Supriya Ghosh (Editor)

Dubna 48K

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Type
  
Home computer

Memory
  
48 KB

Operating system
  
Sinclair BASIC

Dubna 48K

Release date
  
1991; 26 years ago (1991)

CPU
  
analogue of Zilog Z80 @ 1.875 MHz

The Dubna 48K (Дубна 48К) is a Soviet clone of the ZX Spectrum home computer. It was based on an analogue of the Zilog Z80 microprocessor. Its name comes from Dubna, a town near Moscow where it was produced, and "48K" stands for 48 KBs of RAM.

Contents

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, and as such, wasn't suitable for "studying the principles of PC operation". However, the Dubna 48K and many other Z80 clones, hopelessly outdated by that time, were largely introduced in high schools of the Soviet Union.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.

    Included items

    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.

    Technical Details

  • CPU: 8-bit MME 80A, 1.875 MHz running at half speed of the original ZX Spectrum
  • RAM: 48 KB (16× КР565РУ5Г chips, see picture 4)
  • ROM: 16 KB (2× К573РФ4А, picture 3, two white chips in the middle)
  • Resolution: 192×256 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, 1.7 A
  • Dimensions of main unit: 47×320×240 mm
  • References

    Dubna 48K Wikipedia