Question from Jason: Hi Jonathan. My name is Jason and I wanted to thank you for sharing your insights and expertise for the benefit of collectors everywhere! I recently jumped into the arcade world by acquiring a Space Firebird cocktail and the journey has been a lot more enjoyable thanks to your tutorials. It’s a tremendous benefit to the arcade community! After adjusting the various monitor pots (according to your advice), I was able to turn a high contrast and distorted screen into a crisp, clear image. When I picked it up, the person thought it would have to be recapped, or possibly require a new monitor, so I’m grateful for your guidance!

After about two weeks of great gameplay, however, I turned on the machine and the game began to display erratically. Essentially the various sprites (such as the attacking birds in the game) would often be “twinned” with a ghostly counterpart that would flicker in and out of view as the bird swooped around screen on the attack. Aiming for the ghost image didn’t destroy the enemy bird, only if you aimed for the “real” bird, so the collision detection was still working. Overall, the ghosted sprites would range from a nuisance to downright irritating, particularly when big swarms of birds were on the attack. Essentially, the presence of the ghosts weren’t predictable. Sometimes they seemed to calm down, in other cases they seemed to plague a lot of the sprites.

In addition to the twin ghosts, the game would display other erratic behavior. For example, the phrase “10 Best Scores” during attract mode would drop characters outright or substitute in a different letter or sometimes you’d see an overlapping twin ghost letter flicker slightly off to the side so it might look like it was out of focus if you were looking through binoculars. In other cases, characters would be displayed in a different area although along the level or plane of the game where it should be. For example, in the bottom right corner where “Credit” would display during attract mode and gameplay, the “I” would sometimes display in the very middle bottom of the screen.

I’ve attached a picture to try and illustrate some of these issues, although I hope my general description gives a clearer picture (no pun intended!). In the attached image, you’ll see that the bird on the far left has pieces of it ghosted to either side; you’ll see an “R” ghosted on the far right of the “Space Bird” text; at the very top, you’ll see a piece of the “bird” graphic (to represent the number of enemy birds remaining on any give stage) is displayed over the number 09; along the very bottom, you’ll see the “I” of CREDIT displayed below the ship. Yesterday I checked the power supply as you suggested in the video. The DC was about 5.4, so I adjusted it down to 5 volts but the problem persists. One person suggested I check all the socketed components and re-seat them. Based on my description, what “next steps” would you advise in troubleshooting this problem? I would be extremely grateful for any insights/suggestions! Thanks again for your help, Jason

Picture: https://docs.google.com/open?id=0B66ffvBk6gbuNzQwYmUxZmEtNDJjNC00OTVlLTg0Y2UtZmU2NTFlYTc5NGUy