As a portable device that runs off 4 AA cells, it's quite interesting for several reasons.
- It contains a version of BBC basic, and you can write programs, with a few caveats, that will run on the original BBC machines. This is accessed by pressing Function+B and programs may be saved.
- It has a built in serial terminal. This is accessed by pressing Function+S.
- It is actually 8 bit as it runs a low power version of the Z80 CPU from the ZX80/81/Spectrum et al.
- Expanded to 1MB via PCMCIA cards, it will even run CP/M.
First off was the keyboard, which had some sticky keys, and that was quickly resolved by dismantling it and cleaning the key stems with soap and water.
Luckily, there is some useful documentation out there for this little machine, so I set out looking for possible causes, and it seems there is a small SMD fuse, .8a, in the positive power rail which commonly fails, so I took that as my first port of call.
Then I hit my next problem. Being in a rental property temporarily I had managed to pack all of my tools away into storage, so not even a multi-meter to start investigating.
So I had to hit up Amazon Prime, and the next day had a cheap multi-meter and soldering iron all for under £20, which shows how easy it is to get started.
Multi-meter in hand I quickly diagnosed that the fuse had indeed blown, and since it is in line with both the batteries and the power adaptor socket, it had to be fixed before going any further.
Here's the back of the mainboard, where the fuse can be found:
And the fuse, marked F301, is up on the left hand side near the backup battery location, removed in the following picture:
As I had no spare fuse, I had to fit an @exxos approved bodge wire:
Batteries in, I hooked up the display and got this:
So I grabbed a CR2032, held it in place and powered on again:
A quick bout of reassembly later, I powered on, set the Y2K compliant clock and got this:
Very happy to have this interesting, compact little machine up and running.