|Operating system||Sinclair BASIC|
|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.
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 However, the Dubna 48K and many other Z80 clones, hopelessly outdated by that time, were largely introduced in high schools of the Soviet Union.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.
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:
- 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, 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
A device named Dubna 48K is referenced in the American film Jason Bourne (2016). In the film, rogue agent Nicky Parsons uses a "palm-sized authentication device" named Dubna 48K to get connected to the mainframe computer of the Central Intelligence Agency (CIA). Parsons downloads all the files on the Agency's black operations. The Agency later finds out that the Dubna 48K unit was reportedly destroyed back in 1993, and its access to the mainframe was never revoked. The Agency did not know that it had actually survived its reported destruction. The film does not explain how a device from the 1990s could be still compatible with a mainframe computer of the 2010s. The film also does not point out that the real Dubna 48K was a Soviet home computer which was primarily used to play ports of video games. The video games available to the real Dubna 48K were released by Nintendo and were products of the third generation of video game consoles (8-bit era). 
|Wikimedia Commons has media related to Dubna 48K.|
- Captain, Sean. "Mission Impossible: The Ridiculous Tech Of Jason Bourne". Fast Company.
Parsons connects through a palm-sized authentication device called Dubna 48K. The CIA notices the attack, and IDs the unit as one that was supposed to have been destroyed in 1993. “Sounds kind of careless of the CIA to not revoke its access, especially to parts of its network which carry details of top secret covert ops,” says security analyst Graham Cluley in an email. And how is a 23-year-old device still compatible? Small concerns compared to the fact that the real Dubna 48K was an underpowered Soviet PC used to play ports of 8-bit Nintendo games.