Tag Archives: 3a

Retro LCD screen illumination: no backlight? Try a frontlight

Leave a reply

I have written before about the Psion 5mx, a palmtop computer from the late 1990s, and I have grumbled about its LCD screen. I don’t have a problem with LCD per se — you can’t expect the same screen quality that you get with a modern colour OLED retina display — but in the right light conditions an LCD can be perfectly usable. However, the 5mx screen’s specific level of reflectivity narrows the range of lighting conditions under which it gives you a good, clear view.

Illuminating your retro tech. Image © 2025, Tony Smith (@smittytone). All rights reserved

What’s odd about this is that the 5mx’s predecessor but one, the 3a, has a really good LCD screen which provides a clear view over a wider range of lighting conditions.

Continue reading →

Psion of the times: using a 90s palmtop in the 21st Century

OK, so it was one of those purchases you can’t help yourself from making. A random, unprompted visit to eBay and suddenly I was £170 down but up one Psion Series 5mx palmtop with all the trimmings. And in very good condition it all is too.

Psion Series 5mx. Image copyright 2025 Tony Smith (@smittytone) All rights reserved

The Series 5 debuted in 1998 as the follow-up to the Series 3 family. I already have a 3a, the same model that I used for time a time back in the day. The 5 was a major upgrade: an ARM processor in place of an x86, more RAM of course, but crucially a backlit, touch-sensitive screen (plus device-dockable stylus) and a deck of larger, less calculator-like keys. In addition, out went the Series 3’s proprietary memory card format and in came a CompactFlash slot (though only one, not two as before). Psion also adopted a new serial comms port that negated the need for the Series 3’s 3Link ‘soap on a rope’ cable, which converted the 3’s proprietary bus to RS232.

Continue reading →

Ancient Palmtops as serial terminals, Part 2: the Psion 5mx and the homelab

Last year, I performed some jiggery-pokery on my headless Raspberry Pi-based HomeLab to allow my veteran Psion 3a palmtop to be used as a serial terminal for those times when SSH-ing in was not an option. The age of the 3a meant it was a sub-optimal experience, but it was usable. I recently acquired a Psion 5mx, released half a decade after the 3, and put it to the same task.

A Psion 5mx running Hermes to show a Raspberry Pi serial terminal. Image © Tony Smith (@smittytone)

The experience is much better, but I needed to tweak the PI-side settings to get results.

Continue reading →

Palmy like it’s 1999: how to revive a Psion Series 3a handheld

I have a soft spot for the technology of my younger days. In the mid-1990s, for example, I was in my late twenties and one of the machines I used for a time — all my MacWorld Boston 1994 coverage was written on one — was the Psion Series 3a. Pitched as a portable personal organiser, it was a palmtop PC running a 16-bit OS, SIBO aka EPOC 16, on an x86 CPU.

Palm computing: the Psion Series 3a

Running, I might add off a couple of AA batteries (with a coin cell to maintain RAM disk contents when the main pair were replaced) that could last for at least a month. No backlight on the monochrome LCD, though, which makes the device’s use in dim lighting tricky. Strong, over-the-shoulder lighting is essential.

Continue reading →