RetroTechCollection

Psion Series 7 General Maintenance

Preventive maintenance for the Psion Series 7. The Psion netBook shares the case, board, screen and battery, so almost all of this applies to it too; the netBook's own page covers what differs.

The badge above the keyboard covers the only screw holding the top cover on — and is the point to press when the screen fades. This is a netBook; the Series 7 is the same machine under blue leather.

The Series 7 is a well-built machine — "the hinges are sturdy and the case is solid plastic with no small or loose parts likely to snap off"[1] — and it has aged better than most of its contemporaries. What kills them is not wear. It is the screen cable working loose in its clamp, and pulling the battery out at the wrong moment.

Three habits keep one alive: keep the machine out of vibration, never remove the main pack without watching the screen, and back up before you touch anything.

⚠️ Safety

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There are no mains voltages inside the machine. The external supply is 15.5 V at 1.5 A.[2]

The lithium-ion battery pack is the real hazard here, and it deserves the respect Battery Refurbishment describes. Do not puncture, crush or short it, and do not attempt to open it without reading Psion netBook Battery Service first.

Everything inside is CMOS. Use an anti-static strap.

Back up, always

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The internal C: drive is RAM. Several ordinary maintenance operations on this machine can empty it.

Psion's own supplied route is the desktop software, but a route that needs nothing but the machine is to copy the whole of C:, including the System directory, to a folder on a CompactFlash card, and copy it back afterwards. You have to close every application that starts at boot first, and you will have to reset the time, home city, sound and hidden-file preferences afterwards.[3]

Do this before changing either battery, before any disassembly, and before swapping a personality module.

Batteries

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Power[2][4]
Item Specification
Main Proprietary Li-ion pack, three 18650 cells, 11.1 V nominal, 1500 mAh. 8½–10 hours
Backup CR2032 lithium coin cell
External 15.5 V, 1.5 A, 100–240 V 50/60 Hz
  • Charge for the full three hours, not until the LED goes out. The charge LED extinguishes at about 70 % capacity, which is the commonest reason a healthy pack seems to be fading.[2]
  • Replace the CR2032 on a schedule. It holds your data while the main pack is out.
  • Give a stored spare pack a full charge every three months.[2]
  • Never use another Psion adapter. Nothing else in the range is 15.5 V at 1.5 A.[2]
  • Do not deep-cycle to "condition" the pack. There is no memory effect on lithium cells.[2]

Full detail, including the pack rebuild, is on Psion Series 7 Battery Service and Psion netBook Battery Service.

⚠️ Removing the main pack

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Watch the screen every time. A microswitch in the battery lock is meant to switch the machine off as you release the catch. On some machines it turns the backlight on instead, the system never shuts down, and pulling the pack wipes the internal disk.[5]

If the screen lights but stays black, hold the catch open with one hand and switch the machine off with the other before sliding the pack out.[5]

Check the battery catch periodically. One of the rubber feet sits on its underside, and sliding the machine across a desk or carrying it loose in a bag has been enough to drag the catch open and reset the machine.[5]

The screen cable

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This is the fault that ends these machines, and most of what you can do about it is preventive.

  • Keep the machine out of vibration. An owner traced repeat failures to carrying it in a rucksack pocket resting against a bicycle frame; moving it to a front pocket stopped the recurrence.[6]
  • Carry it in a case, in a padded compartment.
  • If the display starts to fade or the touchscreen drifts, act rather than living with it — the temporary fix is a firm press on the badge above the keyboard, and the durable one is a paper or cardboard shim under the cable.[6]

The full diagnosis and repair procedure is in the troubleshooting guide, including the one step that will destroy the motherboard if you rush it.

Opening the machine

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The whole machine is reached through one screw, and the route to it is a piece of tape.[6][7]

  1. Remove everything first — main pack, backup cell, the personality/ROM module and any memory expansion.[6]
  2. Warm the badge sticker with a hairdryer for about 15 seconds, covering the keyboard with paper or card first — otherwise you will lift the key legends with it. Peel it off; if it resists, warm it again.[6]
  3. Remove the single screw underneath.[6][7]
  4. With the lid half open, remove the hinge pins beside the module slots.[6]
  5. Unclip the front of the top cover and draw it forward. It carries the badge, the on/off button and the stylus button, and it takes some force.[6][7]
  6. Disconnect the keyboard at its flexible PCB connector by releasing the two locking tabs; the keyboard then lifts out as a module and unclips from slots at the front.[7]
  7. Remove the side mouldings — three screws. The right-hand moulding carries the microphone.[7]
  8. The battery sense switch lifts straight off the top left corner of the board.[7]
  9. You do not have to disconnect the LCD ribbon to lift the board — remove the two screws holding it and leave the ribbon connected. Watch the PCMCIA eject button on the right as the board comes out.[7]

The keyboard is a sealed unit and should not be disassembled further.[8]

If a keyboard has been soaked, the documented recovery is to strip it out by the route above and dry it with a dehumidifier rather than heat.[8]

Keyboard and case

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  • The legends do not fade. They are bright white transfers rather than the hot stamping or laser etching used on the Series 5 and 5mx, and this is one of the few Psions where worn lettering is not a concern.[1]
  • Clean with a barely damp cloth.
  • The leather has worn well. Contemporary assessment was that it "is very well adhered to the casing", with no coating that can peel; an owner writing eighteen years later described it as having "gained a patina".[1][9] Treat it as leather: keep it dry, keep it out of direct sun, and clean it gently.
  • One point of the leather is tightly folded when the screen is pushed fully back.[1] Not opening the lid to its absolute limit is cheap insurance for both the leather and the screen cable.
  • The rubber RS-232 port cover is poor. One long-term owner called it "lousy", though his had survived four years.[8]

Screen

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  • Run the brightness as low as you can live with. Full brightness costs roughly 50 % of runtime and "probably shortens the overall life of the screen".[1]
  • The backlight cannot be turned off — there is no function for it, even in OPL.[1]
  • The 20-second dimness at power-on is normal.[1]
  • Clean the touchscreen with a barely damp lint-free cloth. No solvents.
  • The panel is far less temperature-sensitive than the Series 5's — it "barely changes enough to bother adjusting the contrast" after time in a hot room.[1]

Storage and expansion slots

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  • Clean the CompactFlash and PC Card contacts with a foam swab and isopropyl alcohol.
  • About 6 mm of play in a Type I CompactFlash card is normal — the drawer accepts Type II devices. If a card is not reliably recognised, shim behind it with a thin piece of card, and make sure the shim cannot come loose inside.[5]
  • Reformat cards brought over from a Series 5 on the Series 7 itself. Copy the contents off, format the D: drive, copy them back. Series 5 system files can interfere with the Series 7, and applications installed from SIS files should be reinstalled rather than copied.[1]
  • Prefer CompactFlash to a Microdrive unless you need the write endurance. A Microdrive spins, draws more power and can be damaged by a drop.[1]
  • Avoid powering a serial mouse from the RS-232 port. A mouse draws its power from the port, and at least one Psion serial port was burnt out this way — the mouse worked right up to the moment it did.[3]

Resets

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Both use the reset hole under the backup battery hatch.[1]

  • Soft reset: paperclip in gently until you feel a click, then switch on without touching any keys.
  • Hard reset: with the machine on, press until the screen turns off, then hold both Shift keys while switching on. The Series 7 manual is wrong when it says a hard reset needs all batteries removed for a period.[1]

Preventive maintenance checklist

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  1. Back up C: to a CompactFlash card or a PC.
  2. Charge the main pack for a full three hours — ignore the LED.
  3. Replace the CR2032 if you do not know its age.
  4. Check the battery catch, and the rubber foot mounted on it.
  5. Press gently on the badge and watch the display. If it changes, the screen cable needs attention before it gets worse.
  6. Clean both card slots and confirm cards are recognised reliably.
  7. Inspect the leather, particularly the fold behind the hinge.
  8. Confirm the microphone still records — the contact is a press fit and known to fail.[8]
  9. Store with the machine closed, in a case, away from vibration.
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  • Cross-head and jeweller's screwdrivers, plastic spudgers, fine long-nose pliers.
  • Anti-static strap.
  • A hairdryer, for the badge sticker.
  • Isopropyl alcohol and lint-free and foam swabs.
  • A fresh CR2032 and a known-good CompactFlash card for testing.
  • A 15.5 V, 1.5 A supply with the correct barrel — 4.75 mm OD, 1.75 mm ID.[4]

See Recommended Tools for the general workshop kit, and Battery Refurbishment for the cell-work equipment.

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References

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  1. ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 "Psion Series 7 FAQ: General & hardware information", oocities.org/epoc_32 (February 2000). Source for the robustness and hinge assessment, the leather description, the screen behaviour and brightness advice, the keyboard legends, the microphone location, the CompactFlash advice, the reset procedures and the RAM figures.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 "Psion Series 7 FAQ: Power supply & charging", oocities.org/epoc_32. Source for the adapter rating and universal input, the ferrite core, the charging behaviour and 70 % LED cut-out, the runtime figures and the storage-charge advice.
  3. ↑ 3.0 3.1 OpenPsion, "Linux on the Psion netBook HOWTO — FAQs". Source for the CompactFlash backup procedure, the serial-mouse warning, the null-modem cable, the X-ray discussion and the CompactFlash size limits.
  4. ↑ 4.0 4.1 OpenPsion, "Linux on the Psion netBook HOWTO — section 3.4". Source for the pack rating and cell type, the CR2032 backup cell and the adapter connector dimensions.
  5. ↑ 5.0 5.1 5.2 5.3 "Psion Series 7 FAQ: Known issues & bugs", oocities.org/epoc_32. Source for the battery-catch microswitch fault and the rubber foot mounted on the catch, the touchscreen calibration bug and its cure in build 756, and the CompactFlash drawer play.
  6. ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 "Series 7 Repair And Supplies", PsionWiki. Source for the dismantling procedure originating with Thomas F. van der Zijden, the fragility of the white clamp, the paper-shim preventative and the vibration observation.
  7. ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 Craig Newell, "Disassembling the NetBook", 14 December 1999. Source for the disassembly sequence, the keyboard flexible-PCB connector, the side mouldings and their three screws, the microphone in the right-hand moulding, the battery sense switch and the LCD ribbon screws.
  8. ↑ 8.0 8.1 8.2 8.3 Eric Lindsay, "Psion 7 and NetBook Portable Computers", mirrored at ericlindsay.com. Source for the sealed-keyboard warning, the wet-keyboard procedure posted to comp.sys.psion by Ralph Barrett, the microphone press-fit fault, the motherboard revisions and the RS-232 port cover comment.
  9. ↑ Adam Richardson, "Psion Series 7", Mass Made Soul, 2018. Source for the long-term condition of the leather and the assessment of the hinge.


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