Atari ST Book General Maintenance

Routine care of the Atari ST Book: its battery pack and backup cells, the hinges and case, the display, the hard disk and storage. Atari's hardware specification and schematic are hosted here,^[1]^[2] and most of the practical repair experience comes from owners restoring ST Books on the exxos forum in 2024.^[3] Fault-finding is on the Atari ST Book Troubleshooting Guide and capacitors on the Atari ST Book Capacitor Replacement Guide.

Power sources

Atari specified three sources: an eight-cell NiCd pack, a seven-cell alkaline pack, and the AC adaptor/charger, which also charges the NiCd pack in the machine.^[1] atari-computermuseum.de gives the NiCd pack as 9.6 V 1300 mAh and the adaptor as a JVC PSA-4642A, 16 V 1.25 A, and says the alkaline option is seven AA cells in a special holder.^[4] The regulators accept 8 to 20 V.^[1]

NiCd pack

A full charge runs the machine for 5 to 10 hours and keeps the RAM and clock for about 100 days. The adaptor charges the pack in under two hours, using delta-V peak detection to stop without overcharging.^[1] Original packs are now old; see Battery Refurbishment for rebuilding one. A pack that is swollen, leaking or discoloured should come out of the machine.

Alkaline cells

Take the cells out before storing the machine. Alkaline residue is neutralised with white vinegar on a swab, then cleaned with isopropyl alcohol; see Battery Explosion, Capacitor or Corrosion Damage.

Internal backup cells

Rechargeable lithium cells inside the machine keep the RAM and clock running for about 40 hours when neither the pack nor the adaptor is present, for example during a pack change. They are trickle-charged from the main supply.^[1] The schematic draws the backup battery as 6.0 V on sheet 9.^[2] On a machine that has stood unpowered for years these cells are flat: one restorer found no voltage on them after about 30 years and fitted a holder for two ML2016 rechargeable cells, filing its corners to clear the neighbouring chips. With the backup cells flat, that machine needed the reset button pressed after the power button before it would start.^[3]

Switching on and off

The power button is at the lower left of the display. Hold it until the power LED turns green (supply good) or yellow (supply low). The recessed reset button is to its right, and between them is the lid switch, pressed by a pin on the case when the lid is closed.^[1] Pressing the power button while the machine is on asks the operating system to switch off; it can save the machine's state in RAM and resume it at the next switch-on.^[1]

Case and hinges

The display hinges are screwed into brass inserts set in the plastic, and the plastic around them breaks if the machine is dropped; the latch and the rear port door can also lose their pivots. On one machine the restorer:^[3]

separated the display back cover, which is held by plastic tabs, starting from either side of the lid latch with a plastic tool;
removed the twelve hinge screws (four in each hinge under the back cover and two each from the other side) and the plastic caps on each side, one of which passes the cables, and worked the hinges out;
glued cracks with thin cyanoacrylate and rebuilt the broken insert mounts with steel-reinforced epoxy, screwing cut cotton buds into the screw holes to keep the epoxy out.

Acetone, used to clean off excess glue, lifted the case paint when rubbed.^[3]

Display

The panel has no backlight, so there is no lamp or inverter to fail.^[4] Its own board carries electrolytic capacitors that leak; the symptoms are a weak picture and vertical lines, and the residue can reach the back of the glass. See the Atari ST Book Capacitor Replacement Guide.^[3] Clean the window with a soft cloth, slightly damp, and do not press on the panel.

The contrast control sets the LCD bias voltage through the MAX634 regulator at U1004.^[1]^[2]

Hard disk

The ST Book was shipped with a Conner CP2044 2.5-inch IDE drive of 42.6 MB.^[4] It uses IDE in AT mode, not ACSI.^[1] On the machines restored on the exxos forum the original drives had failed, one with its seal material leaking into the drive bracket. A CompactFlash card on a 2.5-inch IDE adaptor works as a replacement, partitioned with BOOKFMT.PRG from the ROM disk, drive P:; a 512 MB card worked where a 4 GB card did not. The factory TOS will not boot without a working partitioned disk or a floppy drive and shows four bombs instead.^[3] Back up the original drive first if it still runs. See Hard Drive Maintenance and Repair.

Keyboard

The keyboard and Vector Pad are scanned by a COP888CG controller (U703 on sheet 8).^[2] Blow debris out with compressed air with the power off. One restorer connected a Mega ST keyboard through an adapter, which is a way to tell a keyboard fault from a machine fault.^[3]

Storage

Remove alkaline cells. A charged NiCd pack keeps the RAM and clock for about 100 days, after which the internal backup cells last about 40 hours.^[1]
Keep the adaptor and any cables with the machine; only the transfer cable among Atari's planned ST Book accessories was ever released.^[4]
Cool and dry, out of direct sunlight, with nothing on the lid.

Related pages

References

↑ ^1.00 ^1.01 ^1.02 ^1.03 ^1.04 ^1.05 ^1.06 ^1.07 ^1.08 ^1.09 Atari Corporation, ATARI STBook Hardware Specification, 10 September 1992: section 2.3 (IDE interface) and section 10 (power supply: sources, batteries, backup cells, switches and controls, pp. 28–35). Hosted here: File:Atari STBook Hardware Specification.pdf.
↑ ^2.0 ^2.1 ^2.2 ^2.3 Atari Corporation, Schematic Diagram MAXIST, drawing C104446-001 Rev 7.0: sheet 8 (keyboard controller U703) and sheet 9 (power system, MAX634 U1004, backup battery). Hosted here: File:Atari STBook Schematic Rev 7.0 C104446-001.pdf.
↑ ^3.0 ^3.1 ^3.2 ^3.3 ^3.4 ^3.5 ^3.6 Thread "Repairing a ST Book.", exxos forum, posts by AndresPlazaR, 12 July to 21 September 2024, https://www.exxosforum.co.uk/forum/viewtopic.php?t=7118 (pages 1 to 4, retrieved 2026-10-01).
↑ ^4.0 ^4.1 ^4.2 ^4.3 "Leichtgewicht: Das ST BOOK", atari-computermuseum.de, last edited 25 August 2024, https://www.atari-computermuseum.de/nst.htm (retrieved 2026-10-01).

[spec-1] 1.00 ^1.01 ^1.02 ^1.03 ^1.04 ^1.05 ^1.06 ^1.07 ^1.08 ^1.09 Atari Corporation, ATARI STBook Hardware Specification, 10 September 1992: section 2.3 (IDE interface) and section 10 (power supply: sources, batteries, backup cells, switches and controls, pp. 28–35). Hosted here: File:Atari STBook Hardware Specification.pdf.

[sch-2] 2.0 ^2.1 ^2.2 ^2.3 Atari Corporation, Schematic Diagram MAXIST, drawing C104446-001 Rev 7.0: sheet 8 (keyboard controller U703) and sheet 9 (power system, MAX634 U1004, backup battery). Hosted here: File:Atari STBook Schematic Rev 7.0 C104446-001.pdf.

[exxos-3] 3.0 ^3.1 ^3.2 ^3.3 ^3.4 ^3.5 ^3.6 Thread "Repairing a ST Book.", exxos forum, posts by AndresPlazaR, 12 July to 21 September 2024, https://www.exxosforum.co.uk/forum/viewtopic.php?t=7118 (pages 1 to 4, retrieved 2026-10-01).

[acm-nst-4] 4.0 ^4.1 ^4.2 ^4.3 "Leichtgewicht: Das ST BOOK", atari-computermuseum.de, last edited 25 August 2024, https://www.atari-computermuseum.de/nst.htm (retrieved 2026-10-01).

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