Sinclair Spectrum Vega Plus Console

The Timex TS 1000 and its clones (yeah, clone of a clone, wondering if its electronics DNA was faithfully copied) were basically a ZX81, the only noticeable difference was the amount of RAM, 2Kb (TS1000 and CZ1000) instead of 1Kb!. Both the Timex and the Czerweny have the same ULA the ZX81 carried, same power supply but the modulator was "tuned" for NTSC instead of PAL so the Xtal was also for NTSC standard (about 3.57Mhz instead of 3.58Mhz of PAL systems). While Timex sold the official ZX81 clone, renamed TS1000, Microdigital of Brasil and Czerweny of Argentina (mostly an induction motors manufacturer) produced the TK83 and the CZ1000, respectively. If I recall correctly, the TK83 did not have ULA but discrete logic as the ZX80 had.

The extra Kb was welcomed but did not make a big difference unless you could program in Z80 assembly language where 1Kb was a lot of more memory to do things. All those companies produced 16Kb RAM packs which also have the same issues the Sinclair RAM expansions had, hours of programming could be lost in a blink if the darn thing moved... So the usual solution, for the folks handy with a soldering iron, was to remove the board from the expansion and solder it straight to the main board.

I did not own a CZ1000 but a TS1000, at the time I bought it I was a young guy starting to learn electronics at a technical high school in Argentina. After going through the user manual and learning BASIC and I could not fail to notice the weird writing at the right side of the character codes in the Appendix A of the manual. HEX? Z80 Assembler? After CBh? I actually had to go to the Engineering Faculty of the University in the city I live to find out! There, a physics proffesor, an Electrical Engineer, explained the meaning of all that to me and pointed me to the right literature...

... 30+ years later I am still proffiting from what the TS1000 taught me. Countless nights spent (or is it invested?) trying machine code routines. I even managed to fit a Pac-Man like game in the available Kb! Awesome. Years later, I was able to apply the memory saving techniques and smart programming when writing firmware for the very limited Microchip PIC microcontrollers...

Many thanks to Sir Clive!