The awakening of the Spectrum 128K

In 1985, the 128K version of the Sinclair ZX Spectrum was designed and sold first in Spain by Investrónica S.A. Investrónica was the official dealer for Sinclair products in Spain until Amstrad bought the rights on the 80s successful computer. Investrónica was also part of the El Corte Inglés group, a big Spanish corporation, whose most known company was (and is) “El Corte Inglés” department stores.

Image for post
Image for post
A boxed Spanish Spectrum 128K

Investrónica was as technology company with a wide experience in building electronic machines, the core of their business was creating an providing expensive machines for tailoring companies, but they also were investing in many areas, and consumer electronics was one of them.

According Jose Antonio Landrove, Chief Procurement Officer at Investronica in 1985, early that year Sinclair was not interested in developing the Spectrum further than the 48K+, as their efforts were concentrated in the QL and the C5.

Investrónica had already a large experience in building electronics, and also had permission from Sinclair to create their own keyboards. Spanish regulation forced all computers sold in Spain to have spanish special characters in their keyboard, so they were already purchasing 48K+ cases to swedish company Celluloid AB (also a provider of Sinclair Research), and membranes to a british company located in the Isle of Wight named NFI. The 48K boards were of course bought to Sinclair and then all pieces were properly assembled in Spain.

As Sinclair was not interested in building a 128K Spectrum, but Investrónica foresaw some good income from such a model, they asked Sinclair for permission to design a 128K Spectrum themselves, and Sinclair agreed. The project was internally nicknamed “Derby”.

So basically Investrónica had already a provider for cases and membranes, and just required to design the board. It happened that by that time Martin Brennan, John Mathieson and Ben Cheese, all of them Sinclair Research ex-employees , have founded their own company, Flare Technology, and they knew a lot about the ZX Spectrum, so the motherboard design was
comissioned to them, with the exception of the 128K ULA, whose design was made by Texas Instruments.

There was another provider involved: the Chilean industrial designer Guillermo Capdevila updated Rick Dickinson’s case design, and it’s because of him that the 128k+ model is today nicknamed “the toastrack”, as he was the one adding that quite visible feature. He was most likely also the designer of the numeric keyboard that was bundled together with Spanish 128K+, although for obvious reasons the design was strongly based on the original case design made by Dickinson.

Once the board and case designs were made, the boards were built in Madrid by Spanish company Sagitron, a company already working for Investrónica for many other electronic projects. Contracting Sagitron instead of Timex was a reasonable option, as they were reliable and at that time, when Spain was not yet in the EU, using Timex as provider would have meant adding some import taxes.

Image for post
Image for post
Contents of the Spanish 128K Spectrum box

The Spectrum 128K was marketed in 1985 in Spain, ready for the Christmas campaign, and not until 1986 in UK. Apparently Sinclair had too much stock of 48K boards to sell and that forced them to delay launch in UK, although that may be just a rumour, as maybe it’s because by Christmas Sinclair was already having financial problems due to the big failure with the C5, and their debt with Timex made asking for new boards impossible.

So in the end, Investrónica pushed so a 128K version existed, and took the leading place as Sinclair was not interested (or just unable) to do it. Should Investrónica took another path, there may had not been a 128K Spectrum, and maybe Amstrad would also had had less interest in the deal that less than one year later (April, 1986), as the 48K designs were clearly outdated in 1986 when compared with other competitors in the market.

Image for post
Image for post
The Spanish ROM in the 128K board, with the project nickname “Derby” on it (on a sticker)

The knowledge adquired by Investrónica while building the 128K Spectrum lead a few months later to the design of the Inves Spectrum, probably one of the first, or maybe the first, western Europe clones of the Spectrum 48k. Investrónica was replaced by Indescomp, another Spanish company, as official Sinclair dealer once Amstrad bought the rights on the Sinclair computers, so they designed their own clone, an action that ended in a trial when Amstrad sued Investrónica because of that, but well, that’s another story.

So what’s different in the Spanish 128K Spectrum models?

The English engineers who received the original design made some changes to the 128K board and ROM, so there are changes between both versions.

  • As it already happened with first issues of 48K boards, the Spanish boards had bugs: the most important one is the CLK signal of Z80 CPU is not routed to the edge connector, so some devices that require that signal, doesn’t work or doesn’t work well (i,.e. DivMMC). It’s easly fixable by just soldering a wire to the proper edge pin anyway.
Image for post
Image for post
Spanish keyboard
  • The ROM was also updated so all messages are in Spanish. The basic tokens were not translated (what would had been a very bad idea anyway).
Image for post
Image for post
Spanish error message for “D BREAK — CONT repeats”
  • The computer starts with a copyright notice “©1985 Sinclair Research LTD ESPAÑOL” instead of using the usual start menus you can see in the English one, and in the Amstrad models. It’s a message closer to the original 48K models “© 1982 Sinclair Research Ltd”.
Image for post
Image for post
Copyright message
  • Updated charset in the ROM so it supports Spanish characters (¿,¡,Ñ, Ü)
Image for post
Image for post
Spanish charset
  • The Spanish version includes a full screen text editor, that you could call by using the new token EDIT (i.e. EDIT E$). That was a built-in competitor for Tassword and other word processors at the time, but being limited to 32 columns made it only usable with zx printer, so it was not very successful. Still, it has a lot of features that could be invoked by using the numeric keyboard, that made it quite good (but for the 32 columns issue).
Image for post
Image for post
The Spanish 128K word processor
  • The BASIC editor was improved, but engineers at Sinclairs restore the original one in English version. It had a full screen editor (instead of line by line), and the alignment when the code was listed was better than previous and later versions.
Image for post
Image for post
Full screen editor
Image for post
Image for post
List of basic code (Naulen, by Mariano Chiaverano)
  • Additional tokens. Apart of EDIT, there were two more: RENUM (which allowed renumbering code, which properly updated GOTO and GOSUB calls) and DELETE (allowing deleting a range of basic lines). The Spanish version of RENUM allowed selecting start line, new number for that line, and step between lines. The English version had no parameters and automatically renumbered all lines in steps of 10. DELETE was removed from the English versions. Of course, basic instructions PLAY and SPECTRUM, were implemented first in this version, but those ones remained in the english one.
Image for post
Image for post
The Calculator

In the end, the Spectrum 128K become the most compatible with previous software from all 128K Spectrums, probably cause people at Flare and Texas Instruments did know what we were doing very well. The first Amstrad model kept same compatibility cause the chief engineer at Amstrad was given a 128K Spectrum and asked to clone that before Christmas campaign started, so not many changes were done.

Later models, the black models (+2A/B and +3) were less compatible cause they were rebuilt by Amstrad engineers on their own.

Disclaimer

This article is based on what is possible to check today, and what has been told by Jose Luis Landrove from Investrónica, if you have further or different information please don’t hesitate to let me know, so the article can be completed, or different point of views shown.

Greetings

For writing this article I have used the following sources, apart of my own experience:

Note: I’ve also used several photographs from the 128K model and box taken from the internet. I could have made myself most of those photographs as I own a Spanish 128K Spectrum, but I didn’t consider losing time doing them with so many photographs available. It’s difficult to list authors here but if you recognize some photograph of yours and want to be acknowledged please let me know. If you want me to remove your photograph please let me know as well.

Written by

Developing indie interactive fiction and IF engines since 1984

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store