"The waveshape is similar to the 245 but the baseline sits at 4V,
not 2V (I believe) due to the number of stages. When all the
stage pulse output resistors were changed to 6K8, the module would no longer advance."
To fix this issue adjust the clock waveshape trimmers until it functions
reliably.
This is the waveshaper section on PCB2. Change R301to a 10K trimmer.
PCB2 Change R306 & R315 to a 20K trimmer (wiper at the node connecting R306 & R315).
Photo x 2 *
--------------------------------
Diodes
Looks like they are all standard 1N457
D1, D2, D3, D4, D5, D6, D7, D8, D9, D10
mouser 512-1N457
10K resistors first
1K resistors, etc etc
------------------------------------------------
100K trimmers
mouser 858-25PR100KLF
I used a different footprint one on TR2
still 100k
----------------------------------
Time to install the transistors
Don't install Q75, Q76, Q77, Q79.
These are 2N3906
Connect the base to the collector with a link on Q75, Q76, Q77, Q79.
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.
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.
It's a DIP-40 8-BIT MICROPROCESSING UNIT. 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.
------------------------------------------------------------------------------------------------------- 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. -------------------------------------- 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).
I've had this PCB/panel for 4 years... finally getting around to building this.
I finished the companion to this about a year ago, the CellF action.
These two panels were developed for the cellF neural synth project where a synthesizer was made to be controlled by live human neuron cells.
Some pics of the virgin PCBs The CellF action build uses smd resistors, caps & ICs. All transistors are thru-hole.
The PCB is very large
Each board has. 2 tri-core VCOs 2 LFOs 2 LPGs 3 VCAs VC spring reverb diff-rectifier jerkoff chaos 2 281 EGs Sauce of Unce. Pots and sockets mount on PCB, no wiring (except to reverb tank).
I'm building version 2.0
I usually put on the ICs first, as these are the most fiddly.
Regarding the NJM13700 .
I'm using regular LM13700 SOIC . they will fit (in addition to some NJM13700s) These are transconductance amplifiers.
I'm using 470 ohm resistors for the LED resistors (RL)
There are 2 CMOS chips used in the build: 4001 & 4066
Using these 10V zeiners
The 10V voltage regulator: 7810
JFETS: using J112 x 4
Vactrols:
Using 2 types:
The single vactrol NSL. the white dot marks the cathode.
VTL 5c3/2..... I used them a lot in the buchla "clones"
The sloped edge marks the cathode. The cathode is labeled on the PCB with a K.
The Dual LED has a common Cathode. Its orientation doesn't matter.
Check the led fits in the panel hole before putting it
all together. I had a batch of duals that were a bit big and the needed
0.5mm drilled out.
...
..
