Sinclair developed the ZX Spectrum 128 (code-named Derby) in conjunction with their Spanish distributor Investrónica. Investrónica had helped adapt the ZX Spectrum+ to the Spanish market after the Spanish government introduced a special tax on all computers with 64 KB RAM or less which did not support the Spanish alphabet (including ñ) and show messages in Spanish.
New features included 128 KB RAM, three-channel audio via the AY-3-8912 chip, MIDI compatibility, an RS-232 serial port, an RGB monitor port, 32 KB of ROM including an improved BASIC editor and an external keypad.
The machine was simultaneously presented for the first time and launched in September 1985 at the SIMO '85 trade show in Spain, with a price of 44,250 pesetas. Because of the large amount of unsold Spectrum+ models, Sinclair decided not to start selling in the UK until January 1986 at a price of £179.95. No external keypad was available for the UK release, although the ROM routines to utilise it and the port itself, which was hastily renamed "AUX", remained
CPU Zilog Z80 A
SPEED 3.5469MHz
RAM 128kb
ROM 32kb (16k 48k Basic + 16k 128k Basic)
TEXT MODES 32 x 24
GRAPHIC MODES 256 x 192
COLORS 8 with two tones each (normal and bright)
SOUND 3 channels, 7 octaves (Yamaha AY-3-8912)
SIZE / WEIGHT 320 x 150 x 45 mm
Photograph © Bill Bertram 2006
Our model was kindly donated by Paula from Norfolk
