MAKE YOUR OWN SLOT MACHINE
COIN
MECHANISMS
CONTROL
SOUND/ VIDEO AND COMPUTERS
Adding sound, video and computers
The simplest and cheapest way to add sound
and video to a slot machine or siulator is to use modified domestic CD and DVD
players. I simply solder wires to the contacts of the play and next track
buttons to jump between tracks - and switch the power off at the end of each
cycle to reset everything.
Sound
Boom boxes (CD player,
amp and speakers) cost about £20. There is a delay of about 6 seconds between
power on and it playing, but it is possible to record the first track blank so
the machine just has to skip to the next track when a coin is inserted. You
obviously need some sound software on your computer, and a CD burner to master
your CD.
It is also possible to use MP3 players, though these tend to be fiddly to
connect the wires to – and often start up at a very low default volume. There
are also solid state sound chips. Kits based round these chips are sold by
Maplin electronics. The chips are principally made for telephone voicemail
recordings so the quality is not as good as CDs and the time is limited to a
minute or two.
My latest sound system uses MP3 running on a DV 68 video player (for details see
under video). This manages to keep one of twelve tracks playing at the right
moment, even when they are rapidly and randomly changing, which I find very
impressive. For playing a single track, I'm currently using the eyezup
media player (see video).
For sound accompanying video, computer speakers are good value. These will plug
into the phono audio out sockets of a DVD player (which obviously plays the
sound with the picture). A bass speaker and amp with two satellite speakers cost
about £20. It doesn’t matter where the bass speaker is but the tweeters need
to as close to the ears of the people using the machine as possible. This
enables the sound to be easily audible without being played at high volume –
which pollutes the rest of the space (conventional amusement arcades never seem
to have applied this simple lesson).
Video
Video keeps getting cheaper and easier to incorporate. Until recently, I ran the video animation for my simulator rides from set top DVD players (now about £30). Starting the DVD playing at the same time as the main controller, they keep perfectly in sync as their internal timing circuits are both quartz controlled.
My first simulators ran using the Video CD format. The quality is amazingly good for a frame size of 320x480. Video material has to be converted to MPEG1 format (I use a program called Tempgnc). Then in the menu of your CD burning software you should find an option for video CD, which you can add MPEG1 files into. Set top DVD players automatically start playing track one of a video CD, and will skip to the next track when the next button is pressed.
The full DVD format is 720x576 pixels so the picture does look sharper. To make a suitable DVD – without a preset ‘menu’ page - does need authoring software like Adobe Encore – not the cheap bundled software that comes with a DVD writer.
Solid state video
players, running from compact flash card memory are more reliable, and the price
has fallen dramatically. I've now converted my simulators to run off Grandtec's
Eyezup Pro players (£59 from cpc.co.uk). These are simpler than DVD players
because there is no need to author a DVD. The player simply plays MPEG2 tracks
in filename order. Its not perfect though because I have to hack into the eyezup
remote control, which is fiddly and potentially less reliable. I've
recently tested a more industrial video player called a DV68, made by Medeawiz.
(£165 + £35 for a switch keyboard for accessing 8 different tracks). It seems
perfect, I'm going to change all my machines to run on them - both video and
audio.
HD TV is now possible, and its good for arcade machines as people are watching the screen close up. However there are many electronic 'hot spots' which often degrade the image between the camera and the final edited film on HD TV. Buy everything you need at the same time and try it out quickly so you can send it all back if the final image isn't HD quality. I've been waiting until things improved, but I'm thinking of trying it out soon.
Video Monitors
It is not completely straightforward to get a TV set to switch on and find the right channel automatically. Connect the DVD player with a scart lead to AV1 and it should find it automatically. Most TVs switch on to standby mode, so I add a delay timer to the channel+ button, giving it an initial pulse contact.
Computers
I’ve tried incorporating a PC in two coin op machines. In one (the Gene Forecaster), I wired into the mouse button. This simply started a macromedia director movie. This requires a button to be pushed to start up the computer every morning. More recent computers can be set to switch on automatically when the power comes on. The start menu can also be set to launch any program automatically.
In the other machine (my Expressive Photobooth) other I wired external switches to 5 of the keyboard switches. Macros, called actions in photoshop, are then triggered by the keyboard switches. This is a powerful technique which has all sorts of possibilities for making elaborate machines without any programming language skills.
The disadvantages of using computers are that when something does go wrong, there are so many levels of complexity that it’s been very time consuming and expensive tracing faults. Perhaps I should be less pessimistic as neither of the major faults I spent months tracking down were buried too deeply. One was simply caused by inadequate cooling – the computer was inside the machine housing. The other was caused by inadequate shielding round the keyboard interface circuit.