Orion (Homebrew)

Manufacturer RLV Electronics (Homebrew)
Model System Orion
Serial Number Homebrew
Processor / Clock Speed 8080 / 2 Mhz
RAM Base / RAM Maximum 1K / 64K
Storage Audio Tape
Operating System ROM Monitor
Display / Resolution Composite video / 80x24 text chars (Motorola 6845 controller)
Expansion Non-standard bus

A homebrew system, based on simplified schematics from a Popular Science article. Originally had to be bootstrap loaded from hand turned hex rotary switches (8 bits Address and and 8 bits Data), then CPU would jump to address 0. Later burned a boot ROM, and supported a ROM monitor and audio cassette data storage with a hand built modem. Case was hand constructed from an aluminum minibox base, and extended vertically with hand constructed plates. Teak formica trim creates a nice contrast to the oven-baked black enameled sides.

Inside of the orion system.
The System Orion logo. Each component was named after a star in the Orion constellation. I can still recall riding in my family's 1964 Ford Galaxy 500 wagon on clear nights and watching my favorite constellation out the windows. Betelgeux: main unit, Bellatrix: keyboard, Alnitak: printer, etc. That's not the real car, but the only image I could find of one. Ghostly apparitions are my handiwork to make the car look original. Ours was desert tan with woodie paneling (plastic simulated).
The system monitor. A handbuilt case surround a retuned display scavenged from an old non-standard terminal. The tinted plexiglass faceplate is from that terminal and still retains the letters "DATA/SCOPE", to which I added my initials.
The system keyboard. Now let's get crazy! This is a case from another keyboard with an IBM terminal keyboard retrofitted.
Only one example of the individual component nameplates.
The keyboard back gives away how wierd this was. This keyboard required negative voltages that service IBM technologies of the time, so there's a dedictaed regulator and heat sink handing off the back. Also note the keyboard CPU reset button (it really needed advanced power cycling that I didn't create) and a special caplock switch.
The CPU board with an intel 8080 CPU, running at 2 MHz. Wow! The system boot ROM is to the right and is dated 7/22/83. The cards are from IBM Mainframe surplus and plug into a special IBM motherboard. My Dad supplied these throw-outs from IBM Poughkeepsie.
A view of the back of the CPU board showing the classic wire-wrap connection technology. A hobbyist like myself could easily use a cheap hand tool to make reliable connections. For periods of heavy assembly, my Dad borrowed an electric wrapper for me.
The static RAM board. Originally 256 words of 16 bytes, later changed to 1024x16-bit.
The video controller board based on the motorola 6845 chip. The video sync rates were tunable from internal registers. Characters were from my own hand-burned ROM. Later this system could display the APL language character set when I burned the second half of the ROM with characters. I created a small assemnbly language character editor for the purpose.
The original I/O board providing input from an older keyboard (not shown), and also driving a hexadecimal display.
A serial communication board. Originally just the left quarter, provided a low speed audio MODEM built of hand tuned oscillators and filters to allow data storage on audio cassette tapes. Later the remainder was added to provide two conventional serial ports to allow this system to use the bellatrix keyboard, and to also perform as a termina connected to a regular external accoustic coupled 300 baud modem, dialed into a mainframe.

rPCm