Psion Series 3c
 | |
| A Psion Series 3c, open | |
| Specifications | |
|---|---|
| Developer | Psion PLC |
| Manufacturer | Psion PLC |
| Type | Clamshell palmtop / PDA |
| Released | 1996 |
| Discontinued | 1998 |
| CPU | NEC V30H @ 7.68 MHz, in Psion's ASIC9 |
| Memory | 1 MB ROM; 1 MB or 2 MB RAM |
| Storage | Two internal Solid State Disk (SSD) slots |
| Display | 480 × 160 monochrome LCD; backlit on later models |
| Sound | Membrane speaker, built-in microphone, 12-bit sound recording |
| Dimensions | 165 mm × 85 mm × 22 mm |
| Weight | 275 g including batteries |
| OS / Firmware | EPOC16 (SIBO), with OPL |
| Predecessor | Psion Series 3a |
| Successor | Psion Series 3mx |
| Model no. | There was never a Series 3b |
The Psion Series 3c of 1996 is a refined Series 3a: same processor, same screen resolution, but with an infrared port, a changed serial port, revised built-in software and, on later machines, a backlight. Psion never released a Series 3b.[1]
What changed from the 3a
[edit | edit source]| Change | Detail |
|---|---|
| Infrared port | Added, and visible on the case |
| Serial port | Changed — the 3c uses the same arrangement as the Siena, and a serial cable for direct connection to a Windows PC was supplied. Travel Modem connections differ between 3/3a and 3c/3mx. |
| Serial speed | Raised to 56,400 bit/s |
| Case | Redesigned: badge moved centrally on the lid, fewer undulations, matte dark grey painted finish |
| Backlight | Fitted to later models — mainly, though not only, the US 2 MB machines |
| RAM | 1 MB or 2 MB only |
| Application buttons | 9 reprogrammable buttons, against the 3a's 8 |
| Expansion | Two internal SSDs plus an external PC-Card option |
| Software | Several modifications to the built-in applications |
Everything else — the V30H at 7.68 MHz inside ASIC9, the 480 × 160 screen with its grey plane, the microphone and 12-bit sound recording, the 58-key keyboard, 2 × AA cells and the CR1620 backup cell — is as the 3a.[2][1]
For the architecture itself — ASIC9, the bank-switched memory, the hardware 32-bit RTC, the power states and the supply rails — see Psion Series 3a.
The SSD door sensing
[edit | edit source]This is the one internal difference that matters for repair.
The 3c senses the state of its SSD slot doors using a set of PCB tracks and a small metal connector on the slot door hinge. The later 3mx replaced that with a pair of angled microswitches — which is why the 3mx has a characteristic broken-switch fault that the 3c does not.[3]
On a 3c that will not see an SSD, clean the tracks and the metal door contact before suspecting anything else.
The sticky case
[edit | edit source]The 3c's redesigned case carries a rubberised soft-touch coating, and with age that coating degrades into something resembling glue. It is one of the first things a collector notices about a 3c that has been in a drawer since the 1990s.[4]
It is fixable — see Psion Series 3c General Maintenance.
Easter egg
[edit | edit source]The 3c and the later 3mx contain an Easter egg: a hidden melody and credits screen.[1]
Known problems
[edit | edit source]As with the rest of the family: hinge breakage, button bar failure, screen cable deterioration producing vertical lines,[1] and the battery lead. Add to those the sticky case coating, which is specific to the 3c.
General maintenance
[edit | edit source]Troubleshooting
[edit | edit source]Hinge repair
[edit | edit source]See also
[edit | edit source]References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 "Psion Series 3", Wikipedia. Source for the model history, the absence of a 3b, the infrared port, the changed serial port, the case redesign, the backlight, the RAM options, the Easter egg and the documented clamshell problems.
- ↑ 2.0 2.1 "Psion specifications", netogram.com. Source for the comparative specifications including serial speed, ROM and RAM sizes, keyboard button counts and backlight availability.
- ↑ Richard Zealley, "Psion Series 3mx SSD door microswitch repair", Retro Coding, 25 May 2020. Source for the difference between the 3c's door-sensing tracks and the 3mx's microswitches.
- ↑ Community discussion of the Psion 3c sticky-case problem on comp.sys.psion.misc, together with established soft-touch coating restoration practice. Source for the degradation of the 3c's rubberised finish and the isopropyl alcohol stripping method and its cautions.