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OHIO Scientific

When the C4P was launched, Ohio Scientific said that it was a giant step in the world of the home computers. It was twice as fast as an Apple ll or Commodore Pet and more than three times as fast as a Tandy TRS 80.
However, despite its technological lead, the C4P and other Ohio Scientific computers always suffered of a lack in efficient software and attractive handbooks. For this reason, very few third companies built cards and peripherals for the Challenger series. So, the C4P didn't withstand to the competition of the Apple II and II+ version which appeared 4 months later.
However, Ohio Scientific sold it until 1981 as a business oriented system.

In March 1981, OSI was sold to 'M/A-Com' company, but the name did continue until at least 1985. Some OSI based systems were also sold under the name OSITRON.

In 1979, two versions were sold:
The C4P basic version ($698) with:
- 8KB Basic ROM
- 8KB of static RAM expandable to 32KB
- Audio tape interface.
The C4P MF ($1695) with all the features of the C4P plus:
- 24KB RAM expandable to 48KB
- 5" floppy-disc drive unit
- Real time clock
- Interfaces for Home Security System, parallel printer, modem
- Bus connector.

Brett Molotsky reports:
The Challenger 4P was also sold for a VERY brief time by JCPenney stores in a consumer-friendly version. It had an all-plastic case that was a bit more sleek and that looked much like an Apple II case. That's where we bought ours, along with a black and white TV and a cassette tape player.

David Pelleg recalls:
The C4P was my first computer. It was great except it had ONE MAJOR DESIGN FLAW which anyone who ever used it would know quite well. That was the placement of the reset key directly adjacent to the (very small) enter key. One little touch of reset and EVERYTHING you had been working on was wiped out instantly. That is why I'm so paranoid about constantly saving files even today (where it takes ctrl-alt-delete plus "Are you sure you would like to restart?").

Please consider donating your old computer / videogame system to or one of our partners from anywhere in the world (Europe, America, Asia, etc.).


The very first program I ever sold, was to a guy named Cam. He paid me 20.00 to write it while I was still in college. Written for the IIP I think. I still have a cassette of it. Sneaky Snake. The basic premise was a random number popped up on the screen in a random spot. you had to move your snake with the arrow keys to get to the number and eat it. Then the snake would grow by 1 segment. The snake always followed it''s track, so as you moved it I had to locate and erase the last segment of the snake. The goal was to get the snake as long as possible. I especially loved the tank characters. This machine had a set of characters in the character set that were a tank, oriented in 8 different directions. It made writing tank style games really nifty. I obtained one of these from a friend back in the late 80''s. It, along with some other ancient machines, is still sitting in a box in my storage trailer....
One of these days I''m gonna dig it out and see if it still runs. Still one of my favorite old systems.

Wednesday 20th March 2013

Bought a C24P in 78...was a far superior unit to the Apple but they didn''t help out with program development and that was their downfall..along with not supplying them to colleges and universities like apple did...brilliant marketing move on their part... 19 years later walked into the control room for a nuclear fuel processing site and about fell over when I saw about 20 of these units humming along with the monitors displaying every move they made... turns out they had been controlling the operation for 10 years with no shutdowns of the plant...they were controlling every piece of the operation... temps, valves, switches, etc.... according to them the machines were bullet proof with extremely high reliability, etc.. a shame the company went belly up... I would have loved to see what they could have developed...

Wednesday 24th November 2010

exacte e-mail

Monday 18th October 2004
daniel (fr)


TYPE  Professional Computer
YEAR  1979
BUILT IN LANGUAGE  Basic interpreter
KEYBOARD  Full stroke keyboard - 53 keys
CPU  6502 or 6502C (GT option)
SPEED  2 Mhz.
RAM  8 KB expandable to 48 KB
ROM  8 KB (Basic interpreter)
TEXT MODES  32 lines x 64 char.
SOUND  Tone generator and sound digital/analog converter
SIZE / WEIGHT  Unknown
I/O PORTS  Audio tape, modem, parallel printer, Bus
POWER SUPPLY  Internal Power supply
PERIPHERALS  F.D. unit, joysticks
PRICE  $698 (C4P), $1695 (C4P MF)

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