Troubleshooting board (or PCB) issues might just be the toughest part of arcade repair. While many board repairs require sophisticated equipment, there are some simple things you can check before sending your board off to a qualified professional. In this post, we will discuss how to inspect and identify problems with an arcade board before you send it off for repair.
Inspecting An Arcade Board
Let’s talk about some of the tools you’ll need to do your arcade board inspection. It’s good to have some type of magnification device. It could be a magnifying glass, a magnifying visor or a magnifying lamp. Looking through a magnification device will help you identify small issues such as broken solder joints on the board. A small screwdriver (such as our recommended Suzo-Happ Screwdriver) or chip extractor to help with removing chips from the board. A machinist scribe for etching oxidation off of chips. A razor blade kit to scrape away parts of the board for testing. Small needle nose pliers and nippy cutters for holding parts or cutting wires. A brush set and canned air to clean the board and other parts. Of course, it’s also a good idea to keep around Your First Arcade Toolbox as it contains many of the tools you’ll need for this project.
Just as a quick note, we want to be careful that we don’t build up static electricity as this can harm the board. We recommend using some sort of anti-static wrist strap or gloves to prevent you from accidentally doing damage your board.
Let’s begin our board inspection process by cleaning the board. Start off by using the canned air to blow any dust, dirt or debris off of the board. If you have access to an electric duster, feel free to use it instead of the canned air. Follow up the canned air with the brushes to help remove some of the more caked on dirt from the board. We recommend following up the brushes with another round of canned air to remove any dust that might have come loose during the brushing process.
Now that our board is clean, we can begin the inspection process. We like to start off at the harness connector. Use the magnifying glass to look for any broken parts on the connector. Remember that the game receives it’s power and control inputs through this connector. Feel free to use a multimeter at this point to make sure that power is going from the pins on the connector to the next part on the board. Once you have inspected the connector, you can clean it by using the eraser end of a standard pencil. Make sure that you clean both sides of this connector. This will help remove any built up dirt that has gathered on the connector pins.
You might notice that your board has several different types of chips on it. Some of these chips may be socketed and some may be soldered directly to the board. If a chip is socketed, it’s a good indication that the manufacturer thought that the chip might fail at some point. You can remove these chips pretty easily by using a small flathead screwdriver or a chip extractor tool. Be very careful not to pull the chip out too hard as you can break the legs if you’re not careful. Gently pull up on each side going back and forth until the chip is removed. With the chip removed, you can use the machinist scribe to etch off some of the oxidation that has built up on the chip’s legs. You can also use your brush set to clean the legs as well as the sockets themselves.
Just like we talk about in our post on Installing A Cap Kit, there might be some capacitors on your board that are bad. A bad electrolytic capacitor will often swell or bulge at the top or leak out of the bottom, however, they can still be bad even if they don’t look bad. If you have an ESR (Equivalent Series Resistance) meter you can test the cap before you remove it to see if it’s bad or not. Make sure you go through your entire board and replace any capacitors you suspect are bad.
Once we’ve inspected the parts side of the board, we can move on to the solder side. Using your magnifying glass again, look for any broken or cracked solder joints and touch them up as necessary. You also want to look for any scratches that might be preventing electricity (or data) from getting to other parts of the board. In other words, look for scratches that are going through traces. You can test to see if the scratch is preventing the flow of electricity by setting your multimeter on continuity (or diode) test and checking the continuity between the two points. If there is no continuity between the two points then you will need to repair the trace.
In order to repair a cut trace, you will need your soldering iron, some solder and some wire. We recommend using 30-gauge insulated wrapping wire which should be available at your local electronics store. First, cut a piece of the wire that’s a little longer than the trace. It’s always good to have a longer piece of wire in case the wire comes detached from the via (or solder point) and you have to solder it back. Second, strip both ends of the wire leaving just enough for it to make contact with the board. Third, solder the ends of the wire to the board to make up for the broken trace. If you can solder to a via that is preferred, however, you might have to solder directly to a chip pin depending on where the scratch is located. Once you have soldered the wire, you can use some hot glue, electrical tape or another adhesive to keep the wire in place against the board.
Inspecting an arcade board can save you some time and money. Knowing how to identify and fix these types of small issues can keep you from having to send your board off to someone for repair. Please leave any questions or suggestions you have in the comments section below.