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. Apple published no schematic or component list for either drive, and the Service Source has no lens or laser adjustment.[4]
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 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).