Josh: New page: Duo 230, specs from Apple SS and SP155, board capacitors, display, upgrades

2026-10-02T08:37:11Z

New page: Duo 230, specs from Apple SS and SP155, board capacitors, display, upgrades

New page

{{Infobox computer
| name = PowerBook Duo 230
| image = [[File:PowerBook Duo 230 (All About Apple museum).jpg|260px|frameless]]
| caption = PowerBook Duo 230 (All About Apple museum, Wikimedia Commons, CC BY-SA 3.0)
| manufacturer = Apple Computer, Inc.
| type = Subnotebook computer
| release_date = 19 October 1992
| discontinued = 18 July 1994
| price = US$2,610
| 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
| rom = 1 MB
| storage = 80 or 120 MB 2.5-inch SCSI hard drive
| display = 9-inch FSTN passive-matrix LCD, 640 × 400, 16 grey levels
| power = Type I 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 = System 7.1 to Mac OS 7.6.1
}}
The '''PowerBook Duo 230''' is the 33 MHz model of the first pair of PowerBook Duos, introduced with the [[PowerBook Duo 210]] on 19 October 1992. Apart from the faster 68030 and the larger hard drive options, the two are the same machine: a 4.2 lb subnotebook with a 9-inch passive-matrix screen, a trackball, one serial port and a 152-pin docking connector.<ref name="sp155">Apple, [https://support.apple.com/kb/SP155 "Macintosh PowerBook Duo 230: Technical Specifications"] (retrieved 2026-10-02). 68030 at 33 MHz; FPU optional in dock; printer port only; 25 W, 1.04 A, 100-240 V; Duo NiMH Type I battery; 4 MB on board, one Duo RAM slot, 4-24 MB; 640 × 400 at 4 bits; introduced 10/19/1992, discontinued 7/18/1994; Gestalt ID 32; 4.2 lb; 1.4 H × 10.9 W × 8.5 D in; System 7.1 with System Enabler 201, supported to 7.6.1; 80-160 MB SCSI hard drive.</ref><ref name="ss">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; symptom charts pp. 32-73; take apart pp. 75-196; upgrades pp. 209-239; battery procedures pp. 241-264; exploded view p. 266.</ref> The 230 outlived the 210: Apple kept selling it alongside the [[PowerBook Duo 250]] and [[PowerBook Duo 270c]] until July 1994.<ref name="sp155" />

== Specifications ==
<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:70%;"
|+ '''Apple's specifications'''<ref name="ss" /><ref name="sp155" />
! Item !! PowerBook Duo 230
|-
| Processor || Motorola 68030, 33 MHz; no FPU in the computer (a 68882 can be fitted in a Duo Dock)
|-
| RAM || 4 MB soldered; one Duo RAM card of 4, 8, 16 or 20 MB, to 24 MB, 70 ns or faster<ref name="amg">Apple Computer, ''Apple Memory Guide'' (May 2000), hosted here as [[:File:Apple Memory Guide (May 2000).pdf]] (see [[Apple Memory Guide]]). PowerBook Duo 210/230, PDF p. 108: 4 MB soldered DRAM; cards of 4, 8, 16 or 20 MB; 24 MB maximum; Apple supplies 4 MB and 8 MB cards, other sizes from third parties.</ref>
|-
| ROM || 1 MB (ROM ID $067C)
|-
| Display || 9-inch FSTN passive-matrix LCD, 640 × 400, up to 4 bits per pixel (16 grey levels), CCFL backlight
|-
| Storage || Internal 2.5-inch SCSI hard drive, 17 mm high; 80 or 120 MB fitted<ref name="wp">Wikipedia, [https://en.wikipedia.org/wiki/PowerBook_Duo "PowerBook Duo"] (retrieved 2026-10-02). Duo 230 with an 80 MB or 120 MB drive, at US$2,609; Duo 210 at US$2,249. Used for history only.</ref>
|-
| Ports || RS-422 serial (mini DIN-8); 152-pin docking connector; Express Modem slot
|-
| Main battery || NiMH Type I, 0.95 Ah
|-
| Power adapter || 24 V DC, 1.04 A
|-
| Gestalt ID || 32
|}

Apple's specification page lists drive sizes from 80 to 160 MB for the 230.<ref name="sp155" /> Low End Mac gives the launch price as US$2,610 and the introduction as 22 October 1992; Apple's page gives 19 October.<ref name="lem230">Low End Mac, [https://lowendmac.com/1992/powerbook-duo-230/ "PowerBook Duo 230"] (retrieved 2026-10-02). Introduced 1992.10.22 at $2,610, discontinued 1994.07.18; 4 MB to 24 MB; power supply M7783; upgrade path Duo 280. Secondary source.</ref><ref name="sp155" />

== Hardware ==
=== Logic board ===
The 230 uses the same logic board as the 210 and 250. Fizzbinn's board was silkscreened 820-0426-D and carried seven surface-mount electrolytics: C2 and C11 (100 µF 25 V), C3, C5 and C9 (100 µF 35 V), C14 (330 µF 16 V) and C36 (33 µF 25 V).<ref name="fizz">68kMLA forum thread [https://68kmla.org/bb/threads/powerbook-duo-230-repair-and-preventive-maintenance.38464/ "PowerBook Duo 230 repair and preventive maintenance"], Fizzbinn (May 2021, reposted July 2021) and chartreuse (August 2021). Logic board 820-0426-D: C2, C11 100 µF 25 V; C3, C5, C9 100 µF 35 V; C14 330 µF 16 V (chartreuse lists the 330 µF part as C8); C36 33 µF 25 V; Sharp LM64N794 panel with C1-C8 3.3 µF 35 V; leaking C36 and panel capacitors; damaged via at C35; hinge stand-off repair; keyboard contact cleaning with a white eraser. Community repair report.</ref> A second owner, chartreuse, found only the LCD capacitors and C36 leaking on that board; the via for C35 was damaged and had to be bridged with a wire.<ref name="fizz" /> Apple's service boards for this model were 661-1653 and 661-1672.<ref name="ss" />

=== Display ===
The passive-matrix panel in Fizzbinn's 230 was a Sharp LM64N794 with eight 3.3 µF 35 V capacitors, C1 to C8. Two had started to leak. Replacing them reduced the banding on the screen.<ref name="fizz" /> Apple treats a thin white line across the middle of an FSTN screen, uneven brightness and colour fringes at steep angles as normal.<ref name="ss" />

=== Case and keyboard ===
The plastic posts that hold the brass screw inserts behind the display bezel break away with age. Fizzbinn cut back the broken plastic and set the inserts in JB Weld PlasticWeld epoxy.<ref name="fizz" /> The keyboard comes apart once the keycaps are pulled, and chartreuse restored unreliable keys by rubbing the membrane contacts with a white eraser after contact cleaner and DeoxIT made no difference.<ref name="fizz" /> Apple's own warning is that overtightened keyboard screws warp the keyboard and jam the space bar.<ref name="ss" />

== Upgrades ==
Apple sold kits that turned a 230 into a [[PowerBook Duo 250|250]], a [[PowerBook Duo 270c|270c]] or a [[PowerBook Duo 2300|2300c]]. The 2300 kit replaces the case bottom, logic board and CPU stiffener, and on a 210, 230 or 250 the old FSTN display cable goes to the 2300c board's FSTN connector (J6).<ref name="ss" /> One 68kMLA member bought a boxed 230 with "PowerBook 2300" on its base, which ran Mac OS 8.1 in 16 greys on the original passive-matrix screen.<ref name="upg">68kMLA forum thread [https://68kmla.org/bb/threads/powerbook-duo-230-upgraded-to-2300.26844/ "Powerbook Duo 230 upgraded to 2300"], FlyingToaster, Mk.558 and others, December 2012. A Duo 230 with a 2300 base, 16 greys at 640 × 400, an IDE to CompactFlash adapter. Community report.</ref>

== Common problems ==
Opinions on capacitor leakage in the Duo differ. MacDat says every 230 must be recapped because leaking electrolyte can short and destroy the logic board; on 68kMLA in 2019 Byrd judged the Duos the most reliable 68k PowerBooks, with little leakage in his experience.<ref name="macdat230">MacDat, [https://macdat.net/cap_reference/apple/powerbook/duo230.html "PowerBook Duo 230 Capacitor Reference"] (retrieved 2026-10-02). Logic board: 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; LCD: eight 3.3 µF 35 V; early trackballs: one 10 µF 6.3 V; do not use ceramic capacitors on the LCD. Secondary source.</ref><ref name="adv">68kMLA forum thread [https://68kmla.org/bb/threads/powerbook-duo-230-advice.34381/ "Powerbook Duo 230 Advice"], October-November 2019. Byrd and Papichulo on Duo reliability and capacitor leakage. Community opinion.</ref> Both reports above found leaking parts on 230s.<ref name="fizz" /> See:
* [[PowerBook Duo Capacitor Replacement Guide]]
* [[PowerBook Duo Troubleshooting]]
* [[PowerBook Duo General Maintenance]]

== Documentation ==
* [[PowerBook Duo 200 Series Service Source]]
* [[Apple Memory Guide]] (PDF p. 108)<ref name="amg" />

== Related pages ==
* [[PowerBook Duo 210]], [[PowerBook Duo 250]], [[PowerBook Duo 270c]], [[PowerBook Duo 280]], [[PowerBook Duo 2300]]

== References ==
<references />

{{Navbox-AppleVintage|state=collapsed}}

[[Category:Apple Vintage Computers]]

PowerBook Duo 230 - Revision history

Josh: New page: Duo 230, specs from Apple SS and SP155, board capacitors, display, upgrades