AppleCD SC
| AppleCD SC | |
|---|---|
 |
|
| AppleCD SC (All About Apple museum, CC BY-SA 3.0) | |
| Manufacturer | Apple Computer, Inc. |
| Type | External SCSI CD-ROM drive |
| Release date | 1988 (AppleCD SC); 1991 (AppleCD SC Plus) |
| Price | US$1,199 (1988) |
| Interface | SCSI, two 50-pin ports |
| Compatible | Macintosh with a DB-25 SCSI port; Apple II Plus, Apple IIe and Apple IIGS with an Apple II SCSI card |
| Dimensions | 8.4 × 24.6 × 26.6 cm (3.31 × 9.69 × 10.47 in) |
| Weight | 4 kg (8.8 lb) |
| Model | M2700/A (SC); M2700LL/C (SC Plus) |
| Power | 85-270 V AC, 47-64 Hz, 40 W (SC); 100-240 V AC, 50-60 Hz, 40 W (SC Plus) |
| Storage | 656 MB (Mode 1), 748 MB (Mode 2) per disc |
| Media | 12 cm CD-ROM or audio CD in a CD caddy |
The AppleCD SC is Apple's first CD-ROM drive, an external caddy-loading SCSI drive for the Macintosh and the Apple II, introduced in 1988.[1] It reads CD-ROM data at 150K/s (Mode 1) and plays audio CDs through a front headphone jack and two RCA jacks on the back.[2] The AppleCD SC Plus of 1991 uses the same case with a faster drive mechanism and adds ISO 9660 support.[3][4]
History
[edit | edit source]Apple's service-launch presentation for the drive gives the announcement as the Microsoft CD-ROM conference in March 1988, a ship date of 2 May 1988 and a price of $1,199. The same slides list the formats the drive could read at launch: CD audio, ProDOS, HFS and High Sierra.[5] In September 1988 Apple added ISO 9660/High Sierra software for the Macintosh and Apple IIGS and an Apple CD-ROM Explorer disc to the accessory kit. Existing owners could get the new software free with a coupon from the early kits, or from AppleLink, until the end of 1988.[6]
The AppleCD SC Plus, order number M2700LL/C, appeared in Apple's June 1991 data sheet.[3] Early AppleCD SC drives have a cooling fan. The SC Plus has none, and Apple's service instruction for the SC is to disconnect the fan and leave it disconnected, because it draws dust onto the lens.[4] An Apple Tech Info Library article titled "AppleCD SC: Fan Deleted in 1990" dates the change in production.[1]
Specifications
[edit | edit source]| Item | AppleCD SC | AppleCD SC Plus |
|---|---|---|
| Average access time (including latency) | 500 ms typical (under 600 ms) | 380 ms typical |
| Maximum access (first to last block) | 800 ms typical (under 1.2 s) | 650 ms typical |
| Data-streaming rate | Mode 1 150K/s; Mode 2 171K/s; 75 blocks/s | |
| SCSI transfer rate | About 800K/s | 1.5 MB/s burst |
| Buffer | 64K RAM | |
| Rotational speed | About 230-530 rpm (variable) | |
| Startup / spin-down | 5 s typical (media-dependent) / 2 s typical | |
| Capacity | Mode 1 656 MB, 2,048 bytes per block; Mode 2 748 MB, 2,336 bytes per block; more than 270,000 blocks | |
| File systems | HFS, ProDOS, High Sierra; ISO 9660 from September 1988 | HFS, ProDOS, High Sierra, ISO 9660 |
| Line voltage | 85-270 V AC, 47-64 Hz | 100-240 V AC, 50-60 Hz |
| Maximum power | 40 W | |
| Operating environment | 10-40 °C; 10-90% RH non-condensing; −1,000 to 15,000 ft | |
The SC Plus owner's guide adds a track pitch of 1.6 microns, a scanning velocity of 1.2-1.4 m/s, an average latency of 55-130 ms and a noise level below 46 dB with the drive on.[7]
Controls and connections
[edit | edit source]
The front panel has the caddy slot, a power-on light, an in-use light, an eject button for Apple II use, the headphone jack and a volume control. The back has two SCSI ports, two audio jacks, the SCSI ID number with the ID switch below it, the power socket and the power switch.[7]
The factory SCSI ID is 3. To change it, switch the drive off and press the point of a pushpin or a straightened paper clip into the hole below the ID number until the number you want appears. Apple's external SCSI devices have no built-in terminator, so a drive at the end of the chain needs an Apple SCSI Cable Terminator.[7]
A Macintosh connects through its DB-25 SCSI port. The AppleCD SC works with an Apple II Plus, IIe or IIGS fitted with the Apple II SCSI Interface Card with Rev. C or later ROMs (A2B2087).[2] The SC Plus data sheet lists the Apple IIe and IIGS, and the Apple II High Speed SCSI Card (A0220LL/A) as a related product.[3] To start up a IIGS from the SC Plus, Apple specifies GS/OS 5.0.4 and at least 1 MB of RAM.[7]
Inside the drive
[edit | edit source]Apple's owner's guide describes the SC Plus as a disc drive mechanism with an optical read head, servo electronics for focus, tracking and spindle speed, decoding and error-correction logic, a system controller, a SCSI controller with a 64K buffer, an audio DAC and amplifier, and the power supply assembly.[7] Apple serviced the drive at module level. The Service Source exploded view names the case top, fan (SC only), SCSI select switch, rear audio board, SCSI-device-to-case cable, connector mounting plate, headphone board, LED board, CD-ROM drive and power supply.[4]
The mechanisms are Sony units. Herb Johnson's Retrotechnology lists a Sony CDU-8001 in the AppleCD SC and a CDU-8002 in the SC Plus.[8] A 68kMLA member who opened an AppleCD SC in 2017 found a CDU-8001; another member noted that the SC and SC Plus mechanisms are not the standard half-height 5.25-inch size of later drives.[9]
AppleCD SC Plus
[edit | edit source]The SC Plus keeps the SC's case, size, weight, caddy and connections.[4] Apple's figures give it a shorter access time (380 ms against 500 ms typical), a faster SCSI burst rate (1.5 MB/s against about 800K/s), a narrower mains input range (100-240 V against 85-270 V) and no fan.[3][4] Its data sheet adds ISO 9660 to the file systems and drops the Apple II Plus from the list of Apple II hosts.[3]
Maintenance and repair
[edit | edit source]The AppleCD SC General Maintenance page covers cleaning, the fan, caddies and Apple's take-apart sequence. The AppleCD SC Troubleshooting Guide collects Apple's symptom charts and the owner's guide troubleshooting appendix. Neither the Service Source nor the SC Plus owner's guide has a schematic or component list, and the Service Source has no lens or laser adjustment.[4][7]
Documentation
[edit | edit source]- AppleCD SC/SC Plus Service Source: Apple's module-level service manual for both drives.
- AppleCD SC Documentation: the 1989 and 1991 data sheets, the 1991 SC Plus owner's guide and the 1988 enhancements note.
Related pages
[edit | edit source]- AppleCD SC General Maintenance
- AppleCD SC Troubleshooting Guide
- AppleCD 150
- Hard Drive Maintenance and Repair
References
[edit | edit source]- ↑ 1.0 1.1 "AppleCD", Wikipedia, en.wikipedia.org/wiki/AppleCD (retrieved 4 October 2026). AppleCD SC as Apple's first CD-ROM drive (1988); AppleCD SC Plus as its 1991 replacement; cites Apple Tech Info Library article TA46253, "AppleCD SC: Fan Deleted in 1990".
- ↑ 2.0 2.1 2.2 Apple Computer, AppleCD SC data sheet, A7F0081/A, April 1989, hosted as File:AppleCD SC Data Sheet (1989).pdf. p. 2 features (front-loading slot, 64K RAM buffer, High Sierra, AppleShare support, CD caddy, universal power supply, CD Remote, two RCA jacks, headphone jack); p. 3 system requirements and technical specifications; p. 4 ordering information, order number M2700/A.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Apple Computer, AppleCD SC Plus data sheet, A7F0081/B, June 1991, hosted as File:AppleCD SC Plus Data Sheet (1991).pdf. p. 1 High Sierra and ISO 9660; p. 3 system requirements and technical specifications; p. 4 order number M2700LL/C, related products.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Apple Computer, AppleCD SC/SC Plus Service Source, hosted as File:Applecd sc-sc plus.pdf (see AppleCD SC/SC Plus Service Source). Specifications pp. 1-7 (PDF pp. 3-9); Troubleshooting pp. 1-4 (PDF pp. 11-14); Take Apart (PDF pp. 16-44); Additional Procedures, Disable Fan (PDF pp. 46-47); Exploded View (PDF p. 49).
- ↑ Apple Computer, AppleCD SC: Service Product Support (presentation slides, 1988, 16 pp.), in the archive.org item apple-cd-sc-reference-alpha-draft-1988 (AppleCD SC Complete Package, Brutal Deluxe). Slides "AppleCD SC Schedule" (announcement, ship date, price), "Supported Formats", "Features" (500 ms access, 64K RAM buffer) and "Repair Strategy".
- ↑ Apple Computer, "AppleCD SC Enhancements" (dealer note, 1988), hosted as File:AppleCD SC Enhancements (1988).pdf.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 Apple Computer, AppleCD SC Plus Owner's Guide (1991), hosted as File:AppleCD SC Plus Owner's Guide (1991).pdf. Care and handling pp. 6-7 (PDF pp. 18-19); SCSI terminators p. 11 (PDF p. 22); SCSI ID p. 12 (PDF p. 23); Figure 1-2 p. 4 (PDF p. 16); Apple II requirements p. 5 (PDF p. 17); Appendix A Troubleshooting pp. 81-87 (PDF pp. 90-96); Appendix B pp. 92-95 (PDF pp. 101-104); Appendix C Specifications pp. 96-98 (PDF pp. 105-107).
- ↑ Herb Johnson, "Mac Hard and CD-ROM Drives, Technical info", Retrotechnology, retrotechnology.com/herbs_stuff/m_scsi.html (retrieved 4 October 2026). Drive mechanisms in Apple's external CD-ROM cases.
- ↑ "Apple CD SC - Not reading disks properly??", 68kMLA forum thread, January 2017, 68kmla.org. Posts by BadGoldEagle (CDU-8001; constant ejecting cured by cleaning the lens; radial electrolytics in the SC), CelGen (non-standard mechanism size; leaking surface-mount electrolytics in early-1990s Sony drives) and techknight (normal idle servo noise; the drive waits for SCSI commands).