K Service Source Macintosh Classic/ Classic II/Performa 200
K Service Source Basics Macintosh Classic/Classic II/ Performa 200
Basics Overview - 1 Overview This manual includes complete repair procedures for the Macintosh Classic, Classic II, and Performa 200.
K Service Source Specifications Macintosh Classic/Classic II/ Performa 200
Specifications Processor - 1 Processor Classic CPU Classic II/Per 200 CPU Motorola 68000 microprocessor 7.
Specifications Memory - 2 Memory RAM Classic: Classic II/Per 200: 1 MB, expandable to 4 MB (120 ns or faster SIMMs) 2 MB, expandable to 10 MB (120 ns or faster SIMMs) ROM 512K PRAM 256 bytes of parameter memory Cache Connector 44-pin connector for optional memory expansion 256K by 4-bit DRAMs Includes two SIMM connectors for additional RAM expansion
Specifications Disk Storage - 3 Disk Storage Floppy Drive Internal 1.4 MB floppy drive Optional external 800K or 1.
Specifications I/O Interfaces - 4 I/O Interfaces Floppy Drive External drive port; DB-19 connector SCSI One SCSI parallel port; DB-25 connector Apple Desktop Bus One Apple Desktop Bus (ADB) port; mini DIN-4 connector Serial Two RS-422 serial ports; mini DIN-8 connectors Sound 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)
Specifications I/O Devices - 5 I/O Devices Keyboard 80 keys, with numeric keypad; ADB connector Mouse Mechanical tracking; ADB connector Classic II/Per 200 Microphone Electret, omnidirectional; output voltage is 4 mV, peak to peak, at normal volume
Specifications Sound and Video - 6 Sound and Video Sound Generator Classic: Four-voice sound with 8-bit digital/analog conversion, using 22-kHz sampling rate Video Display Classic II/Per 200: 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.
Specifications Electrical - 7 Electrical Line Voltage 100–120 V AC Frequency 47–63 Hz, single phase Maximum Power 100 W
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.
K Service Source Troubleshooting Macintosh Classic/Classic II/ Performa 200
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.
Troubleshooting Symptom Charts/Video - 2 Symptom Charts Video Screen is dark; audio and drive operate 1 2 3 4 5 6 Readjust brightness (see Adjustments). Readjust contrast (see Adjustments). Check yoke cable connection. Replace power/sweep board. Replace logic board. Retain customer’s SIMMs. Replace CRT. Screen is bright and audio is present, but no video information is visible 1 2 Replace power/sweep board. Replace logic board. Retain customer’s SIMMs.
Troubleshooting Symptom Charts/Video (Continued) - 3 Video (Continued) Screen is dark; fan is not running Replace power/sweep board. Single vertical line is displayed 1 2 3 Replace power/sweep board. Replace logic board. Retain customer’s SIMMs. Replace CRT. Single horizontal line is displayed 1 2 3 Replace power/sweep board. Replace logic board. Retain customer’s SIMMs. Replace CRT. Vertical bars or stripes are displayed 1 2 Replace power/sweep board. Replace logic board.
Troubleshooting Symptom Charts/Video (Continued) - 4 Video (Continued) Horizontal bars or stripes are displayed 1 2 Replace power/sweep board. Replace logic board. Retain customer’s SIMMs. White dot is displayed in center of screen 1 2 3 Verify that yoke cable is connected. Replace power/sweep board. Replace CRT. Screen jitters 1 Move computer away from adjacent monitors or other electrical equipment that may cause interference. Replace power/sweep board.
Troubleshooting Symptom Charts/Video (Continued) - 5 Video (Continued) After replacement of failed hard drive, video distortion appears in upper and lower corners of screen Check whether hard drive replacement was like-for-like. If not, install a like drive.
Troubleshooting Symptom Charts/Floppy Drives - 6 Floppy Drives Audio and video are present, but internal floppy drive does not operate 1 2 3 4 Replace bad disk with known-good disk. Replace floppy drive cable. Replace floppy drive. Replace logic board. Retain customer’s SIMMs. External floppy drive does not operate 1 2 3 4 Replace bad disk with known-good disk. Be sure external floppy drive is placed on right side of computer. Replace external floppy drive. Replace logic board.
Troubleshooting Symptom Charts/Floppy Drives (Continued) - 7 Floppy Drives (Continued) Unable to insert disk all the way 1 2 3 Does not eject disk Internal floppy drive runs continuously 1 2 Insert opened paper clip into hole beside floppy drive. Switch off system and hold mouse button down while switching system on (to complete eject cycle). Replace floppy drive. 3 Insert opened paper clip into hole beside floppy drive.
Troubleshooting Symptom Charts/Hard Drives - 8 Hard Drives Internal or external hard drive does not operate 1 2 3 4 5 6 Works with internal or external SCSI device but does not work with both. 1 2 3 4 Verify that SCSI loopback card is not attached. Check that internal SCSI terminator is positioned in connector properly. Verify that internal hard drive has all three terminating resistor packs on circuit board. Replace hard drive data cable. Replace hard drive. Replace logic board.
Troubleshooting Symptom Charts/Peripheral - 9 Peripheral Cursor does not move Cursor moves, but clicking the mouse button has no effect 1 2 3 4 Check mouse connection. If mouse was connected to keyboard, connect it to rear ADB port instead. If mouse works, replace keyboard. If mouse does not work in any ADB port, replace mouse. Replace logic board. Retain customer’s SIMMs. 1 2 Replace mouse. Replace logic board. Retain customer’s SIMMs.
Troubleshooting Symptom Charts/Peripheral (Continued) - 10 Peripheral (Continued) Cannot double-click to open application, disk, or server 1 2 4 5 Remove extra system files on hard drive. Clear parameter RAM. Hold down
Troubleshooting Symptom Charts/Peripheral (Continued) - 11 Peripheral (Continued) Known-good ImageWriter or ImageWriter II does not print 1 2 Known-good LaserWriter does not print. 1 2 3 4 3 Make sure that Chooser and Control Panel are set correctly. Replace printer driver and system software with knowngood. Replace printer interface cable. Replace logic board. Retain customer’s SIMMs. Make sure that Chooser and Control Panel are set correctly.
Troubleshooting Symptom Charts/Miscellaneous - 12 Miscellaneous Clicking, chirping, or thumping sound 1 Smoke/odor Replace power/sweep board. No video, no audio, and no drive operation 1 2 3 4 5 6 2 3 Verify that logic board power cable is connected at J12 on logic board. Replace power/sweep board. Replace logic board. Retain customer’s SIMMs. Connect power cord. Switch power on. Replace power cord. Replace fuse. Replace power/sweep board. Replace logic board. Retain customer’s SIMMs.
Troubleshooting Symptom Charts/Miscellaneous (Continued) - 13 Miscellaneous (Continued) “Sad Macintosh” icon 1 2 3 4 5 Replace bad disk with known-good disk. Verify that jumper on memory expansion board is configured correctly for “SIMMs” or “No SIMMs.” (See “Memory Upgrade” in Additional Procedures.) On 4 MB Macintosh Classic, confirm SIMMs used are eightchip SIMMs. (See Memory manual.) Any 1 MB SIMMs with fewer than eight chips won’t work in the Macintosh Classic.
Troubleshooting Symptom Charts/Miscellaneous (Continued) - 14 Miscellaneous (Continued) Screen shows “Sad Macintosh” icon and black vertical lines; screeching sound 1 2 3 4 Verify that jumper on memory expansion board is configured correctly for “SIMMs” or “No SIMMs.” (See “Memory Upgrade” in Upgrades.) On 4 MB Macintosh Classic, confirm SIMMs used are eightchip SIMMs. (See Memory manual.) Any 1 MB SIMMs with fewer than eight chips won’t work in the Macintosh Classic.
Troubleshooting Symptom Charts/Miscellaneous (Continued) - 15 Miscellaneous (Continued) No power 1 2 3 4 5 6 Connect power cord. Switch power on. Replace power cord. Replace fuse. Replace power/sweep board. Replace logic board. Retain customer’s SIMMs.
K Service Source Take Apart Macintosh Classic/Classic II/ Performa 200
Take Apart Cover - 1 Cover No preliminary steps are required before you begin this procedure. Warning: This product 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.
Take Apart Cover - 2 1 2 Using a Torx screwdriver, remove the four case screws. Using a case spreader or pull-apart tool, separate the cover from the chassis. Carefully lift the cover and set it aside. Warning: The edges of the metal chassis may be sharp. When moving the computer with the cover off, be sure to handle the chassis carefully.
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.
Take Apart Power/Sweep Board - 4 Power/Sweep Board Before you begin: • Remove the cover • Discharge the CRT • Remove the anode cap This product 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.
Take Apart Power/Sweep Board - 5 damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart Power/Sweep Board - 6 1 2 Using a Torx screwdriver, remove the screw that secures the ground wire to the upper corner of the CRT. 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.
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.
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)
Take Apart Power/Sweep Board - 9 6 Lift the board free.
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.
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.
Take Apart Logic Board - 12 Logic Board Before you begin: • Remove the cover • Discharge the CRT • Remove the memory expansion board Warning: This product 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.
Take Apart Logic Board - 13 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart Logic Board - 14 1 Hard Drive Data Cable Floppy Drive Cable Remove the following cable connectors from the logic board: • Logic board power cable • Floppy drive cable • Hard drive data cable (if present)
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: Remove the SIMMs from the defective logic board and install them in the replacement logic board. (See Memory manual.
Take Apart Hard Drive - 16 Hard Drive Before you begin: • Remove the cover • Discharge the CRT Warning: This product 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.
Take Apart Hard Drive - 17 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart Hard Drive - 18 1 2 Hard Drive Power Cable Logic Board Hard Drive Data Cable Disconnect the hard drive data cable from the logic board. Disconnect the hard drive power cable from the power/sweep board.
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: If you 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.
Take Apart Hard Drive - 20 Replacement Note: For 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.
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: This product 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.
Take Apart Floppy Drive - 22 damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart Floppy Drive - 23 1 Remove the four Phillips screws that secure the floppy drive housing to the bottom of the chassis.
Take Apart Floppy Drive - 24 2 Lift out the floppy drive mechanism. Replacement Note: Before you install a replacement 1.4 MB SuperDrive, you must remove the dust shield.
Take Apart Fan - 25 Fan Before you begin: • Remove the cover • Discharge the CRT • Remove the anode cap • Remove the power/sweep board This product 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.
Take Apart Fan - 26 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart Fan - 27 1 2 Using a small, stumphandled Phillips screwdriver, remove the two screws that mount the fan to the chassis. Lift out the fan.
Take Apart CRT - 28 CRT Before you begin: • Remove the cover • Discharge the CRT • Remove the anode cap • Remove the power/sweep board This product 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.
Take Apart CRT - 29 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Take Apart CRT - 30 1 2 Remove the three Torx screws from the corners of the CRT. 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.
Take Apart CRT - 31 Refer to “Power/Sweep Board” in Take Apart to identify CRT and power/ sweep revisions and to verify compatibility.
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
Take Apart Chassis & Front Bezel - 33 This product 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.
Take Apart Chassis & Front Bezel - 34 1 2 Remove the four Torx screws from the front bezel. Lift out the metal chassis.
Take Apart Chassis & Front Bezel - 35 3 Remove the three Torx screws from the corner of the CRT, and remove the CRT.
Take Apart Fuse - 36 Fuse Before you begin: • Remove the cover • Discharge the CRT Warning: This product 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.
Take Apart Fuse - 37 Caution: To prevent ESD 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.
K Service Source Upgrades Macintosh Classic/Classic II/ Performa 200
Upgrades Memory Exp. Bd. - 1 Memory Exp. Bd. Before you begin: • Remove the cover • Discharge the CRT Warning: This product 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.
Upgrades Memory Exp. Bd. - 2 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
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.
Upgrades Memory Upgrade - 4 Memory Upgrade Before you begin: • Remove the cover • Discharge the CRT • Remove the memory expansion board Warning: This product 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.
Upgrades Memory Upgrade - 5 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Upgrades Memory Upgrade - 6 SIMM Connectors Jumper 1 MB soldered RAM 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 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.
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 MB RAM upgrade or two 1 MB SIMMs for a 4 MB RAM upgrade. SIMM Connectors 1 Jumper 1 MB soldered RAM 2 Install the SIMMs in the SIMM slots on the memory expansion board. Position the jumper as shown.
Upgrades Classic II Upgrade - 8 Classic II Upgrade Before you begin: • Remove the cover • Discharge the CRT • Remove the logic board This product 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.
Upgrades Classic II Upgrade - 9 a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
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.
Upgrades Classic II Upgrade - 11 Caution: Take care that the 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 Classic II logic board.
Upgrades Classic II Upgrade - 12 Serial Number 2 3 Install the Classic II cover. 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.
K Service Source Additional Procedures Macintosh Classic/Classic II/ Performa 200
Additional Procedures Battery Verification - 1 Battery Verification Before you begin: • Remove the cover • Discharge the CRT • Remove the logic board This product 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.
Additional Procedures Battery Verification - 2 damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Additional Procedures Battery Verification - 3 If handled or discarded improperly, the lithium battery in the computer could explode. Review battery handling and disposal instructions in Bulletins/Safety. ±Warning: 1 2 Set the voltmeter range to the10 volts DC scale. 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.
Additional Procedures Battery Verification - 4 3 If the battery voltage is below 3.0 volts, replace the battery. See “Battery Replacement” in this chapter.
Additional Procedures Battery Replacement - 5 Battery Replacement Before you begin: • Remove the cover • Discharge the CRT • Remove the logic board This product 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.
Additional Procedures Battery Replacement - 6 Caution: To prevent ESD damage to components, wear a grounding wriststrap. Never use a grounding wriststrap until after discharging the CRT.
Additional Procedures Battery Replacement - 7 If handled or discarded improperly, the lithium battery in the computer could explode. Review battery handling and disposal instructions in Bulletins/Safety. ±Warning: 1 2 Pull the old battery out of the battery holder. 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.
Additional Procedures Battery Replacement - 8 Note: For information about properly disposing of the old battery, refer to battery disposal instructions in Bulletins/Safety.
K Service Source Adjustments Macintosh Classic/Classic II/ Performa 200
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).
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.
Adjustments Light Meter Setup - 3 To measure a display screen’s luminance, 1 2 Set the scale switch to the bottom position (to set up the 10-50 fc scale). 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.
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: Dropping the meter can permanently damage its accuracy. A shock-damaged meter might read incorrectly or its pointer may not drop to zero.
Adjustments Light Meter Setup - 5 Lens Side Switch Model L-248 1 Read Button 2 3 Red Area Scale 4 Press the red button on the back of the light meter. If the reading is out of the red area, replace the battery. Move the side switch to its lower position so that the scale reads 2 through 10. Uncover the lens of the meter. Place the lens against the middle of the screen and press the read button to read the scale.
Adjustments Light Meter Setup - 6 Model 246 Lens Swivel Head 1 2 3 Scale 4 Remove the metal slide, if installed, from the top of the light meter. Install the white lens with the red dot. Rotate the swivel head so the lens of the meter faces the monitor. Place the lens against the middle of the screen and read the scale.
Adjustments Video - 7 Video Note: After you replace the CRT or power/sweep board, you may need to perform video adjustments. 1 Caution: Because you must make adjustments from the rear of the computer, position a mirror to view the computer screen.
Adjustments Video - 8 2 Using a small flat-blade screwdriver, depress the center tab and lift out the service door.
Adjustments Video - 9 Brightness & Contrast Contrast (PL2) Important: Readings from 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.”) Brightness (PL4) Note: Be sure the computer has been on for at least 30 minutes. 1 Run the Display Service Utility from the Utilities folder on the MacTest Pro CD.
Adjustments Video - 10 2 3 4 From the pattern selections screen, select the Full brightness screen. Hold the light meter lens against the center of the screen.
Adjustments Video - 11 • Model L-248: 10 to 11 on the 10-18 scale • Model 246: 29 on the red scale 5 Important: Over time, light meter tolerance can vary. If you doubt your meter’s accuracy, verify the readings with a known-good light meter or photometer. Press a key to return to the pattern selections screen. Select the Half brightness screen.
Adjustments Video - 12 6 Brightness (PL4) Using a plastic hex alignment tool, adjust the brightness control until the luminance at the center of the screen measures 5 foot lamberts (± 1 foot lambert), which on the light meter is • Model R77: halfway between zero and 10 on the bottom scale • Model L-248: high end of 7 on the 2-10 scale • Model 246: 5 on the red scale
Adjustments Video - 13 7 8 Press a key to return to the pattern selections screen. Select the Full brightness screen. Recheck the luminance at the center of the screen: • Model R77: 29 on the bottom scale • Model L-248: 10 to 11 on the 10-18 scale • Model: 246: 29 on the red scale If the light meter reading does not match the measurement shown, repeat the brightness & contrast procedure.
Adjustments Video - 14 Centering 1 2 3 Run the Display Service Utility. Select the Crosshatch pattern or the All-White pattern. Using the plastic hex alignment tool, adjust the horizontal centering control to center the display image horizontally within the bezel.
Adjustments Video - 15 4 Vertical Centering (PF2) Using the plastic hex alignment tool, adjust the vertical centering control to center the image vertically within the bezel.
Adjustments Video - 16 Size Adjustments 1 Horizontal Size (LL2) Vertical Size (PF1) 2 Using the plastic hex alignment tool and a ruler, adjust the horizontal size control until the display image is 7 inches (177.8 mm) wide. Using the plastic hex alignment tool, adjust the vertical size control until the display image is 4.7 inches (119.38 mm) high.
Adjustments Video - 17 Focus Adjustments 1 2 Display the Focus test pattern using Display Service Utility. Using an insulated flatblade screwdriver, adjust the focus control for the best overall focus.
Adjustments Yoke - 18 Yoke Before you begin: • Remove the cover • Discharge the CRT Warning: This product 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.
Adjustments Yoke - 19 Caution: Because you must make adjustment from the rear of the computer, position a mirror to view the computer screen. Do not reach around the computer to adjust collars and rings. Note: After you replace the CRT, you may need to adjust the yoke.
Adjustments Yoke - 20 1 Yoke Collar Yoke Clamp Screw 2 Note: If glue holds the yoke collar in place, use an art knife to cut through the glue. Loosen the yoke clamp screw two or three turns. Switch on the computer.
Adjustments Yoke - 21 3 Plastic Spokes Yoke Collar With one hand, grasp the plastic spokes of the yoke collar and rotate the yoke collar until the top and bottom edges of the picture are parallel with the top and bottom of the bezel.
Adjustments Yoke - 22 4 5 6 Yoke Collar Yoke Clamp Screw Switch off and unplug the computer. Discharge the CRT. Caution: Do not overtighten the yoke clamp screw. Hold the plastic collar in position and carefully tighten the yoke clamp screw so that the collar cannot slip.
Adjustments Yoke - 23 7 Replace the cover and switch on the computer. Make sure the top and bottom edges of the picture are parallel with the top and bottom of the bezel.
Adjustments Yoke - 24 Centering Ring Adjustment 1 2 Centering Rings Note: If glue holds the yoke collar in place, use an art knife to cut through the glue. Switch on the computer. To center the picture within the bezel: Hold the front centering ring steady and move the rear ring; then hold the rear centering ring steady and move the front ring.
K Service Source Exploded View Macintosh Classic/Classic II/ Performa 200
Exploded View 1 Exploded View 444-6104 Hard Drive 661-0216 (40 MB) Hard Drive Carrier 805-0950 462-4100 Hard Drive Data Cable (590-0211) Floppy Drive Carrier 805-5050 Floppy Drive 661-0474 Hard Drive Power Cable 590-0521 460-3400 Insulator 815-1216 Front Beze i630-5825 CRT and Yoke Assembly 076-0546 Floppy Drive Cable 590-0167 462-4100 830-0270 416-1330 Fan Power/Sweep Board 661-0597 (110V, Rev. A) 661-0599 (220V, Rev. A) 490-0001 661-0651 (110V, Rev. B) 661-0652 (220V, Rev.
