Just some tips if you want to repair/clean handhelds:
Opening the gameGadgets from the eighties are wonderful to open and repair. A few things to pay attention to:
- Never use electric screwdrivers. The plastic is very sensitive so use a manual screwdriver all the time. Screws go easy in when closing the game. If they don't screw in easy, stop, rewind and try again. If you have to work hard, you loosen the fit. Only the last turn you should feel it tightens.
- Check the screws. Most companies where smart enough to use the same screws throughout the whole game, but sometimes there are length differences. Very bad to crack your shell because of this!
- Pay attention to button, joystick assemblies. They are often a stack of plastic parts and sometimes a spring. Putting the game together is best done upside-down so all buttons stay in place.
Hard to open gamesMost games are easy to open. 2 exceptions so far:
Coleco tabletops and Entex tabletops.
- The problem with the Coleco is 2 screws are under the CP overlay. You can pull it up carefully, but don't do this too often. I found a solution to make opening the next time easier. If you have it appart, you will see 2 clips at the back of the bottom part. They have a extension on the inside that is not really needed, and if you file it of, you can open the game over and over again while leaving the CPO in place. The part you file off is invisible from the outside.
- The Entex tabletops have screws under the marquee. Same story: don't open unless absolute necessary. You can get it off in neat condition, but don't repeat too often!
No SoundA common problem is these game have lost their sound. 99% chance the contact to the disc-speaker is loose. They are really hard to solder back onto the ceramic, so best option is to buy a new one. All I repaired were 27mm, even today a common size. You can order them here:
http://nl.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=238-022You have to get it out of its shell, but that is easy.
Nothing works at allMost of the time this is just a problem in the internal power cables or battery contacts. Check the electric paths on conductance and if you get power behind the power switch, most of the time the game will work again.
If it is still dead, the problem can be that someone used a wrong AC adapter. This usually blows any of the transistors just after the power switch.
Control malfunctionMost of the time this means dirt under the button contacts. Open the game, remove the rubber strips with contact points, and clean both sides: the PCB contact and the black thingie in the rubber.
Dirt- Use a soft cloth with water to clean the plastic.
- Use a toothbrush for cleaning ridges and embossed letters. Best is the softer pink or blue tip on modern dual action ones. If you manage to get parts completely loose, do the toothbrush part under a running water tap.
- Take apart for best cleaning
- Yellowing can be removed with Retrobright, but I have not tried it myself
- Use your luxury-bathrobe for polishing screens. I found this the best solution! A bathrobe makes very nice shine, yet it does not damage screen print on the transparent parts.
- Sometimes the joystick has a little screw in to hold the ball on top. Mostly it is rusty. Often it can be exchanged with a shiny screw that holds the PCB inside.
