When dealing with arcade monitors, there are a few relatively easy things that you can do to improve the visual quality and prevent a potential monitor catastrophe.  I'll take you through a few easy fixes and show you one or two that require a little more experience.



I recently went to my buddy Lance's house to perform the triple threat on my monitor: cap kit, flyback, and rejuve.  I have one of the most common arcade monitors out there, a Wells Gardner K7000, so finding parts was no problem.  I ordered the monitor repair kit (consisting on a cap kit, HOT (horizontal output transistor), fuse, and flyback), as well as some new buttons and joysticks (foreshadowing!) from therealbobroberts.net.  It never hurts to do a cap kit on a monitor, but the flyback is a slightly stickier situation, so I generally don't replace them unless they are on the way out.

Before you do anything, discharge your monitor to make it safe to work on.  There are a billion YouTube videos that explain the process.

To remove your monitor chassis, you will probably have to cut one or two wires, just give yourself enough room on both sides so you can solder the wires back together again when you are done, or you can just use wire nuts.  I recommend using a label maker so that you know which wires go back together when you are done.

Once you have discharged your monitor and removed the chassis and neckboard, your operating table should look something like this:


To work on your monitor chassis you will need:

- A simple multimeter
- The cap kit for your specific monitor
- A soldering iron and solder
- A small pair of diagonal cutters/dikes
- One of these three items: De-soldering gun (most expensive/easiest), De-soldering pump (cheap and relatively easy to use, or De-soldering braid (cheap, crappy, and you will probably burn your fingers).

In the past, I have always used a De-soldering pump.  It is a spring loaded syringe that sucks in at the push of a button to pull molten solder off of a component. 

My buddy owns a de-soldering gun, so that's what we used. Once you melt the solder with the tip of the gun, you pull the trigger to suck the solder away.  Super dupes easy.


The cap kit process is quite simple.  De-solder and remove a capacitor from the board, check the list that came with your cap kit and replace it with the correct cap.  Make sure you insert the capacitor correctly.  The positive post should be marked on the board and on most caps, the positive leg is longer so you can easily tell which side is + and which is -.  I like to bend the legs of the capacitor outward so it stays in the board and then solder them all at once.


Once all of the new caps are in, it's a good idea to double check them against your master list.  Once you are satisfied, solder away and clip those legs off.  Don't forget that you may have caps on your neck board.  I thought I was finished soldering, but when I did my final inspection...OOPS!... I forgot to solder the neck board cap.



Replacing the flyback transformer is pretty straight forward.  De-solder all of the pins, pull the old flyback out, put the new one in, and re-solder.  In the case of my monitor, there is an aluminum cover/heatsink in the way of my flyback and the HOT is connected to it.  If I weren't replacing the HOT, I would have to de-solder at least one leg so that I don't break the HOT when I pry the cover off.  Since I am replacing the HOT, I just de-soldered the whole thing.  The placement of the HOT differs from monitor to monitor.  It's just 3 posts to de-solder and re-solder, very easy to replace.

There will usually be a small piece of plastic film between the HOT and the heatsink, make sure that you don't lose this.  It prevents the HOT from shorting against the heatsink and needs to be re-installed.

The pins on the bottom of the flyback are never perfectly lined up.  It takes a little practice and you will have to bend one pin at a time so that they fit perfectly through the board.  Once you have it in, you can solder the pins in place.


Once all the wires on the flyback are re-connected to their previous locations and you have given your board a thorough inspection, you are done with the chassis.  If anything looks suspect like a lifted pad, broken trace, severe burn marks, etc., go ahead and set your multimeter to continuity mode to make sure all of your connections are good before calling it a day.  It's also a good idea for older monitors to "re-flow" some solder points that don't look very good.  Fresh solder can do wonders on old joints.

OK, so, I know I told you that we would be doing a rejuve on my tube, but I decided not to do it.

What is a rejuve?  Over time, elements inside the tube can acquire buildup that can make colors seem faded, washed out, and just plain bland.  A tube rejuvenator applies voltage to the guns of the tube to burn this buildup off and results in a better picture.  Once we removed the monitor frame, we found a sticker that said the tube had already been rejuvenated in 2008.  Since a rejuve slightly shortens the lifespan of a tube, I decided that I would rather not risk it for a monitor that looked fine before we started this process.

So, here is my monitor frame sans chassis/neck board:


And here is the finished product


The monitor will definitely need to be adjusted after this process.  It's a good idea to turn the color adjustment dials on your monitor and neck board to neutral positions.  I'd also turn down the screen pot on the flyback down pretty low.  When the monitor boots up, turn up the screen knob until the picture is visible, but not too bright. Then, adjust the focus knob until the image is sharp.  Once the picture is sharp and your screen setting is bright enough, but not too bright, mess around with your colors until you reach your desired result.  It may need some tweaking, but here is where I am after my initial adjustment:


The next article will be dedicated to the control panel.  Instead of modifying the original panel, which I want to keep as original as possible, I'm building a new panel from scratch, complete with artwork.

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