---
title: ISOT EC-1035
categories:
- Computers
types:
- Professional Computer
origins:
- Bulgaria
years:
- '1977'
cpus:
- ES-2635
params:
  name: EC-1035
  company: /companies/isot
  company_name: ISOT
  specs:
  - label: NAME
    value: EC-1035
  - label: MANUFACTURER
    value: ISOT
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: Bulgaria
  - label: YEAR
    value: '1977'
  - label: END OF PRODUCTION
    value: Unknown
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: Terminal keyboard
  - label: CPU
    value: ES-2635 (?)
  - label: SPEED
    value: 160 000 operations per second
  - label: RAM
    value: 256 to 512 KB. 16 MB virtual memory max.
  - label: ROM
    value: BIOS in ROM, size unknown
  - label: TEXT MODES
    value: Depends on the terminal used
  - label: GRAPHIC MODES
    value: Graphic capabilities with some ISOT video terminals
  - label: SIZE / WEIGHT
    value: 100 square meters!
  - label: BUILT IN MEDIA
    value: Magnetic tapes. Recording speed of 120 KB per sec.
  - label: OS
    value: ES-DOS dedicated O.S.
  - label: POWER SUPPLY
    value: Tree-phase current - 220/380V 100A
  - label: PERIPHERALS
    value: I/O Multiplexer ISOT 8401 for serial and Parallel peripherals
  tabs:
  - photos
  - hardware
  photos:
  - title: ISOT BROCHURE
    subtitle: ''
    text: ''
    image: null
  - title: OTHER ISOT SYSTEMS
    subtitle: ''
    text: |-
      ISOT also made several 8-bit and 16-bit desktop computers, among them:\
      • **1030C** 8086 based CAD system\
      • **1031C** Z80 - CP/M system\
      • **1039C** (also named CM-4) 16-bit multitasking system\
      • **1036C** PC compatible system based on the Bulgarian CM688 processor, compatible with the Intel 8088. Here pictured with the **ISOT 6305C** 132-col. 150 cps dot-matrix printer.

      Thanks to **Bojidar Stefanov**
    image: null
  hardware:
  - title: ISOT 8015 MODEM
    subtitle: ''
    text: |-
      4800-baud modem which was connected to several Bulgarian mainframes.

      Thanks to **Bojidar Stefanov**
    image: null
  comments:
  - author: oldboy
    date: Thursday 22nd November 2012
    text: |-
      This was an IBM370 series compatible computer.\
      We used it with IBM-DOS/VS-POWER system.
  - author: Dave Witt (Canada)
    date: Saturday 17th March 2012
    text: Probably because EC in Cyrillic looks like ES in Latin alphabet
  - author: Thomsonicus (Poland)
    date: Wednesday 12th December 2007
    text: hmm, the name says EC-1035 but the brochure states that it's a ES-1035... weird
  - author: Linkman (Slovak Republic)
    date: Friday 22nd April 2005
    text: I wanna know how big is this computer ?
  oc_id: 978
  source:
    url: https://web.archive.org/web/20230510155754/http://www.old-computers.com/museum/computer.asp?c=978
    date: '2023-05-10'
---

Very little information about this Bulgarian mainframe used by big East European companies as an industrial or information management system.

It was partially compatible with IBM mainframe and could also share programs and data with the russian **Minsk-32**. It could run in multiprogram mode thanks to its virtual memory.

The ISOT brand name means 'State Economic Alliance'

Thanks to **Bojidar Stefanov** for information and picture.

<table> <tr> <td></td> <td>We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.</td> <td></td> </tr> </table>