This week I did a few minor repairs to my Frogger while I was on vacation. I had a few parts I recently purchased from Bob Roberts to install, so I took a few hours this week to get some stuff accomplished. First, I needed to install a cap kit. The monitor picture was fuzzy and lacked some clarity. I like to install cap kits for the monitor of any new game I get. It helps to improve the picture and freshen up the image. It’s also really cheap to do! Turns out that I did not buy the right kit. I picked up a kit for a 20″ Sega monitor, which is what I thought this was. Turns out the monitor is even older than the one I thought I had. I spent a couple hours listing out all the caps on the monitor, and turns out I had enough with the kit I bought, plus a few other spares, to replace all of them but five. I’ll pick those up from Bob later on. I took a few pictures and documented the caps I did replace, and sent them to Bob in case he needed them.

After installing the cap kit, I replaced the broken Degauss button inside the coin door. Bob had a full switch panel that he sent me, so I pulled off the nice volume knob and the degauss switch and installed them on the switch panel in my Frogger. They worked great!

Finally, I’ve been really bothered by how back the monitor looks inside the game because I am missing the cardboard artwork bezel. I eventually would like to pick up a new one from Arcadeshop, but until I have the money to do so I thought I would make one from a couple pieces of black posterboard. I reviewed pictures of the original Frogger bezel that I don’t have, and figured I could make one very similar. The bezel lays over the monitor, and has some support pieces underneath to hold it flat and tight to the curve of the monitor. The top of the bezel angles upward, and covers about a 7″ vertical gap against the back door of the cabinet. The real one looks really nice in photos I’ve seen, but I just want to hide the monitor and frame.
I spent a couple hours measuring and cutting posterboard, then I glued all the pieces together. I used some masking tape on the backside of all the glued joints to hold them in place while they dried, and as extra reinforcement.

Here are the results:

Completed Bezel (without the top vertical piece):

Backside showing the reinforcement:

Closeup of the reinforcement:

Before:

After:

I was flipping through some photos I took recently and thought I could spend a few minutes showing off a couple test devices that I use to help figure out problems with my games. I have two devices that I put together that are useful in testing both PCB boards and monitors.

Jamma Conversion Test Board

The first test device I use on a regular basis is my Jamma Conversion Test Board. I wired up a short Jamma harness to a bunch of terminal strips mounted on a piece of plywood. I then take edge connectors of different lengths populated with wires that have spade connectors crimped to the ends of them. I then can hook these up to the terminal points on the jamma board, creating a make-shift jamma harness. This allows me to wire up any board that can be converted to jamma with the normal power requirements. Then I plug the harness of the board into my jamma cabinet. I used this board to test my Frogger PCB last week. It works great and is really handy to test several boards without their cabinets.

My Frogger PCB wired up to the Test Board for testing in my Jamma cabinet

Jamma Arcade Cabinet-In-A-Box

My other device is something I came up after the third or fourth time I pulled parts together to try to test a monitor. I used to test monitors by putting the monitor on a bar stool, pulling an arcade cabinet away from a wall, and hooking the monitor into the cabinet for a quick test. This was difficult and dangerous to do. It was too easy to damage something by dropping the monitor, messing up wiring, etc. I figured out that could assemble the core components of an arcade game: Power supply, isolation transformer, controls, speaker, and wiring into a box. Then all I would have to do is hook up a Jamma PCB with a good test pattern, and a monitor, and I would have a working arcade game. My first box was made out of an old wooden coin box from a poker cabinet. It was made up of pressboard and got wet one day, which ruined the wood. My currrent box is just made out of a plastic tote. It is much easier to lug around, and looks better too!

Old Arcade-in-a-box

Backside of the old Arcade-in-a-box

New rig, top view

Inside view of the new rig

Using the new rig to test out my Centipede monitor after a cap kit

Both of these devices have helped me quite a bit. They were both really easy to put together and I highly recommend building them yourself!

Now that the busy summer is over, it’s time to try to finish up some of my Centipede work before Winter. I’d like to get this game down into the gameroom before it gets too cold to work on it in the garage.
The first thing I needed to do was to buy some more repair parts from Bob Roberts. Bob is a great guy and I often refer people to him for parts. He has several repair kits compiled for common problems. This time I ordered another part for the Centipede monitor since it was still not working as well and I liked. I also ordered parts to rebuild the trackball, because it was totally worn out and needed replaced or rebuilt. I received my order on Monday, and as always Bob included a couple surprises. He sent me a nice little mini-screwdrivers and a small bag of candy for Halloween!

I made sure I took several pictures to show how easy it is to rebuild a trackball. Trackballs wear out badly, and this one was virtually unplayable in its condition. Here are a couple shots of the trackball and the rollers inside before replacement:

Basically these are really easy to work on. Just remove the six screws holding the shell together, and pop off the top of the shell. The ball and roller assemblies lift right out. Two of the rollers have the encoder wheel screwed into the side of them. Just remove the small screws holding those on with an allen wrench. Just be careful not to bend the encoder wheels. Those need to be perfectly flat to work the best. The repair kit I purchased from Bob includes the three rollers, and six sealed bearing assemblies. I also purchased a new white button and a new “snow white” trackball because I liked the look of it more than the offwhite ball, and my old one was really scratched up and worn.

Here are a couple comparison photos of the parts:

Then just put the trackball back together and here’s what you get:

There is a fantastic page on the web covering the original Pac-Man. Jamie Pittman created a Pac-Man Dossier that covers everything you need to know about the Pac-Man arcade game. He has broken down the original program code, and provides a ton of facts such as how the Ghosts determine which way to move around the maze. The Dossier does not provide Pac-Man patterns, since there are already plenty of them on the Internet. What it does provide is crucial information that can be used to make you a better Pac-Man player.

Check out the site here: The Pac-Man Dossier

A friend of mine had a Super Mario Bros upright that needed a cap kit installed. I picked up a few Sanyo 20EZ Cap Kits from Bob Roberts a few weeks ago, and finally got some time to install one of them. Most of the old Nintendo cabinets used the Sanyo 20EZ monitor. They are one of the tougher cap kits in my opinion because there are so many caps, and the writing on the PCB of the monitor is congested. When installing a cap kit, a Cap Map is a really handy document. A Cap Map is basically a layout of the board showing where each cap goes. There was not one available for this monitor, so I made one up. You can download it at the link below.

Here is a quick picture of the board with the new caps installed:

Here is a link to the Cap Map: Sanyo 20EZ Cap Map

From time to time I mention buying parts from Bob Roberts. I just ordered some cap kits from Bob, and received a nice bonus – Halloween candy. The kids were all over it as soon as they saw it! Bob regularly sends free little extras, called lagniappe. It’s just one of the little things that he does that makes it fun to order from him. Bob is a great guy, and has a ton of knowledge. His prices are the best on the Internet for arcade parts, and he has a huge selection. Check out his site!

Now I just need to make time to install some cap kits!

I just wanted to let everyone know of a new site I found out about today through the KLOV Forums. Channelmaniac’s Arcadecomponents’ Old School Repair Logs is a new hosted discussion group that has a really nice breakdown of different repair topics based on game manufacturers and other information. It looks like I have a new site to reference when in trouble!

Jeff Rothe of Rotheblog just posted a story on some Ms. Pac-Man stencils he purchased. This is a nice article explaining how stencils are made for arcade restorations. He also has other articles showing how to properly restore a Ms. Pac-Man cabinet. I’ve not used stencils yet for any of my restorations, but I may do so on my Stargate Multi-Williams project I plan to build.

Rotheblog Ms. Pac-Man Stencils

After working so much on my Tron lately, and not quite getting to 100% working status, I decided to take a break and work on something else. I have a Pole Position 2 that I want to get working, so I can either trade it or sell it to make room for my Donkey Kong 2 project. The last I left this cabinet, it was all taken apart to clean up all the pieces before reassembly. I needed to repair the monitor because it had a broken neck board. And finally the PCB did not work (what else is new in Pole Position stories).

Well, I did the neck board repair over Christmas vacation a few months ago. I will post some pictures of that soon. Also completed a power supply rebuild to get two working AR2 boards. I have a few pictures of this repair below. They both were in need of serious repair, having some of the common symptoms of failed AR2 boards such as burned out resistors from the Sense circuit drawing too much power from the board. These boards were made to monitor the voltage drawn from the PCB they are powering and automatically increase the voltage to ensure the PCB runs properly. This is a great concept, but Pole Positions were so poorly designed that they often would draw more power than the AR2 boards could supply without burning up. This would also cause the PCB edge connector on the Pole Position boards to burn up. There is a quick modification that can be made to disbale this ’sense’ detection, preventing the AR2 board from automatically adjusting the power output.

This week I decided to attack my PCB. The first problem with the PCB was that it did have the classic “edge connector burn” from the AR2 board. I needed to repair this, and do a few other modifications to “bullet proof” the game to prevent future failures.

Burned up resistor on the AR2 board – common!

Disabling the “sense” circuit is just a couple quick jumpers on the back of the nine pin connector

Completed AR2 boards!

Edge Connector Repair

The common repair for a bad edge connector is to just lay down a line of solder to replace missing connector contact pads. That is obviously what the previous owner of this game attempted. This is a very short-termed repair, as it really does not allow for a clean connection. I decided to buy an edge connector kit from Bob Roberts. This kit comes with a female edge connector with solder pins, and a male-to-male edge connector adapter. Basically the concept of this is to solder the female connector over the existing burned-out edge connector on the PCB, then put the M2M adapter in it to leave a male edge connector on the PCB. Since the Pole Position had less pins than the new connectors in the kit, I was able to cut down the adapter to allow wire ties to hold it in the female connector. Hard to explain, but easy to show in the pictures below:

Burned edge connector on the PCB

Burned edge connector solder “repair” removed.

Bob’s repair kit.

Female connector in place over the old edge connector, ready to solder on.

Needed to trim off the excess Male connectors before placing it.

Finished repair.

Another view of the finished repair.

Power Distribution Modification

One of the most recommended fixes I found on the Internet was to distribute the incoming power to the PCB to the various “test points” instead of just from the edge connector. This would allow the power to be more consistent throughout the board, and to cut back on the power draw over the edge connector (remember the burn?). To do this, I soldered wires for the +5v and Ground to as many test points as I could find marked for this. I then ran all of these wires into a molex connector to allow me to remove the board easily. I’ve already had to remove the board 20 times or so, which proves this molex connector idea was a good one! From that connector, I ran a mating molex connector to a terminal strip which I wired directly to the supply voltage in the wiring harness.

Here are some pictures:

PCB with powr wiring soldered onto the test points.

Molex connector and terminal strip used to send the power to the power wiring on the boards.

All connected and ready to go!

Other Repairs to the PCB

There was some visible damage to the PCB. I had to repair some traces that were burned up as a result of the power problems it had. Also had to replace a few smaller components:

Bad trace

A couple burned components repaired.

I wish everything I did so far was enough to fix it. My first attempt at placing it into the cabinet resulted in the following:

Hey, at least it got power! I then adjusted the power supply to get +5v as close as I could, which was easy to do across my terminal strips. Here’s what I got:

Gave me a RAM 6 error. I had a fellow KLOV collector send me a nonworking Pole Position PCB last week in preparation for this repair, so I swapped out the RAM 6 with it. Placed it back into the cabinet and I got:

Another RAM error. RAM 40. I went ahead and swapped that RAM and got the same error again. Before going crazy trying to figure it out, I decided I should check the voltage again. It was low. I then adjusted it again, and immediately heard the game boot up! Here’s the test screen showing all my RAM and ROM was OK, and a screen shot of the game:

However, if you notice I am getting some graphics corruption on the background objects like the mountains and amusement park. Went ahead and tried to swap out some of the custom Atari IC’s that the instructions said contribute to that circuit but got nowhere. I think maybe my 6N Video ROM may be corrupt, even though it passes the self test. Here are a couple more screen shots to show where I’m at:

Finally, I replaced a few other components that were damaged from the battery failure on the CPU board (another death blow to Pole Positions). I had a few new chips, and the rest came from the extra boardset I had. Here’s a quick shot of the bad chips – notice the corrosion on the pins of the ICs:

I had to remove the Optical Sensor from my Tron Rotary Controller PCB. It was cracked and needed replaced. So I thought I might as well show how I did it. I was told that this component was very hard to remove, so I figured I should take extra care to make sure I can pull it out without damaging the board.

Tools Required:

• Soldering Iron
• New Solder
• “Solder Sucker”
• Desoldering Braid or “solder wick”

The following needs to be done with each pin of the component

1. Flow a slight amount of new solder onto the pin. This will help loosen up the old solder. Don’t put too much on, or it will be drawn down through the PCB hole and lock the component in from the other side.
2. Immediately remove the solder with the solder sucker. This is done by removing the soldering iron from the melted solder over the pin, quickly covering the pin and melted solder with the solder sucker, then pressing the button on the solder sucker. This causes the spring action of the solder sucker to suck all of the melted solder away from the pin. If this is done right (which takes a little practice) then there will be little if any solder left over.
3. Use the soldering iron to hold a small amount of fresh solder wick over the pin to draw out any remaining solder from the pin
4. Finally, GENTLY remove the component. There may still be some sticking of the pin to the contacts, so use the soldering iron to hit any stuck pins until they move freely. This is the toughest part, especially with components like IC’s that have rows of pins and can’t flex.

Here are some pictures that I took:

“Solder Sucker”

“Solder Wick”

Solder Sucker removing solder from hot pin

Using the Solder Wick to remove residual solder from the pin

Close-up of the pins after solder removal

Success! The component has been removed.

Here’s what the component looks like after removal. The pins are in great shape with no damage.