Tranquility Base Arcade - Space Invaders Deluxe Repair Log

After - All clean! I am not brave enough for the 'dishwasher method' but have always had good luck using a very soft paint brush dipped in warm water and lightly running it across a board while it is tilted on a 45° angle. Work from the top down. For drying I often pre-heat the oven to 175°, shut it off and pop in my cleaned chassis or pcb. I then let it sit overnight. The key to any cleaning process no matter what you do is to make sure all moisture is removed from the boards before you power them back up. Also be sure to make sure your significant other does not get up before you and decide to pre-heat the oven to 400°!

	Upon powering the game up I was met with two lines of dots which interfered with game play. The dots blocked shots from the base as well as from the Invaders. After some analysis of the PCB I determined I had two bad RAM chips. RAM chip failure seems to be very common on the Midway 8080 boards.
	Here is a picture with one of the RAM chips replaced and one removed with the holes cleaned up. Normally I would socket a repair like this but at the time of the repair I found myself out of sockets!
	This picture shows both of the ram chips replaced. Notice MM5280 is compatible with UPD411. Suitable other replacement chips are TMS4060, MM9060 and D2107C.
	This is the corrected screen after RAM replacement - no more dots! Bring on the Invaders!!!
	Before - A typical dirty chassis from years of neglect. Yuck! What a mess!
	After - All clean! I am not brave enough for the 'dishwasher method' but have always had good luck using a very soft paint brush dipped in warm water and lightly running it across a board while it is tilted on a 45° angle. Work from the top down. For drying I often pre-heat the oven to 175°, shut it off and pop in my cleaned chassis or pcb. I then let it sit overnight. The key to any cleaning process no matter what you do is to make sure all moisture is removed from the boards before you power them back up. Also be sure to make sure your significant other does not get up before you and decide to pre-heat the oven to 400°!