---
title: MARK-8 Minicomputer
categories:
- Computers
types:
- Home Computer
origins:
- U.S.A.
years:
- '1974'
cpus:
- Intel 8008
params:
  name: Minicomputer
  company: /companies/mark-8
  company_name: MARK-8
  specs:
  - label: NAME
    value: Minicomputer
  - label: MANUFACTURER
    value: Mark-8
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: July 1974
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: 16 switches on front panel
  - label: CPU
    value: Intel 8008
  - label: SPEED
    value: 0.5 Mhz
  - label: CO-PROCESSOR
    value: None
  - label: RAM
    value: 256 bytes
  - label: ROM
    value: None
  - label: TEXT MODES
    value: No display interface
  - label: SOUND
    value: No sound interface
  - label: I/O PORTS
    value: 1 x I/O port
  - label: BUILT IN MEDIA
    value: None
  - label: POWER SUPPLY
    value: External power supply
  - label: PRICE
    value: About $300
  tabs:
  - photos
  photos:
  - title: MANUALS & SHEMAS
    subtitle: ''
    text: Mark-8 with Jon Titus instruction manual and circuit diagrams.
    image: null
  - title: CASE KIT
    subtitle: ''
    text: The case and board kit as it was received from Techniques Inc, of Englewood.
    image: null
  - title: BACK SIDE
    subtitle: ''
    text: Power supply back panel and logic boards
    image: null
  - title: RADIO-ELECTRONICS MAGAZINE
    subtitle: ''
    text: front cover of the July 1974 issue of Radio-Electronics magazine where the Mark-8 computer appeared for the first time.
    image: null
  comments:
  - author: Achim Baqué
    date: Sunday 12th September 2021
    text: Hi, I am a vintage computer collector. Please contact me (E-Mail via my website) if you have the Mark-8 to offer.
  - author: Erik Jordan (USA)
    date: Friday 28th September 2007
    text: |-
      Mr. Titus later wrote a book on how to custom-build a computer based on the 8085A processor called the "8085A Cookbook".

      It is part of the Blacksburg Continuing Education Series and was published by Howard W. Sama & Co Inc., out of Indianapolis. Mine is 1st Ed, 3rd Printing, 1982.

      at 350 pages, it is an interesting little book...while not directly related to this computer, it is the brainchild of its creator, and I invite the editors to place this snippet wherever they deem appropriate.
  oc_id: 741
  source:
    url: https://web.archive.org/web/20230529194732/http://www.old-computers.com/museum/computer.asp?c=741
    date: '2023-05-29'
---

**"Build your own Mark-8"**. This title appeared on the front cover of the July issue 1974 of an electronic hobbyist magazine called **Radio-Electronics.**

The Mark-8 was an Intel 8008 / 256 bytes RAM memory based system without neither ROM monitor, power supply, case, video, keyboard, nor backup interface. Consequently, the user had to enter program instructions each time he turned the system on.

To build this computer, the home computing fanatic had first to buy for $5.50 the 48 pages instruction manual written by **Jon Titus**, the creator of the system, from Radio Electronics. Then order the circuit board from an Englewood, New Jersey based company for $47.50, and finally provide himself with various components, including the Intel 8008 processor for about $250. About 7500 home computing fanatics ordered the instruction manual and 400 of them the main board. Very few of them succeeded in running the final assembled system as it was a very long and full of traps job.

The LED display featured 4 rows of 8 leds. The two upper rows displayed the address bus (14 leds) and processor cycle state (2 leds). The third row displays an 8-bit memory data, and the fourth, the 8-bit value available from the output port 0.

Most of the fanatics who tried to bring the Mark-8 to a running state gave up and bought a few months later the first versions of the [Altair 8800](/museum/mits-altair-8800/), the first real personal home computer.

If you want to learn more about the Mark-8 computer, you should read the [page](http://www.his.com/~jlewczyk/adavie/mark8b.html) written by Jon Titus, the Mark-8 designer.

**To note:** Pictures of this page show a Replica version of the Mark-8, not an original system. The Replica was made by Steve Gabaly of Apalacia, NY and sold in the late 2000.\
Original pictures needed!