Many of the questions that we receive involve arcade games that are playing blind. Playing blind refers to a particular troubleshooting symptom where you can hear sound coming from the game but the screen does not show a picture. While playing blind can be related to power or board problems, the monitor chassis is most often the culprit when trying to repair this issue. In this post, we’ll discuss some basic and advanced techniques that will help you troubleshoot and repair arcade games that are playing blind.

Troubleshooting Games That Are Playing Blind

http://www.youtube.com/watch?v=ODEYZIzkSXk

Before we get specifically into playing blind issues, let’s talk about some general arcade troubleshooting for “dead” games. After all, your arcade game may be playing blind and you might not know it. First off, try powering on your arcade game and pressing the start button. If you still don’t get any sound from your game, you might try coining it up and then pressing the start button. After you have determined that you’re game is playing blind, try turning up the brightness and the contrast to see if it makes a difference in your screen. Your screen could just be too dark for you to see. If adjusting the monitor doesn’t make a difference then we’re probably having some monitor related issues.

Let’s start our monitor troubleshooting by checking the power wires. There should be a 2 or 3 prong Molex connector with wires going through it that go from the bottom of the cabinet to the monitor chassis. These wires could be coming from an isolation transformer (looks like a brick in the bottom of your cabinet) or directly from the AC line. Using a multimeter, located the two AC wires and measure the voltage coming off of them at the Molex connector. We recommened measuring the voltage from the monitor side of the connector to make sure power is getting all the way through. If you do not get any AC voltage reading, check to make sure there is not a blown fuse or bad wiring in the bottom of the cabinet. Otherwise we can move on to checking the video wires. Make sure that these wires are making a good connection from the game board to the monitor chassis. Also, the pins on the monitor chassis where the video connector makes contact can become loose. Try resoldering these pins if they do not feel secure.

With most of the basic monitor troubleshooting out of the way, we can move on to the more advanced problem areas. With the game on, look at the neck of your monitor to see if there is any glow. This neck glow usually indicates that your monitor chassis is getting the high voltage it needs to display a picture. If this glow is missing, you probably need to start looking at the power supply section of your monitor chassis. Start out by looking for any fuses on the chassis that might be blown. Once you locate one, try to replace it with the correct fuse. Some monitors have a label on the chassis to indicate the type of fuse required. If your monitor does not indicate what fuse to use, try getting one similar to the one currently on the chassis. With the new fuse in place, try powering on the game again to see if the fuse blows. If the replacement fuse blows then we might be having an issue with our Horizontal Output Transistor (or HOT) or some of the diodes on the board.

For more information about diodes, check out our post on Checking Diodes On An Arcade Monitor. In this post, we discuss how to check the diodes on your chassis that might be causing your fuse to blow. Once you have checked your diodes and replaced them as needed, try checking your Horizontal Output Transistor (or HOT) to see if it is functioning properly. On our Volume 2 DVD, we have a video on Checking The Horizontal Output Transistor that shows you how to use a multimeter to check your HOT. We recommend purchasing this DVD if you are not already familiar with this process. With the diodes checked and the HOT replaced, try powering on your arcade game again to see if the issue is resolved.

You might notice in our video for this post that checking the diodes and replacing the HOT did not repair our issue and actually led to some electric discharge known as arcing. Arcing is usually an indicator of a bad flyback. The flyback (along with the suction cup or anode) is the part that supplies power to your monitor tube. As you might expect, it contains quite a bit of high voltage and can be quite dangerous if you do not use caution. Make sure to take all necessary precautions to protect yourself against electric shock. If you do experience arcing, immediately unplug the game. Since you have pretty much determined at this point that the flyback is bad, remove your monitor chassis and replace it. Our Volume 2 DVD also has a video on Checking And Replacing The Flyback that shows you how to check to see if the flyback is good and how to remove and install it. We recommend purchasing this DVD if you are not already familiar with this process.

Please note that every arcade monitor is different. Even though these steps helped us repair our monitor, there might be some additional steps that need to be taken in order to repair your specific make and model of arcade monitor. Consult your monitor manufacturer and their documentation for any additional information or steps that need to be taken. The monitor featured in our video for this post is a Wells Gardner K7000 Series.

Arcade games that are playing blind account for a large amount of the questions that we receive. Now that you know a little bit more about how to troubleshoot and repair this issue, you can conquer one of the most common problems that plagues non-working arcade games. Please leave any questions or suggestions in the comments section below.

While playing your arcade game, you might notice the colors on your monitor fading over time. We would normally discuss installing a cap kit as one of the possible solutions for this issue. With that said, what happens if you do the cap kit and the colors on your monitor still don’t looks as rich as they did before? In this case, your monitor might be a good candidate for a tube rejuvenation. In this post, we’ll discuss how to rejuvenate your tube in order to restore the picture quality of your arcade monitor.

Using A Tube Rejuvenator

http://www.youtube.com/watch?v=_kgy7CCsEBQ

Full post coming soon.

If you’ve worked with arcade games for any length of time, you’ve probably come across your fair share of monitor issues. One of the more common problems we see with arcade monitors is known as screen collapse. In this post, we will discuss how to repair monitors that are experiencing screen collapse issues.

Repairing Monitor Collapse Issues

http://www.youtube.com/watch?v=Sz28ATC-PE8

Let’s start our troubleshooting by determining what kind of collapse we have. It’s important to note that screen collapse can happen in varying degrees. You could have a partial collapse where you can still see some of the screen or a complete collapse where the entire screen has been condensed into one thin line. Monitors can collapse either vertically or horizontally. The orientation of the collapse is based on where the anode (or suction cup) is located on the tube in relation to the collapse. If the collapse runs parallel with the anode, you are experiencing a vertical collapse. Otherwise you are probably experiencing a horizontal collapse.

Many people tend to mistake vertical collapse for horizontal and vice versa. In order to help you identify the difference between the two, we have posted the picture below. This picture illustrates vertical collapse on both a horizontally mounted monitor and a vertically mounted monitor. Also, keep in mind that Installing A Cap Kit first might solve your problem if you’re only experiencing partial collapse.

Click Image To See A Larger Version

Once you have identified the type of collapse you are experiencing, you can begin the process of repairing your monitor. We will mainly focus on vertical collapse since it is more common of the two types. Vertical collapse usually occurs when the parts in the vertical section of your monitor chassis fail. One of the primary parts that’s located in this section is the vertical IC (or Integrated Circuit) chip. This chip is usually attached to a heat sink which looks like metal railing protruding from the monitor chassis. If you’re having trouble locating the vertical IC chip or the vertical section as a whole, you can follow the yellow and green yoke wires to where they connect on the chassis. Keep in mind that sometimes the yellow and green wires will come into one part of the chassis and will have traces that connect them to the vertical section.

Click Image To See A Larger Version

Before you suspect your vertical IC chip of being bad, you might take a look at the rest of the parts in the vertical section. Often times manufacturers will assign similar numbers to parts that are in the same section. An example of this would be the Electrohome G07 monitor chassis which labels all of the parts in the vertical section starting with the number 400. Look for broken or cracked solder joints around the parts in this section. You can also check these parts with your multimeter to make sure they are working. These are some good steps to take before suspecting the vertical IC chip of being bad.

If you check the parts around your vertical section and your monitor is still not working properly then you probably need to replace the vertical IC chip itself. These chips come in several different configurations. The most common style of chip in arcade monitors is the “small” style which looks like a standard transistor with more legs. If you need help identifying which chip to order, you can use the NTE Electronics Cross Reference page to put in the number that’s currently on the chip and get the NTE part number of the chip that you will need to order as a replacement.

Even though most monitor issues can be traced back to the chassis, there may be some instances where the tube is at fault. Missing colors, color smearing or screen blurring are just some of the symptoms that might indicate a bad monitor tube. In this post, we will discuss how check a monitor tube and troubleshoot other monitor color issues.

Checking A Monitor Tube

http://www.youtube.com/watch?v=lKOK6QB9frM

First off, let’s discuss some of the different symptoms you might be experiencing if you have a bad tube. The most common symptoms of a bad tube are missing colors, color smearing or streaking, convergence issues and/or screen blurring (especially in the corners). Keep in mind that in some of these cases you might be able to do some minor tweaks to fix the issues. If your screen is out of convergence, you might take a look at our post on Adjusting The Convergence Rings before suspecting your tube. The same goes for color issues as Adjusting An Arcade Monitor might help fix them without the need to test the tube. Since the tube is usually not the problem, make sure that you’ve exhausted some of your other resources before putting the blame on it.

Once you have exhausted some of the more common chassis repairs, we can move on to testing the tube. Before we begin the process, you will need a wire with alligator clips on each end. You can either make one your self (which is a similar process to what we talk about in our post on Safely Discharging An Arcade Monitor) or you can purchase one from your local electronics store. It is also a good idea to have a mirror positioned so that you can see the screen or a friend that can tell you what’s going on while you are doing this process.

Buy a Alligator Clip Set (10 Pc) from Amazon.com now!

Now that we have our wire with alligator clips on the ends, we can test our tube. Take the back door off of your game so that you can gain access to the back of the monitor. Clip one alligator clip to a ground on your monitor (such as the frame). Look at the back of your monitor’s neck board and identify which of the circular points control the colors. Most of the times these are labeled to make it easy for you. When you have identified the color pins, quickly touch the non-clipped end of wire to the pins and see what happens on the screen. Be careful not to hold the end of the wire on the pins for too long. When you do this, you should get a bright screen just featuring the color pin that you touched and some retrace lines. If this does not happen then it could mean that the tube is bad and needs to be replaced.

Let’s say that your tube is good but you are still having some missing color issues. It could be that some of the parts on the neck board are malfunctioning. There should be a transistor and a resistor located on your neck board that drive each of the primary colors. You can check the transistors by removing them from the neck board, setting your multimeter on continuity (or diode) test and checking the continuity between the pins. If you do not get continuity then you probably need to replace your transistor.

Resistors can also be tested with a multimeter but the process is a bit different. Instead of using the continuity (or diode) test, you will need to set your multimeter on Ohms (or Ω). When you put your probes on the leads you should get a reading on your multimeter. If the resistor is good then this reading will be pretty close to the value indicated by the color bands. The Resistor Reader page on Bob Roberts site can help you identify this value. There are also charts that you can buy that will tell you the values of each color band as well.

While many people like to suspect the tube whenever they have monitor issues, this is often not the case. Being able to identify and test a bad tube will save you a lot of time when troubleshooting monitor problems. Please leave any questions or suggestions you have in the comments section below.

As we’ve talked about in our previous posts, most arcade monitors can be fixed just by repairing the chassis; however, there are some instances where you need to replace the monitor in your arcade game entirely. Cracked neck and screen burn are just some of the reasons that might lead you to consider this option. While doing this is more tedious than just removing and installing the chassis, it can be accomplished with just a few simple steps. In this post, we are going to discuss how to remove your current arcade monitor and install another one in it’s place.

Replacing An Arcade Monitor (Part One)

http://www.youtube.com/watch?v=-yyTaoAtWe8

Replacing An Arcade Monitor (Part Two)

http://www.youtube.com/watch?v=VG_9RuJ9xi8

As we’ve talked about in previous posts, monitors hold an extremely high amount of voltage which can be very dangerous to you should you come in contact with it. We recommend unplugging or turning off the power to your arcade game before attempting any of the steps below. Always be safe and take the time to make sure that your arcade game is unplugged when working with the monitor. Once we have unplugged the arcade game, we are going to discharge the monitor so that we can safely remove it from the cabinet. Please see our post on how to Safely Discharge An Arcade Monitor for more information.

Just like in our post on Removing And Installing A Monitor Chassis, the first thing we are going to do is disconnect the power wires going to the monitor. Most games use a Molex connector between the power supply and the monitor chassis which allows for a clean and easy disconnect. If your monitor chassis doesn’t have this Molex connector, you might need to cut the wires in order to remove the monitor. If you end up cutting the wires, you might consider installing a Molex connector to make it easier on you in the future. Please see our post on Installing A Molex Connector for more information.

With the power wires disconnected, we are now going to look for the video wires coming from the board. If you examine your wiring harness coming from your board connector, you should see a set of about 5-6 wires that connect directly to your monitor chassis via a Molex connector (or connectors as sometimes there are more than one). These wires control the video output coming from the board to the monitor. In order to get the monitor out safely, we must disconnect these wires from the monitor chassis. Make sure that you note or create a diagram of which wires go to which pins on the chassis as it will come in handy later once we have installed the other monitor. Once you have made that notation, you can remove these wires which should free your monitor from all cabinet wiring.

Now that the monitor is discharged and all cabinet wiring is disconnected, we can now safely remove our monitor from our arcade cabinet. Most monitors come out of the front of the arcade cabinet so you will probably need to unlatch your control panel and remove your bezel as well as any other obstructions that might block the monitor from coming out. Once we have removed these items, you should notice some sets of screws or bolts at the corners of the tube. One set holds the tube to the frame and the other set holds the frame to the cabinet. Most of the time we will want to remove the screws or bolts that are holding the frame to the cabinet so that we can remove the entire monitor and not just the tube. Please see the image below for more information.

Once we have removed the bolts or screws that are holding the frame to the arcade cabinet, we can proceed with removing the monitor. As we talk about in the video, this is a great two person job especially if you are working with monitors that are larger than 19 inches. Position one person in the front of the cabinet and the other in the back. Have the person in the back lean the top of the monitor frame forward while the person in the front attempts to catch it. When the top of the monitor is being held in place by the person in the front, the person in the back can come around to the front and grab one side while the other person rotates around to the other side. Once you have both established a firm grip, lift the monitor up and out of the cabinet. We recommend setting the monitor down on the part of the frame that supports the monitor chassis. If you plan on laying the monitor on the face of the tube, make sure that you have something soft to lay it on such as a blanket or a piece of cardboard to prevent scratches.

Before we begin the process of installing our other monitor, we recommend doing a couple of checks just to make sure that the monitor we are installing is going to work in our cabinet. The first thing you want to check is to see if the frame of the monitor your installing is similar to the monitor you just removed. If they are not the same, you might have to transfer the chassis and tube from the frame of the monitor you are installing to the frame of your old monitor. This is not a difficult process but it can be somewhat tedious. The second thing you want to check is that the monitors are roughly the same size. Take the length and width measurements of the monitor frame you are going to install to see if they are comparable to the monitor you are replacing. While you are taking these measurements, you might also check the viewable size of your monitor by measuring diagonally across your monitor from the inside black line. Please see the image below for more information.

Now that we’ve determined that our monitor is compatible with our cabinet, we can begin the process of installing it. We’re going to use the same process as we did when we removed the old monitor from the cabinet except in reverse. Start off with one person holding each side of the monitor. Gently lift up and place the bottom of the monitor into the cabinet. One person rotates from the side to the top of the monitor while the other person runs around to the back of the cabinet. Once the back person is in position, the front person can lean the top of the monitor into the cabinet with the back person making sure that the monitor is positioned correctly and free from obstructions. When the monitor is in place, we can then screw or bolt the frame to the cabinet to keep it from shifting when we’re moving it. At this point we should have the monitor secured to the cabinet and are now ready to wire it to our harness.

In a perfect world, all of the power and video connectors that every arcade game uses would be the same and we wouldn’t have to do any conversion to get it to work. Unfortunately this is not always the case. In order to get your newly installed monitor to work in your cabinet, you need to determine what kind of connectors it uses for video and power and see if they are the same as the connectors in your cabinet. If they are not the same, you might need to do some rewiring or repinning to get them to work. If you have the video connector for the new monitor, you can always tie the wires from your cabinet harness to this connector wiring provided that you can figure out which wire goes where. Make sure you refer to the diagram that you made for the connectors on your old monitor to give you a better idea. Of course, power is a little simpler as it is only 2-3 wires which can be easily identified using a multimeter. You can also use wire nuts on these wires if you are not experienced with or do not have any Molex connectors.

If you are having trouble figuring out the wiring for your newly installed monitor, here are some tips that might help you out. You might find that the newly installed monitor has a place for two sync wires but you only have one coming from your harness or vice versa. You might have to split or combine these sync wires depending on the requirements of the monitor. This can be accomplished quite simply by stripping the wire a couple of inches above the end and either tying or combining another wire into it at this point depending on the circumstance. If you’re having trouble figuring out which video wires are performing what functions, see if you can get a copy of the manual for your game board. The manual should contain the pinouts which you can then follow from the harness to determine the function of each wire.

Once we have finished wiring up the power and the video, we are now ready to try out our monitor. When we turn on the monitor for the first time, we might notice that the screen is not quite right. A lot of times you will need to adjust the monitor in order to get the desired picture. Please see our post on Adjusting An Arcade Monitor for more information. If you are still having trouble getting the picture the way you want it, you might check your wiring to make sure everything is correct. It could be that you have incorrectly hooked up your sync wires. Below are some pictures of what an out of sync screen looks like compared to a screen that just needs some hold adjustment to give you an idea of the difference. Hopefully after some minor wiring and potentiometer adjustments you can get the picture to the way that you like it.

Click Image To See A Larger Version

Although repairing the chassis will fix the majority of monitor issues, there are just some problems that require a complete monitor replacement. Knowing how to replace a monitor will be a very useful skill for those times when a chassis repair just won’t get the job done. Please feel free to leave any questions or suggestions in the comments section below.

Most of the time when we hear symptoms such as color bleeding or shadowing, our first thought might be to install a cap kit. While cap kits are known to solve problems such as these, it could just be that our convergence rings are out of alignment and need to be adjusted to correct the picture. In this post, we will discuss how to adjust the convergence rings on your monitor so that you can correct these type of symptoms as well as other convergence issues.

Adjusting The Convergence Rings

http://www.youtube.com/watch?v=eDuKddayX-E

Before we begin adjusting our convergence rings, it is important to note that the monitor must be on during the adjustment of these rings if you want to be able to see happening on the screen. With that said, make sure that you take the necessary safety precautions to keep yourself from getting shocked during the process. As we talked about in our post on Adjusting An Arcade Monitor, we would highly recommend either getting a friend or a mirror to help you with the adjustments. This makes it much easier to know what’s going on with the screen when you are making adjustments to the rings.

Our first step is to locate the convergence rings on our monitor tube. If you are looking into the back of your arcade cabinet, you may notice several sets of rings wrapped around the neck of the monitor tube. These are what we like to call the convergence rings. You might also hear them referred to as the purity rings as well. These rings are magnetized allowing them to direct the CRT electron beams to the desired locations on the screen. Before we actually turn the rings for the first time, it is a good idea to take either a lightly-colored paint pen or some correctional fluid and draw a line across the rings so that you know what your starting point is. You might also have a different color of pen or fluid handy to mark across the rings again once you have found the correct position for them.

Once we have made the mark across the convergence rings on our monitor tube, we can begin adjusting them. If your PCB has a video test mode for convergence available, we would recommend putting the game in that mode so you can easily tell when the convergence is correct. Watch the screen as you slowly turn each ring until you feel that the picture is correct. When you have adjusted the convergence rings to your liking, you can mark across them with the other pen or fluid that we mentioned above. If you don’t plan on making any more adjustments on the rings, you can also take some glue and apply it across the rings to hold the adjustments into place for years to come.

Color bleeding and shadowing is a pretty common problem with arcade monitors in general. Before you decide to install a cap kit on your next monitor with these issues, you may try adjusting the convergence rings as the starting point for your repair. If you have any other comments, questions or suggestions about adjusting the convergence rings, feel free to leave a message in our comments section below.

If you’ve worked on many arcade games, you might have come across a problem where your picture does not fill up the entirety of your screen even after you’ve tried multiple potentiometer adjustments. It could be that this problem is related to a part on your monitor chassis called the horizontal width coil. In this post, we will discuss how to adjust the horizontal width coil so that the picture fills your screen on your arcade monitor.

Adjusting The Horizontal Width Coil

http://www.youtube.com/watch?v=QuTlChCko4k

Before you begin, we highly recommend purchasing a plastic or non-conductive alignment tool kit. These kits come with plastic tools that are specifically used to adjust these kinds of parts. You can use an Allen wrench to adjust the horizontal width coil, however, there are many down sides to doing this. For one, an Allen wrench generates a lot of torque that could cause your coil to crack or break. Also, you must have the game off while you are using the Allen wrench to adjust the coil. If the game is on when doing this the Allen wrench will heat up and can burn your hands not to mention that you will be navigating around some very high voltage areas with a piece of metal in your hand. Take our recommendation and purchase a plastic or non-conductive alignment tool kit.

Buy the Non-Conductive Alignment Tool Set, 5 Pc. from Amazon.com now!

Buy the Universal Color TV Alignment Tool Kit from HAPP Controls now!

Please make sure to be careful around your chassis if you are attempting to adjust the coil while the game is on. Should you make contact with any high voltage areas on your chassis you could receive a bad shock. Be very cautious at all times when attempting this process. Also, it’s a good idea to set up a mirror in a position where you can the results that are caused from your adjustment.

Now that you have the correct tools and setup, it is time to adjust the horizontal width coil. Take your alignment tool and carefully place it into the coil and attempt to turn it. You may need to turn it clockwise and counter-clockwise a couple of times to loosen it up. Try not to force it too hard as too much torque even with the alignment tool can break your coil. If you cannot get it to turn or do not see a change in your monitor you might try leaving the monitor on for about an hour and retrying this process. This should cause the coil to heat up making it more easy to adjust.

If you have tried the techniques we’ve mentioned and you still do not see the changes you want, you could have more of a capacitor problem than a horizontal width coil problem. Look around your coil and see if you can find any polypropylene capacitors. These capacitors typically look like rather large pieces of Chiclets chewing gum and also control the picture width. Try replacing these capacitors to see if it changes your picture. You could also try checking your B+ voltage adjustment on your chassis. If the value of it is incorrect (it should be 120 VDC on most monitors) then this could also cause some picture size issues.

A Polypropylene Capacitor

Buy a Monitor Width Cap Kit from Bob Roberts now!

If you deal with enough arcade games you will eventually come across this problem where the picture does not fill up the entirety of your screen. Knowing how to adjust the horizontal width coil as well as the other measures we described should help you greatly in solving these issues in the future. As always, please leave any questions or suggestions in the comments section below.

The majority of problems you will encounter with arcade monitors will involve working with the monitor chassis. In order to properly work on or repair a monitor chassis, we must be able to remove it from our arcade cabinet. In this post, we will discuss how to remove and install a monitor chassis from an arcade monitor so that we can make any necessary repairs to it.

Removing And Installing A Monitor Chassis

http://www.youtube.com/watch?v=BNnbEPY7DVM

Before you begin, we recommend unplugging or turning off the power to your arcade game. As we’ve talked about in previous posts, monitors hold an extremely high amount of voltage which can be very dangerous to you should you come in contact with it. Always be safe and take the time to make sure that your arcade game is unplugged when working with the monitor.

On that same note, the first thing we are going to do when attempting to remove a monitor chassis is to disconnect the power wires going to it. Most games use a Molex connector between the power supply and the monitor chassis which allows for a clean and easy disconnect. If your monitor chassis doesn’t have this Molex connector, you might need to cut the wires in order to remove the chassis. If you end up cutting the wires, you might consider installing a Molex connector to make it easier on you in the future. Please see our post on Installing A Molex Connector for more information.

Once we have disconnected power from the arcade monitor, we can remove the anode cup from the tube. Removing the anode cup is very similar to discharging the monitor. The main difference is that instead of just sticking the screwdriver up underneath the anode cup and waiting for a pop, we are going to use the screwdriver to push the prongs of the anode cup together so that we can remove it from the tube. For more information on this please see our post on how to Safely Discharge An Arcade Monitor.

Now that we have removed the anode cup from the tube, we can move on to unplugging the neck board. The neck board is connected to the very back end of the tube. It is usually a square circuit board and has wires connected from it to the main chassis. It might also have a ground wire attached to it from the monitor tube. If it does, make sure that you cut or unplug this wire before trying to remove it. The neck board should come off pretty easy with just a light amount of force. Sometimes you might find that someone used silicon or another adhesive to keep the neck board in place. It is best to remove this before trying to remove the neck board.

With the neck board unplugged, we can now locate and unplug the degaussing coil and yoke wires from the monitor chassis. The degaussing coil runs around the monitor tube and plugs into the monitor chassis via a two prong connector. The yoke wires come off the monitor tube and attach to the chassis via a four prong connector. The connector for the yoke wires is usually keyed with a wider space between one of the outside pins and the rest to make it easy to hook up. If your monitor chassis has two places where the yoke wires can plug in, make sure to remember which set of pins you removed it from. Locate and unplug both sets of connectors.

Next, we are going to located and detach the video wires coming from the board or PCB. These wires are responsible for making sure that your monitor gets the image the board is sending it. Sometime these wires might be split into multiple connectors. Make sure that you notice how these connectors are plugged in before attempting to remove them. Locate this connector and remove it from your chassis.

After all of these steps have been completed, you should be able to unscrew the chassis from the mounting bracket and remove it from your arcade cabinet. If your ground wire was not attached to your neck board like we talked about earlier, make sure that you detach it from the chassis before attempting removal. With your chassis removed, you can now take steps to repair it or send it off.

Installing the chassis back into your arcade cabinet is as easy as doing these steps in reverse. One item to note is that your neck board is keyed and only goes one way. Make sure that you look at both the back of the tube and the neck board so that you can line them up correctly to each other. If you have any questions or suggestions about this post, please leave them in the comments section below.

Sometimes when you move a game you might find that your monitor has some areas of discoloration or that your once bright colors now appear somewhat washed out. This might be due in part to some unwanted magnetic fields interfering with your screen. In this post, we’ll discuss how to use a degaussing coil to solve the issues caused by these fields.

Using A Degaussing Coil

http://www.youtube.com/watch?v=xboO2JUvtBM

Before we get started, let’s talk about what a degaussing coil does. The job of the degaussing coil is to demagnetize the shadow mask which is similar to a metal mesh plate located inside your tube. The holes in this plate are aligned to ensure that the electrons from the red, green and blue cathode guns reach the same colored phosphors on the monitor. Should this plate become magnetized, the color and focus of your screen can suffer. Hopefully by demagnetizing the shadow mask you can solve some of the discoloration and focus problems you might be having. Please see our links below for more information on purchasing a degaussing coil.

Buy a Degaussing Coil (CRTs Less Than 19″) from MCM Electronics now!

Buy a Degaussing Coil 13″ Pro from Bob Roberts now!

Once you have purchased a degaussing coil, you can begin the process of degaussing your monitor. First off, make sure that you have the degaussing coil plugged in and that the power to your arcade game is on. Take the degaussing coil and hold it to the center of your monitor screen. Press the button to active the degaussing coil and move it in small circles across the front of your monitor. Slowly begin to widen the circles as you back away from the monitor. As you do this you will notice the degaussing effect on the monitor start to dwindle. Keep repeating the circles until the coil has no effect on the monitor then release the button. You have now completed the process of degaussing your monitor.

At this point, you might want to check your screen to see if it made a difference in your picture. We sometimes repeat this process if we didn’t get the desired effect the first time. Remember that this process can be used for any CRT based screen not just arcade monitors. If you have any comments, questions or suggestions about degaussing a monitor please leave them below.

When a monitor just has a black screen, it’s a pretty good indication that it’s not getting power. The typical places to start with this kind of issue would be the power cord and the HOT, but lets say that you’ve checked them and they are not your problem. Where do you go from here? In this post, we will discuss how to check diodes on your monitor chassis to make sure that they are in working order.

Checking Diodes On An Arcade Monitor

http://www.youtube.com/watch?v=u4l-kosl0vg

The diodes we are talking about are located in the power supply section of your monitor chassis. There are usually about 4 or so located right in a row in this section. Examine your monitor chassis and see if you can find them. In the video, ours were located near a large capacitor. Once you have located these diodes, you can check to see if they are shorted or not.

Before we begin, you might want to refer back to our post on Checking Fuses With A Multimeter to get familiar with the diode test settings on a multimeter.

The process of checking a diode is very similar to checking a fuse except that the indicators are reversed. When we checked fuses, we wanted our meter to generate a long beeping sound or a 0 (ZERO) ohm reading. If our meter reads this while we are checking a diode, this indicates that it is shorted and is not working properly. Shorted diodes can be caused by many things including hooking up power to an arcade monitor that requires an isolation transformer. Always be sure that you are using an isolation transformer on monitors that require it.

If you find a shorted diode, you need to replace it. Desolder it from your board using your desoldering iron or solder wick and solder the new one into place. Always make sure that you replace the shorted diode with another one that has the stripes oriented exactly like the original diode. Also, be sure that all of your power wiring to your monitor is correct before turning it back on. Doing this will save you from damaging another diode and having to repeat this process over again. Once you have replaced these shorted diodes you are finished with this part of your repair.

Sometimes a black monitor screen can mean more than just a power cord or HOT issue. Knowing to check your diodes before moving on to more complex repairs can save you lots of time and effort. Please feel free to leave any questions or suggestions in the comments section below.