PowerBook Duo 250
The PowerBook Duo 250 is a PowerBook Duo with a 33 MHz 68030 and a 9-inch active-matrix greyscale screen, introduced on 21 October 1993 with the PowerBook Duo 270c and sold until 1 May 1994. Apple's specification puts it beside the PowerBook Duo 230 in every respect except the display, the 200 MB hard drive and the higher-capacity Type II battery.[1][2] Low End Mac credits the active-matrix screen and the longer-running battery with the Duo line's rise in popularity.[3]
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| Apple's drawing of the Duo 250 logic board and display assembly (Service Source, PDF p. 209) | |
| Specifications | |
|---|---|
| Manufacturer | Apple Computer, Inc. |
| Type | Subnotebook computer |
| Released | 21 October 1993 |
| Discontinued | 1 May 1994 |
| Intro price | US$2,500 |
| CPU | Motorola 68030 at 33 MHz; FPU only in a Duo Dock |
| Memory | 4 MB on the logic board; one Duo RAM card slot, to 24 MB |
| Storage | 200 MB 2.5-inch SCSI hard drive |
| Display | 9-inch active-matrix LCD, 640 × 400, 16 grey levels |
| Sound | — |
| ROM | 1 MB |
| Power | Type II NiMH battery; 24 V DC adapter |
| Dimensions | 1.4 × 10.9 × 8.5 in (H × W × D) |
| Weight | 4.2 lb (1.9 kg) |
| OS / Firmware | System 7.1 to Mac OS 7.6.1 |
Specifications
edit| Item | PowerBook Duo 250 |
|---|---|
| Processor | Motorola 68030, 33 MHz; 68882 FPU only in a Duo Dock |
| RAM | 4 MB soldered; one Duo RAM card of 4, 6, 8, 10, 12, 16 or 20 MB, to 24 MB, 70 ns[4] |
| Display | 9-inch (229 mm) active-matrix LCD, 640 × 400, 16 shades of grey, CCFL backlight |
| Storage | 200 MB 2.5-inch SCSI hard drive |
| Main battery | NiMH Type II, 1.5 Ah, 4/5 A size cells; about 2 to 3 hours |
| Power adapter | 24 V DC, 1.04 A (25 W) |
| Gestalt ID | 38 |
Identifying a Duo 250
editApple sold a 250 upgrade kit for the 210 and 230, made up of a Duo 250 logic board and display assembly, and later a 280 kit that turned a 250 into a PowerBook Duo 280. Because of the second kit, Apple warns that the product label on the bezel does not identify a 250. The display cable does: the 210/230, 250 and 280 cables are all different, and Apple shows each one so a technician can tell them apart.[2] The 280 kit supplied a new display cable for this reason. It is slightly longer than the 250 cable, and Apple says to leave the extra length loose.[2]
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Display
editThe 250 has an active-matrix greyscale panel with a separate inverter board and brightness actuator inside the display housing.[2] Two of Apple's cautions apply only to the 250 and 280:
- The inside of the 250/280 display housing has a copper surface that flakes or peels when touched, and the flakes can short the system (PDF p. 151).[2]
- Protective tape covers the inverter board; peeling it off can short the board (PDF p. 161).[2]
Apple's rule for dead pixels on the 250 and 280: replace the display if more than five pixels stay white, or if two or more such voids are within an inch of each other (PDF p. 50).[2] Apple supplied 250 display assemblies, housings and cables to CPRC and international repairers only.[2] MacDat found no electrolytic capacitors on the 250's LCD and had not checked its inverter board.[5]
Logic board
editThe 250 shares its logic board design with the 210 and 230, and MacDat gives the same seven-capacitor list for all three.[5] Apple's exploded view lists service boards 661-1653 and 661-1672 for the 250.[2] The capacitor positions are on PowerBook Duo Capacitor Replacement Guide.
Common problems
editThe faults are those of the other 68030 Duos: leaking electrolytics on the logic board, broken screw posts in the display housing, worn-out NiMH batteries and battery contacts out of alignment.[5][2] See PowerBook Duo Troubleshooting and PowerBook Duo General Maintenance.
Documentation
editRelated pages
editReferences
edit- ↑ 1.0 1.1 Apple, "Macintosh PowerBook Duo 250: Technical Specifications" (retrieved 2026-10-02). 68030 at 33 MHz; FPU optional in dock; 25 W, 1.04 A; Duo NiMH Type II battery; 4 MB on board, one Duo RAM slot, 4-24 MB; 640 × 400 at 4 bits; introduced 10/21/1993, discontinued 5/1/1994; Gestalt ID 38; 4.2 lb; 1.4 H × 10.9 W × 8.5 D in; System 7.1 with PowerBook Duo Enabler v1.0, supported to 7.6.1; 200 MB SCSI hard drive.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 Apple Computer, PowerBook 200 Series Service Source, hosted here as File:PowerBook Duo 200 Series Service Source.pdf (see PowerBook Duo 200 Series Service Source). PDF page numbers: specifications pp. 14-28; video symptom charts pp. 40-50; display housing pp. 145-153; 210/230/250/280 display cable pp. 154-166; 250 upgrade pp. 209-211; 280/280c upgrade pp. 216-226; exploded view p. 266.
- ↑ Low End Mac, "PowerBook Duo 250" (retrieved 2026-10-02). Introduced 1993.10.21 at $2,500, discontinued 1994.05.01; improved battery lasting 2.5 hours; 4 MB to 24 MB; power supply M7783; upgrade path Duo 280. Secondary source.
- ↑ Apple Computer, Apple Memory Guide (May 2000), hosted here as File:Apple Memory Guide (May 2000).pdf (see Apple Memory Guide). PowerBook Duo 250, PDF p. 109: 4 MB soldered DRAM; cards of 4, 6, 8, 10, 12, 16 or 20 MB; 24 MB maximum; Apple supplies 4 MB and 8 MB cards.
- ↑ 5.0 5.1 5.2 MacDat, "PowerBook Duo 250 Capacitor Reference" (retrieved 2026-10-02). Same logic board list as the 210/230: one 330 µF 16 V, three 100 µF 35 V, two 100 µF 25 V (100 µF 10 V on earlier boards), one 33 µF 25 V; the 250's LCD uses no electrolytic capacitors; inverter not checked; early trackballs have one 10 µF 6.3 V. Secondary source.