floppy drive cable. 3 Replace floppy drive. 4 Replace logic board. Retain customer’s SIMMs.
1 Replace bad disk with known-good disk. 2 Be sure external floppy drive is placed on right side of
computer. 3 Replace external floppy drive. 4 Replace logic board. Retain customer’s SIMMs.
1 Replace bad disk with known-good system disk. 2 Replace floppy drive. 3 Replace logic board. Retain customer’s SIMMs.
Page 20
Troubleshooting Symptom Charts/Floppy Drives
(Continued)
- 7
Floppy Drives
Unable to insert disk all the way
Does not eject disk 1 Insert opened paper clip into hole beside floppy drive.
Internal floppy drive runs continuously
1 Insert opened paper clip into hole beside floppy drive. 2 Switch off system and hold mouse button down while
switching system on (to complete eject cycle). 3 Replace floppy drive.
2 Switch off system and hold mouse button down while
switching system on (to complete eject cycle). 3 Replace floppy drive.
1 Replace bad disk with known-good disk. 2 Replace floppy drive. 3 Replace logic board. Retain customer’s SIMMs. 4 Replace floppy drive cable.
(Continued)
Page 21
Troubleshooting Symptom Charts/Hard Drives - 8

Hard Drives

Internal or external hard drive does not operate
Works with internal or external SCSI device but does not work with both.
1 Verify that SCSI loopback card is not attached. 2 Check that internal SCSI terminator is positioned in
connector properly. 3 Verify that internal hard drive has all three terminating
resistor packs on circuit board. 4 Replace hard drive data cable. 5 Replace hard drive. 6 Replace logic board. Retain customer’s SIMMs.
1 Verify that SCSI device ID switch setting on external device
is higher than 0. Also verify that ID switch setting on
external SCSI device does not duplicate ID switch settings on
any other attached external SCSI devices. 2 Replace terminator on external SCSI device. 3 Verify that terminator is installed on internal SCSI drive. 4 Replace SCSI select cable.
Page 22
Troubleshooting Symptom Charts/Peripheral - 9

Peripheral

Cursor does not move 1 Check mouse connection.
2 If mouse was connected to keyboard, connect it to rear ADB
port instead. If mouse works, replace keyboard. 3 If mouse does not work in any ADB port, replace mouse. 4 Replace logic board. Retain customer’s SIMMs.
Cursor moves, but clicking the mouse button has no effect
1 Replace mouse. 2 Replace logic board. Retain customer’s SIMMs.
Page 23
Troubleshooting Symptom Charts/Peripheral
(Continued)
- 10
Cannot double-click to open application, disk, or server
No response to any key on keyboard
Peripheral
1 Remove extra system files on hard drive. 2 Clear parameter RAM. Hold down <Shift> <Option>
<Command> keys and select Control Panel from Apple pull-
down menu. Reset mouse controls. 3 If mouse was connected to keyboard, connect it to rear ADB
port instead. If mouse works, replace keyboard. 4 If mouse does not work in any ADB port, replace mouse. 5 Replace logic board. Retain customer’s SIMMs.
1 Check keyboard connection to ADB port. 2 Replace keyboard cable. 3 Replace keyboard. 4 Replace logic board. Retain customer’s SIMMs.
(Continued)
Page 24
Troubleshooting Symptom Charts/Peripheral
(Continued)
- 11
Known-good ImageWriter or ImageWriter II does not print
Known-good LaserWriter does not print.
Peripheral
1 Make sure that Chooser and Control Panel are set correctly. 2 Replace printer driver and system software with known-
good. 3 Replace printer interface cable. 4 Replace logic board. Retain customer’s SIMMs.
1 Make sure that Chooser and Control Panel are set correctly. 2 Replace printer driver and system software with known-
good. 3 Refer to Networks manual.
(Continued)
Page 25
Troubleshooting Symptom Charts/Miscellaneous - 12

Miscellaneous

Clicking, chirping, or thumping sound
Smoke/odor Replace power/sweep board.
No video, no audio, and no drive operation
1 Verify that logic board power cable is connected at J12 on
logic board. 2 Replace power/sweep board. 3 Replace logic board. Retain customer’s SIMMs.
1 Connect power cord. 2 Switch power on. 3 Replace power cord. 4 Replace fuse. 5 Replace power/sweep board. 6 Replace logic board. Retain customer’s SIMMs.
Page 26
Troubleshooting Symptom Charts/Miscellaneous
(Continued)
- 13
Miscellaneous
“Sad Macintosh” icon 1 Replace bad disk with known-good disk.
2 Verify that jumper on memory expansion board is configured
correctly for “SIMMs” or “No SIMMs.” (See “Memory
Upgrade” in Additional Procedures.) 3 On 4 MB Macintosh Classic, confirm SIMMs used are eight-
chip SIMMs. (See Memory manual.) Any 1 MB SIMMs with
fewer than eight chips won’t work in the Macintosh Classic. 4 On Macintosh Classic, replace optional memory expansion
board; on Macintosh Classic II/Performa 200, replace
optional SIMMs in two SIMMs slots on logic board. 5 Replace logic board. Retain customer’s SIMMs.
(Continued)
Page 27
Troubleshooting Symptom Charts/Miscellaneous
(Continued)
- 14
Screen shows “Sad Macintosh” icon and black vertical lines; screeching sound
Miscellaneous
1 Verify that jumper on memory expansion board is configured
correctly for “SIMMs” or “No SIMMs.” (See “Memory
Upgrade” in Upgrades.) 2 On 4 MB Macintosh Classic, confirm SIMMs used are eight-
chip SIMMs. (See Memory manual.) Any 1 MB SIMMs with
fewer than eight chips won’t work in the Macintosh Classic. 3 On Macintosh Classic, replace optional memory expansion
board; on Macintosh Classic II/Performa 200, replace
optional SIMMs in two SIMMs slots on logic board. 4 Replace logic board. Retain customer’s SIMMs.
(Continued)
Page 28
Troubleshooting Symptom Charts/Miscellaneous
(Continued)
- 15
Miscellaneous
No power 1 Connect power cord.
2 Switch power on. 3 Replace power cord. 4 Replace fuse. 5 Replace power/sweep board. 6 Replace logic board. Retain customer’s SIMMs.
(Continued)
Page 29
K
Service Source

T ak e Apart

Macintosh Classic/Classic II/
Page 30
Take Apart Cover - 1

Cover

No preliminary steps are required before you begin this procedure.
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 31
Take Apart Cover - 2
1 Using a Torx
screwdriver, remove the four case screws. Using a case spreader or pull-apart tool, separate the cover from the chassis.
2 Carefully lift the cover
and set it aside.
±
Warning:
the metal chassis may be sharp. When moving the computer with the cover off, be sure to handle the chassis carefully.
The edges of
Page 32
Take Apart Cover - 3
Note:
When replacing the cover, be sure to install the two black case screws in the bottom of the cover and the two silver-colored case screws in the top of the cover.
Page 33
Take Apart Power/Sweep Board - 4

Power/Sweep Board

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the anode cap
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Caution:
To prevent ESD
Page 34
Take Apart Power/Sweep Board - 5
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Page 35
Take Apart Power/Sweep Board - 6
1 Using a Torx
screwdriver, remove the screw that secures the ground wire to the upper corner of the CRT.
2 Carefully pull off the
video board from the neck of the CRT.
Note:
If sealant holds the board in place, cut the sealant with an art knife.
Page 36
Take Apart Power/Sweep Board - 7
3 Remove the logic board
power cable from the logic board. Remove the Phillips screws that secure the power/sweep bracket to the chassis and pull the board slightly away from the chassis.
Note:
Most power/sweep brackets are secured by two screws; however, some are secured by three.
Page 37
Take Apart Power/Sweep Board - 8
5 Remove the following
cable connectors from the power/sweep board:
• Yoke cable
• Fan cable
• Hard drive power
cable (if present)
Page 38
Take Apart Power/Sweep Board - 9
6 Lift the board free.
Page 39
Take Apart Power/Sweep Board - 10
Note:
The two versions of the power/sweep board, Rev A and Rev B, are functionally equivalent, but they are not interchangeable.
In addition, a Rev A power/ sweep board must be used with a Rev A CRT yoke assembly and a Rev A or Rev B cover. A Rev B power/ sweep board must be used with a Rev B CRT yoke assembly and a Rev B cover.
Page 40
Take Apart Power/Sweep Board - 11
To identify compatible versions of the power/sweep board, CRT assembly, and cover, examine the CRT yoke connector. Power/sweep board Rev A has plastic sleeves surrounding the prongs; the prongs are exposed on power/sweep board Rev B.
Page 41
Take Apart Logic Board - 12

Logic Board

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the memory
expansion board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 42
Take Apart Logic Board - 13
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 43
Take Apart Logic Board - 14
1 Remove the following
cable connectors from
the logic board:
• Logic board power cable
• Floppy drive cable
• Hard drive data cable (if present)
Hard Drive
Data Cable
Floppy Drive Cable
Page 44
Take Apart Logic Board - 15
2 Grasp the logic board by
the corners and slide it straight up and out of the chassis.
Replacement Note:
the SIMMs from the defective logic board and install them in the replacement logic board. (See Memory manual.)
Remove
Page 45
Take Apart Hard Drive - 16

Hard Drive

Before you begin:
• Remove the cover
• Discharge the CRT
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 46
Take Apart Hard Drive - 17
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 47
Take Apart Hard Drive - 18
1 Disconnect the hard
drive data cable from the logic board.
2 Disconnect the hard
drive power cable from the power/sweep board.
Hard Drive Power Cable
Logic Board
Hard Drive Data Cable
Page 48
Take Apart Hard Drive - 19
3 Remove the two Phillips
screws that secure the hard drive housing to the floppy drive housing and lift out the hard drive assembly.
Replacement Note:
are removing a hard drive from the system but not installing a new one, install a SCSI terminator on the logic board SCSI connector. To insert the terminator, line up the white key icon with the notch in the cable connector.
If you
Page 49
Take Apart Hard Drive - 20
Replacement Note:
information on removing the hard drive from the carrier and returning drives, cables, and carriers to Apple, refer to Hardware/ Service Manuals/ SCSI Hard Drives Manual.
For
Page 50
Take Apart Floppy Drive - 21

Floppy Drive

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the hard drive
• Remove the logic board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Caution:
To prevent ESD
Page 51
Take Apart Floppy Drive - 22
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Page 52
Take Apart Floppy Drive - 23
1 Remove the four Phillips
screws that secure the floppy drive housing to the bottom of the chassis.
Page 53
Take Apart Floppy Drive - 24
2 Lift out the floppy drive
mechanism.
Replacement Note:
you install a replacement
1.4 MB SuperDrive, you must remove the dust shield.
Before
Page 54
Take Apart Fan - 25
Fan
Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the anode cap
• Remove the power/sweep board
±
Fan
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 55
Take Apart Fan - 26
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 56
Take Apart Fan - 27
1 Using a small, stump-
handled Phillips screwdriver, remove the two screws that mount the fan to the chassis.
2 Lift out the fan.
Page 57
Take Apart CRT - 28
CRT
Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the anode cap
• Remove the power/sweep board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 58
Take Apart CRT - 29
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 59
Take Apart CRT - 30
1 Remove the three Torx
screws from the corners of the CRT.
2 Carefully lift the CRT
free from the bezel.
Note:
The CRT yoke assembly must be compatible with the power/ sweep assembly, which is available in two versions, Rev A and Rev B. CRT yoke assembly Rev A requires power/sweep board Rev A. CRT yoke assembly Rev B requires power/sweep board Rev B.
Page 60
Take Apart CRT - 31
Refer to “Power/Sweep Board” in Take Apart to identify CRT and power/ sweep revisions and to verify compatibility.
Page 61
Take Apart Chassis & Front Bezel - 32

Chassis & Front Bezel

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the anode cap
• Remove the power/sweep
board
• Remove the memory
expansion board
• Remove the logic board
• Remove the hard drive
• Remove the floppy drive
• Remove the fan
Page 62
Take Apart Chassis & Front Bezel - 33
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 63
Take Apart Chassis & Front Bezel - 34
1 Remove the four Torx
screws from the front bezel.
2 Lift out the metal
chassis.
Page 64
Take Apart Chassis & Front Bezel - 35
3 Remove the three Torx
screws from the corner of the CRT, and remove the CRT.
Page 65
Take Apart Fuse - 36

Fuse

Before you begin:
• Remove the cover
• Discharge the CRT
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 66
Take Apart Fuse - 37
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Using a fuse puller or small flat-blade screwdriver, carefully remove the fuse from its holder.
To prevent ESD
Page 67
K
Service Source

Upgrades

Macintosh Classic/Classic II/
Page 68
Upgrades Memory Exp. Bd. - 1

Memory Exp. Bd.

Before you begin:
• Remove the cover
• Discharge the CRT
±
Memory Expansion
Board
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 69
Upgrades Memory Exp. Bd. - 2
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 70
Upgrades Memory Exp. Bd. - 3
Note:
The memory expansion board is an option for the Macintosh Classic only. It contains 1 MB of soldered RAM plus one pair of SIMM connectors.
Carefully slide the memory expansion board up to free it from the logic board and the chassis.
Page 71
Upgrades Memory Upgrade - 4

Memory Upgrade

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the memory
expansion board
±
Memory Expansion
Board
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 72
Upgrades Memory Upgrade - 5
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 73
Upgrades Memory Upgrade - 6
Note:
The memory expansion board is an option for the Macintosh Classic only. It contains 1 MB of soldered RAM plus one pair of SIMM connectors. You can
SIMM Connectors
upgrade the system further by adding two 256K or two 1 MB SIMMs to the memory expansion board and moving the jumper. You must use 120-ns (or faster) SIMMs.
Jumper
1 MB soldered RAM
Page 74
Upgrades Memory Upgrade - 7
Note:
Install the memory board without additional SIMMs for a 1 MB RAM upgrade. Install two 256K SIMMs onto the memory expansion board for a 2.5
SIMM Connectors
MB RAM upgrade or two 1 MB SIMMs for a 4 MB RAM upgrade.
1 Install the SIMMs in the
SIMM slots on the
Jumper
memory expansion board.
2 Position the jumper as
1 MB soldered RAM
shown.
Page 75
Upgrades Classic II Upgrade - 8

Classic II Upgrade

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the logic board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Caution:
damage to components, wear
To prevent ESD
Page 76
Upgrades Classic II Upgrade - 9
a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Page 77
Upgrades Classic II Upgrade - 10
Note:
A Macintosh Classic II upgrade kit upgrades a Macintosh Classic to a Macintosh Classic II. The upgrade kit includes a Classic II logic board, a Classic II cover, a microphone, and an accessory kit.
Page 78
Upgrades Classic II Upgrade - 11
Caution:
connections to the sound output and sound input ports are correct. Inserting the wrong equipment into the wrong port could damage the Macintosh Classic II or external equipment.
1 Install the Macintosh
Take care that the
Classic II logic board.
Page 79
Upgrades Classic II Upgrade - 12
Serial Number
2 Install the Classic II
cover.
3 Read the customer’s
original serial number from the label on the back of the old rear housing and record the number with indelible ink or engrave it onto the new rear housing.
Page 80
K
Service Source

Additional Procedures

Macintosh Classic/Classic II/
Page 81
Additional Procedures Battery Verification - 1

Battery Verification

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the logic board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Caution:
To prevent ESD
Page 82
Additional Procedures Battery Verification - 2
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Page 83
Additional Procedures Battery Verification - 3
±
Warning:
discarded improperly, the lithium battery in the computer could explode. Review battery handling and disposal instructions in Bulletins/Safety.
1 Set the voltmeter range
to the10 volts DC scale.
2 Hold the positive probe
of the voltmeter to the positive “+” side of the battery. Hold the ground probe of the voltmeter to the negative (-) side of the battery.
If handled or
Page 84
Additional Procedures Battery Verification - 4
3 If the battery voltage is
below 3.0 volts, replace the battery. See “Battery Replacement” in this chapter.
Page 85
Additional Procedures Battery Replacement - 5

Battery Replacement

Before you begin:
• Remove the cover
• Discharge the CRT
• Remove the logic board
±
Warning:
contains high voltage and a high-vacuum picture tube. To prevent serious personal injury or equipment damage, review CRT safety and discharge instructions in Bulletins/Safety.
This product
Page 86
Additional Procedures Battery Replacement - 6
Caution:
damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
To prevent ESD
Page 87
Additional Procedures Battery Replacement - 7
±
Warning:
discarded improperly, the lithium battery in the computer could explode. Review battery handling and disposal instructions in Bulletins/Safety.
1 Pull the old battery out
of the battery holder.
2 Replacement Note:
Orient the new battery so that the end marked “+” matches the “+” on the logic board, and insert the battery into the battery holder.
If handled or
Page 88
Additional Procedures Battery Replacement - 8
Note:
For information about properly disposing of the old battery, refer to battery disposal instructions in Bulletins/Safety.
Page 89
K
Service Source

Adjustments

Macintosh Classic/Classic II/
Page 90
Adjustments Light Meter Setup - 1

Light Meter Setup

This topic covers setup for three light meter models: R77, L-248, and 246. Model R77 (Apple part number 076-0310) is the newest model available.

Model R77

The R77 light meter is capable of reading luminance from 10 to 1,000 footcandles (fc).
Before you begin, remove the 10X multiplier plate
Page 91
Adjustments Light Meter Setup - 2
from the lens.
Three scales are shown on the light meter:
• 200-1000 fc
• 50-250 fc
• 10-50 fc
Because display screen luminance typically ranges from 10 to 50 fc, take readings from the bottom scale only.
Page 92
Adjustments Light Meter Setup - 3
To measure a display screen’s luminance,
1 Set the scale switch to
the bottom position (to set up the 10-50 fc scale).
2 Place the lens against the
middle of the screen and read the bottom scale.
Note:
When the light meter is not in use, slide the scale switch to its top position, and store the meter in its protective case.
Important:
light meter is giving false
If you suspect the
Page 93
Adjustments Light Meter Setup - 4
readings, verify the readings with a known-good light meter or photometer. Also check the age of the R77 light meter by its four-digit manufacturing date stamp (such as 0398 for March
1998).
Caution:
meter can permanently damage its accuracy. A shock-damaged meter might read incorrectly or its pointer may not drop to zero.
Dropping the
Page 94
Adjustments Light Meter Setup - 5
Side Switch
Scale
Lens
Read Button
Red Area

Model L-248

1 Press the red button on
the back of the light meter. If the reading is out of the red area, replace the battery.
2 Move the side switch to
its lower position so that the scale reads 2 through
10.
3 Uncover the lens of the
meter.
4 Place the lens against the
middle of the screen and press the read button to read the scale.
Page 95
Adjustments Light Meter Setup - 6

Model 246

1 Remove the metal slide,
Lens
if installed, from the top of the light meter.
Swivel Head
Scale
2 Install the white lens
with the red dot.
3 Rotate the swivel head
so the lens of the meter faces the monitor.
4 Place the lens against the
middle of the screen and read the scale.
Page 96
Adjustments Video - 7

Video

Note:
After you replace the CRT or power/sweep board, you may need to perform video adjustments.
1
Caution:
must make adjustments from the rear of the computer, position a mirror to view the computer screen.
Because you
Page 97
Adjustments Video - 8
2 Using a small flat-blade
screwdriver, depress the center tab and lift out the service door.
Page 98
Adjustments Video - 9

Brightness & Contrast

Contrast (PL2)
Brightness
(PL4)
Important:
light meters may differ between models. Please note the type of meter you are using (Model R77, L-248, or 246) before making an adjustment. (See “Light Meter Setup.”)
Note:
has been on for at least 30 minutes.
1 Run the Display Service
Utility from the Utilities folder on the MacTest Pro CD.
Readings from
Be sure the computer
Page 99
Adjustments Video - 10
2 From the pattern
selections screen, select the Full brightness screen.
3 Hold the light meter
lens against the center of the screen.
4 Using an insulated flat-
blade screwdriver, adjust the contrast control until you measure luminance at 40 foot lamberts (± 3 foot lamberts), which on the light meter is
• Model R77: 29 on the bottom scale
Page 100
Adjustments Video - 11
• Model L-248: 10 to 11 on the 10-18 scale
• Model 246: 29 on the red scale
Important:
light meter tolerance can vary. If you doubt your meter’s accuracy, verify the readings with a known-good light meter or photometer.
5 Press a key to return to
the pattern selections screen. Select the Half brightness screen.
Over time,
Loading...