---
title: ELEKTOR Junior Computer
categories:
- Computers
types:
- Home Computer
origins:
- Germany
years:
- '1980'
cpus:
- Rockwell 6502
params:
  name: Junior Computer
  image: /media/museum/photos/junior-computers_1_350px.jpg
  company: /companies/elektor
  company_name: ELEKTOR
  specs:
  - label: NAME
    value: Junior Computer
  - label: MANUFACTURER
    value: Elektor
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: Germany
  - label: YEAR
    value: '1980'
  - label: BUILT IN LANGUAGE
    value: Monitor
  - label: KEYBOARD
    value: 23 keys hexadecimal keyboard
  - label: CPU
    value: Rockwell 6502
  - label: SPEED
    value: 1 MHz
  - label: CO-PROCESSOR
    value: PIA 6532 and EPROM 2708 (1K)
  - label: RAM
    value: 1 Kb RAM + 128 bytes from the PIA 6532
  - label: ROM
    value: 1 Kb EPROM (monitor)
  - label: TEXT MODES
    value: seven segments LED display x 6
  - label: GRAPHIC MODES
    value: None
  - label: COLORS
    value: None
  - label: SOUND
    value: None
  - label: I/O PORTS
    value: Port connector (31 pins), Expansion connector (64 pins)
  - label: POWER SUPPLY
    value: External power supply (+5v, +12v, -5v)
  tabs:
  - photos
  - links
  forum_thread: 1292
  photos:
  - title: JUNIOR COMPUTER
    subtitle: ''
    text: |-
      Complete system with power supply board

      Thanks to Denis Faivre for this picture
    image: null
  - title: MOTHERBOARD
    subtitle: ''
    text: Thanks to Denis Faivre for this picture
    image: null
  - title: JUNIOR COMPUTER
    subtitle: ''
    text: Thanks to http://retro.hansotten.nl/ for this picture
    image: null
  - title: JUNIOR COMPUTER IN A WOODEN CASE
    subtitle: ''
    text: Thanks to http://retro.hansotten.nl/ for this picture
    image: null
  - title: ORIGINAL ARTICLE FROM ELEKTUUR
    subtitle: ''
    text: dated march 1980
    image: null
  links:
  - title: Retro Computing / About small SBC systems
    url: http://retro.hansotten.nl/6502-sbc/elektuur-junior/
    text: Hans Otten website, full info information about 8-bit small computer systems computing and electronics, including the Junior Computer
  oc_id: 1327
  source:
    url: https://web.archive.org/web/20221204084526/http://www.old-computers.com/museum/computer.asp?c=1327
    date: '2022-12-04'
---

The Junior computer design was published by Elektuur/Elektor magazine from 1980 on. It was published in a series of magazine articles, four books and several socalled paperware A4 booklets. Loys Nachtmann designed and developed the the Junior Computer. G.H. Nachbar did the Dutch translation of the German books. The 4 Junior books were translated into English, German, Spanish, Italian and French as well.

The Junior design is in fact heavily inspired by the hardware of the [KIM-1](/museum/mos-technology-kim-1/) (or call it a clone ..). It didn't use though the 6530 specialised chip from MOS Technology (I/O + ROM), but rather the PIA 6532 and an EPROM 2708. The floppy interface design was based on the Ohio Scientific OS65D design.

It was delivered as a kit or could be be built from only the PCB’s sold by Elektuur. Many hobbyist have build one. Later extended with an adapted version of the 8K KB9 Basic and even a disk operating system (Ohio Scientific DOS OS65D).

Many expansion cards were available. These include an input-output board (including a VIA 6522, a tape interface and an RS232 port), a VDU (video terminal) card (actually an evolution of elekterminal), an EPROM/SRAM card, a 16/64 KB DRAM card, an EPROM programmer board and even a floppy drive controller based on the Ohio Scientific DOS OS65D.

A BASIC interpreter was also available, derived from Microsoft's KB94.

Many Junior Computers were built, either from the PCB made by Elektuur and separate components or as a complete kit.

---

Thanks to Denis Faivre for the pictures and to retro.hansotten.nl for some of the info.