Making Asteroids Miniature

Asteroids

Mini arcade cabinet builds are fairly common, but we’ve never seen anything like [Jurgen]‘s mini vector Asteroids cabinet that takes an original Asteroids circuit board and a true vector monitor and shrinks it down to table top size.

Unlike the raster monitors of a later generation’s arcade games, the original Asteroids cabinet used a vector monitor just like one would find in an oscilloscope. [Jurgen] found the perfect CRT in, of all places, a broken Vectrex console. The video circuitry in the Vectrex was rather primitive and the beam deflection was far too slow for the video signals generated by the Asteroids PCB. To get around this, [Jurgen] added a custom XY driver board. While the Asteroids game – and other vector Atari games – were designed for a screen with 1 MHz of bandwidth, [Jurgen] found that 300 kHz was ‘good enough’ to display proper Asteroids graphics.

While the cabinet isn’t a miniaturized version of any proper cabinet, [Jurgen] did manage to build a rather nice looking case for his luggable version of Asteroids. The exposed PCB on the back is a great touch, and an awesome project for any ancient video game aficionado.

Comments

  1. HomelyPoet says:

    300 kHz bandwidth, not 300 MHz, was deemed ‘good enough’.

  2. Geebles says:

    I think you mean “300 KHz” rather than MHz!

  3. Arnuschky says:

    Beautiful project. Quite impressive.

  4. Hirudinea says:

    I demand a video!

  5. Guesser says:

    That’s because a vectrex isn’t a “real” vector display. It’s a regular tv tube, magnetically scanned so a long way off being the perfect CRT for the job ;)

    • Eric Chapin says:

      FWIW Vectrex was a hack job in the end. Originally it was meant to have 5″ CRT but Milton Bradley wanted bigger so the dev shoehorned a 9″ CRT in without doing much change in the supporting hardware. As a result, the dual op amp that controls the deflection yoke is prone to burning out and there’s no suitable replacement today for that dual op amp chip.

      Neat mini arcade work, especially with original mainboard. I have an iCade that I got for only $15 new (blowout sale from Khol’s, 90% off regular price, they are long gone so don’t ask me to get some) that I might convert to something like this. I loved Tempest but it’d be tricky to get a proper color CRT for that. Maybe I’d try for original Star Wars arcade game in monochrome?

    • Jurgen says:

      I wouldn’t say that the Vectrex monitor is not a “real” vector monitor. All vector arcade machines used regular CRTs with magnetic deflection, just like the Vectrex. The Vectrex has a regular video CRT, but with custom deflection coils to enable the same slew rate for X and Y, just like the big arcade machines. It just skimps on the deflection driver (amplifier), which is essentially a stereo audio amp with much lower speed.

      Glad you folks like my Asteroids mini build!

  6. Matt says:

    I wonder if this deflection board would fix the Vectrex wobbly screen issue?

    • Chris C. says:

      [Jurgen] noted some minor wobble in his build, so probably not. He speculated it was caused by the difference between the 50hz powerline and 60hz refresh rate. I’d first see if it’s a magnetic field being thrown by the Vectrex transformer he reused, and picked up by the monitor – which I’d assume would be worse in a complete Vectrex due to closer proximity, at refresh rates other than powerline frequency.

  7. Chris C. says:

    Well built and documented. I like it.

    I explored his server and saw he is (or was) working on a scanning tunneling microscope as well.

  8. Dr D says:

    They never got to the bottom of why the sequel to Asteroids, a sit down version of the game called Hemerhoids was panned.

  9. Finally! One of these miniaturized cabs, actually using the original PCBs! :D

    And of course, it just wouldn’t be the same without a real vector CRT, so kudos on that, too!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 93,839 other followers