Vectrex - hack

Found a second Vectrex. :-)
I have two now, one to play and the second to use  for vector rescanning.
This has come all the way from France.

As a retro gaming collector, it hurts to modify this. So I'll try to make as few changes as possible.

Time to open her up.

Be very very careful of the tube. Even after not being powered for weeks they can still retain lethal voltages. So discharge it first.

I used this screwdriver (place under the protective rubber CRT cap) which I attached to ground via the alligator clip. Listen for the pop !
I can't stress enough the risk of discharging the tube. If you are not sure what to do , get a qualified technician. These voltages can kill.

Some pics .. this is the CPU section

In the pic below, the CPU section is on the base, and the XYZ driver board is positioned vertically. It is to the left of the tube.

The CPU is connected to the XYZ driver board in the un-modified vectrex

The CPU is what creates the images.

 In the pics below, the XYZ board lies behind the heatsink.

You need to separate these two boards. and wire the XYZ inputs to the back.
I'll use 3.5mm jacks.

Another view of the CPU board. The Red, Blue & Yellow connector is the XYZ connector.

Unplug this.

..

Rather than cut the female XYZ connector ive decided to use a header to make a new male connector 

 

It may look confusing, that I have 6 jacks .

3 connect to the CPU, and 3 connect to the XYZ driver board.

..

The pic below is the inside of the case. First, connect all the grounds. 

 

In modifying the vectrex, what I am doing is finding a way to replace the CPU's control voltages with control voltages from a modular synthesizer.

 

So most people just cut the 3 leads leading to the XYZ driver board and connect that to the modular synth.

This is fine , however, the CPU is now useless... and you can no longer play games, unless you reopen the vectrex and reconnect everything.

 

Below is the outside of the case.

..

All I have done is bring the 3 wires that connect to the CPU , to the back of the machine and attached 3.5mm jacks. (The ones on the left)

 

I have also brought the 3 wires that connect to the driver board , to the back of the machine. and attached 3.5mm jacks. (The ones on the right)

 

So if I wish to connect a modular synth, use the 3 jacks on the right (DONT connect to the left).

 

The (3 right) X,Y,Z inputs are CV inputs to the driver board.

I understand that 0V (on both X and Y) its the centre and that

±9V works on the on the horizontal X input and ±11V on the vertical Y input.

... to be tested.

 tHE green wire is ground.

The inside of the jacks

Connect like this to return the Vectrex to normal so you can play games again
I could instead add a switch, though this would involve more holes & drilling.

I've attempted to keep any destruction of this vectrex to a minimum.
So the only permanent modification was drilling the 6 holes for the 3.5mm jacks. All the original wiring is preserved!!! So you can re-connect the wiring for gaming action!

Now that you've modded it what standard eurorack audio modules should you use??
In my test I used:

The elby matrix mixer is a real winner. The bluelantern Thruzero VCO & the steiner microVCO also worked nicely.
Other possible modules:
+ Synovatron CV tools, DPO, MATHS, Wogglebug.
"Maths is usually the Z input, I'm mainly just playing with the speed of the pulse - as if it's a really fast envelope.
Then two or more outs from both oscillators in the DPO are going to X & Y,..."
+ e340 for X & Y. -- cloud generator
+ Thonk/Fonitronik Cascade 
+ If you have a ARP 2600 or a TTSH, the voltage processor is excellent for modifying the 3 input signals 
+ Pip Slope and an O/A/x2 from ALM / Busy Circuits
+ PDO and Akemie's Castle 
+ Clouds  
+ 4MS Shifting Inverting Signal Mingler  

A bit about vector rescanning

My understanding is that the vectrex isn't prefect for vector rescanning as it does not have the bandwidth ....but it kinda works in limited ways
It is better suited for lower frequency oscillographics.  

However, if you still want to do vector rescanning you need:
1.Video Input to extract luma from your video source
2. H & V ramps generator .

Thus if you are using Cadet modules you only need one Ramps, a Sync Gen and an Input. 
A LZX visual cortex (VC) has all of this.
Connect the horizontal ramp to the X, the vertical ramp to Y and the luma output (of the VC or the VideoInput) to the Z.
 
Links
+ Muffs- vector modification
+ Vectrex Hackaday
+ Hacking a vectrex - Lumpybanger
+ Zektor - using the vectrex monitor
+ Muffs - vector rescanning for dummies
+ Muffs - good oscilloscope for vector rescanning
+ Rutt-cadetra blog

---------------------------
Click here to access the Video Index page