This dates from 1982.
Vectrex was the first company to bring vector graphics to the home audience via a vector monitor.
This was a time when most arcade games used vector graphics. (for instance in Asteroids and Space War), different from the raster technique used in most home video games that connected to televisions. Vector graphics are essentially lines of light. Raster graphics consist of small pixels or blocks.
The built in game, Minestorm is a derivative of Asteriods.
I remember playing asteriods on an Atari back in those days and the vectrex is probably the closest thing I'll get to experience this today, short of buying a vintage arcade machine.
This video is a very cool... recreating asteiods with lasers:
https://www.youtube.com/watch?v=FkHjG759ABY
So I'm lucky to have found a working vectrex.
Considering if I should mod it or leave it alone.
Will probably mod it.
I'm interested in using the monitor for video synthesis.
One peripherial I don't have is the light pen.
There are however a few sites with hacks for making my own.
http://www.playvectrex.com/vectech/mvlp/mvlp_f.htm
and:
https://www.youtube.com/watch?v=6On2AFPx6pc
The working end of the pen is a cheap silicon L14G3 phototransistor
The other periphery are the 3D glasses.
...so so rare. This 3D system predated the Sega Master System's SegaScope 3D by about four years.
The monitor is Black & white.
Every game came with its own coloured and transparent overlay, that could be attached to the screen.
Specs:
Manufacturer: Western Technologies/Smith Engineering which was a videogame company started by Jay Smith, an engineer who was previously an employee at Mattel. It was licensed and distributed first by General Consumer Electric (GCE), and then by Milton Bradley Company after their purchase of GCE.
The Vectrex was known as Bandai Vectrex Kousokusen in Japan.
Release year: 1982
Discontinued :1984
MPU: Motorola 68A09 (MPU= Microprocessor)
On the actual PCB it's IC206.
Frequency: The MPU operates at 1.6 MHz from a 6 MHz external Xtal.
An internal divide by 4 circuit generates the MPU 1.6 MHz "E" clock signal
used in the system
ROM: 8KB (one 8-bit 2363 chip) , 4KB used by Minestorm.
On the actual pcb the ROM chip is IC201. It's the sharp 284001-1
RAM: 2 x 1KB (two 4-bit 2114 chips). These RAMS provide storage locations for data
indicative of locations of objects, game status, and various other information
needed by the microprocessor during game operation. (IC 204 & 205)
Sound: 3 channels through a General Instrument AY-3-8912 sound chip
You will find this chip on the Logic board. It's IC 208.
3" electrodynamic paper cone speaker.
3 voices (all square wave). 1 noise generator
Media: ROM cartridges 32KB
Display : 9 x 11 inch CRT (240mm diagonal), Black & White monitor. Samsung model 240RB40
Resolution: 330 × 410
WEIGHT: 15 Lbs.
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The standard TTL device types 74LS00 and 74LS32 are used as control line decoders to allow the MPU to select the appropriate circuit element to be addressed at any particular time.
The 74LS32 decodes logic to perform read and write access to the RAM by the processor . The 74LS32 is a Quad-ORgate. (IC203). Its obsolete so you have have trouble finding replacements.
The 74LS00 is a 2/IN NAND gate. (IC202) .
**Any TTL chips you find with the code 74LSxx are Low power Schottky and date pre 1985.
They were superceeded by chips using the code 74ASxx - Advanced Schottky.
TTL stands for Transistor–transistor logic. Its a logic family built from bipolar junction transistors. Its name signifies that transistors perform both the logic function (the first "transistor") and the amplifying function (the second "transistor")**
The analog processing section includes digital to analog converter (DAC) chip type MC1408, dual 4 channel multiplexer/demultiplexer chip type CD4052, and dual channel op-amps types LF353 and LF347.
The DAC chip (Digital to Analogue Converter) MC1408 receives an 8 bit word at data terminals D0-D7. DAC output (pin 4) is current source. This IC is responsible for graphic output
One section of IC LF353 is used to change this current to a voltage representative of the 8 bit digital word received by the DAC chip. The LF353 voltage is applied to an input of the dual 4 channel CMOS multiplexer (MUX) chip CD4052. This same voltage (designated "DAC" on the schematic) is the X-axis drive signal.
The CD4052 MUX chip serves two purposes: it selectively couples, under MPU control, the output of the DAC current/voltage converter to one of 4 places and is used to selectively couple the inputs from the joystick pots to the voltage comparator IC LF353.
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If you are having any problems with the joystick interface try replacing the AY-3-8912 sound chip.
You would think that the 6522 Versatile Interface Adapter (VIA) is the obvious choice for the joystick interface, but it turns out to be connected to the General Instrument AY-3-8912 which also has an 8 bit IO port.
(The above information is from the Vectrex technicial manual).
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