Dubna 48K

The Dubna 48K (Дубна 48К) is a Soviet clone of the ZX Spectrum home computer launched in 1991. It was based on an analogue of the Zilog Z80 microprocessor. Its name comes from Dubna, a town near Moscow, where it was produced on the "TENSOR" instrument factory, and "48K" stands for 48 KBs of RAM. According to the manual, this computer was intended for: studying the principles of PC operation various kinds of calculations "intellectual games" By the time this computer was released (1991), there were already much more powerful x86 CPUs and commercially available advanced operating systems, such as Unix, DOS and Windows. The Dubna 48K had only a built-in BASIC interpreter, and loaded its programs from a cassette recorder, so it couldn't run any of the modern operating systems. However, the Dubna 48K and many other Z80 clones, though outdated by that time, were introduced in high schools of the Soviet Union. Many of the games for the Z80-based machine were ported from games already available for Nintendo's 8-bit game console, marketed in Russia under the brand Dendy. The machine comes in two versions: in a metal case for the initial 1991 model, and in a plastic case for the 1992 model. The Dubna 48K was shipped with the following units: Main unit ("data processing unit", as stated on its back side), with mainboard and built-in keyboard External power unit Video adapter for connecting the computer to the TV set BASIC programming manual Reference book, including complete schematic circuit Additionally, there were some optional items: Joystick 32 cm (12") colour monitor The computer could also connect to a ZX Microdrive, but such device was never included. CPU: 8-bit MME 80A at 1.875 MHz (half the speed of the original ZX Spectrum) RAM: 48 KB (16× КР565РУ5Г chips) ROM: 16 KB (2× К573РФ4А) Resolution: 256 x 192 pixels, or 24 rows of 32 characters each Number of colours: 8 colours in either normal or bright mode, which gives 15 shades (black is the same in both modes) Power unit: 5V, 1.