Spectrum - Vintage Sinclair

The ZX Spectrum was released on 23rd April 1982 as the successor to the ZX81. The name Spectrum was to highlight the new colour screen capability. Originally launched with 16K of RAM, there would ultimately be 8 different models between 1982 and 1987, finally ending production in 1992 after selling 5 million units. Its rivals in the early '80s were the BBC Micro and Commodore 64.

The 16K model originally sold for £125, later reduced to £99. It was remembered for its distinctive rubber keys and rainbow design.
About 60,000 of the Issue 1 models with the light-grey keys were sold. The later model had blue-grey keys.

Specification:

8-bit Z80 processor running at 3.5MHz
16K ROM (Sinclair Basic)
Video : RF modulator for output to a TV
Display : 32 columns X 24 rows
Sound : Internal bleeper giving 10 octaves
Ports : Bus expansion via edge connector
3.5 mm audio in/out for cassette recorder

Dimensions : 233(W) X 144 (H) X 30 (D)
Weight : 550 grams

Because all the BASIC key words had to be entered with single key strokes, each key had up to 5 different options.
These were selected by using the various cursor modes of K (Keyword), L (Line), C (Caps) and E (extended mode).

Start-up screen.

A simple program to draw random lines.