The Microtan 65 was basic but expandable way beyond other ’80s home computers. Mike Bedford explains how to experience it via emulation.

Although the Sinclair ZX80 is commonly thought of as the machine that kickstarted the ’80s home computer boom in the UK, an earlier machine may have also played a part, as we saw two issues ago. The Science of Cambridge MK14 (see LXF314) came three years earlier, was cheaper, and sold in significant numbers. But even the MK14 wasn’t alone in these pre-ZX80 days, which brings us to our subject here.

In 1979, a now barely remembered company called Tangerine Computer Systems introduced the Microtan 65 home computer. As we’ll see, it has similarities to both the earlier MK14 and the soon-to-be-released ZX80. And the good news is that you can get to grips with it through emulation.

Spotlight on Microtan

The Microtan 65 was similar to the MK14 in that it was supplied as just a single board with no power supply or case. Also like the MK14, it was expandable by the addition of expansion boards. As we’ll see later, though, it was very much more expandable than the MK14, and this was one of its main selling points to the more serious enthusiast.

This system contains just a Microtan 65 and a TANEX card, but the full-sized motherboard means it would have been well placed for future expansion.

CREDIT: Ian Dunster

Turning to the ZX80, the Microtan was also similar to this machine in having a video display, rather than the MK14’s onboard LEDs. And unlike the MK14, which was only available as a kit, the Microtan was, like the ZX80, available either as a kit or ready built. The price of the two computers weren’t too dissimilar either, the Microtan 65 costing £79.93 in kit form.

In other ways, though, the Microtan 65 was quite different from the pioneering MK14 and the ZX80. For a start, the processor was neither the somewhat unusual SC/MP found in the MK14, nor the Zilog Z80 used in the ZX80. However, the Tangerine machine did go the same way as several of the ZX80’s successors in using the 6502 processor. In many other respects, though, the Microtan 65 followed a very different path from virtually all the home computers of the early ’80s. The MK14 had an onboard hex keypad while nearly all the later home computers had QWERTY keyboards. The Microtan 65 had neither as standard, and this is one of the first examples of its expandable nature and the choices this provided. So, a keypad was available, as was a full keyboard, the latter being extraordinarily expensive in the late ’70s, so many users started with the keypad and later upgraded to a keyboard. In fact, with just the basic Microtan 65 board, the hex keypad was entirely adequate since it didn’t have Basic, so programming was via machine code.