There isn’t much new to report regarding our arcade projects, so let’s start this post with a monkey playing pac-man:

In non monkey related news….I ordered a ton of capacitors, IC sockets, and TTL chips (mmmmm….chips) from eBay. I’m tired of not having parts when I need to fix something, and figured it would be a good idea to stock up on common parts. I also got everything dirt cheap, which is always good.

When I got Breakout, I was told that the monitor kept blowing fuses. I changed all the capacitors on the chassis, and the Horizontal Output Transistor, hooked it all back up, and turned it on without the game board hooked up. The monitor powered up and the neck of the tube glowed, and no fuses blew, which is good cuz that would really blow. So, I *think* I fixed the monitor. I hooked up the game board, and couldn’t get it to show any video or make any sounds, so I’ve got more work to do. I’m pretty clueless with a lot of this stuff…my lack of knowledge tends to make this a slow process, but I’ll get it going eventually.

I also tried to figure out what was causing the score problem on Demolition Derby (see the posts in the “Demolition Derby” category). I tested all the ICs in the circuit that controls the scoring using a method described by Randy Fromm, and couldn’t find any bad ones. There were 4 capacitors on the board that looked pretty worn out, so I replaced them. I fired it back up, and it didn’t fix the problem. It did however, kill the sound in the game. So now I have 2 problems to fix instead of one. There is a giant orange 4400mfd capacitor on the board that looks pretty spent too. I ordered a replacement for that from Mouser.com.

This is just a short post to update on the status of fixing the score/timing problem with Demolition Derby (see my earlier post in that category). I got a package of goodies from Bob Roberts today. In that package was a bunch of parts I ordered to get Moon Patrol and Pac-Man working, a power supply repair kit for Battlezone (I’ll explain in another post), leg levers, some tools, moon pies and mardi gras stuff…AND the capacitor that I needed to swap for Demolition Derby.

I put the new cap in, and it didn’t fix the problem. Oh well…probably should have been replaced anyway. I poked around on the board a bit, checking it over for problems. I was able to find the section on the board that corresponds to the timing and score. It has quite a few repairs on it, but everything seemed OK as far as I can tell (and I can’t tell much! ). I’m not touching this again at least until I finish watching my training DVDs from Randy Fromm.

I should be posting soon about a new game that we are getting soon, knock on wood. I won’t mention it’s name so I don’t jinx it.

I’m off to build some power supply boards for Pac-Man and Moon Patrol.

OK…the insanity continues. We picked up another game in Hudson, MA called Demolition Derby. It’s from 1977, and is the oldest in our collection.

I was on the fence about this one, but Linda had to have it. She likes driving games. This game has a black and white monitor, and very old looking graphics. Everything on it is in great shape for it’s age. I really like the shape of the cabinet, and the backglass with the old cars smashing into each other. The game has one small problem. Where the score and time should be at the top of the screen just shows white blocks. I checked the voltage going to the game board, and it was low - 4.4 volts. I upped it to 5.1, and the blocks started to appear different. They are now all jittery and you can sometimes see the numbers. This leads me to believe that the problem is not with the game board, and may be with a big blue filter capacitor in the power supply. I’m going to try to locate one and see if it fixes the problem. You can see what it looks like now in this video: