Picked up two early stand-up video games (Asteroids and Centipede) from a basement in Cleveland. Would like to get them working and/or move them on to someone that would like them. First up is Asteroids and I could use some help.

Game boots, and in test mode I hear the tone when pressing each button. When a game is started game play seems to work normally (correct sounds and control operation) except for the monitor. I'm not quite sure how to describe this, but its as if the entire screen is compressed down to a single narrow vertical line in the middle of the monitor. That vertical line goes from the top edge of monitor to the bottom edge. We all know the ship appears in the middle of the screen. If I don't apply any thrust and just apply constant rotation while also firing constantly, I see the "bullets" traveling straight up and straight down along that narrow vertical line in the middle of the screen. The rest of the screen is completely blank, and the vertical line isn't solid white.

I tried to determine what monitor I might have (monitor manufacturer and model) by looking in the back access panel, but I could not tell - printing on labels and such is pretty faded. I did snap a few pictures though to post here as I know some of you can identify the monitor just by what the boards look like. Of course this thing didn't come with any papers/manuals.

Where do I start to diagnose this? I removed and re-seated the edge card connector and there was no change. Haven't done anything else. I'm a newbie when it comes to video arcade games, so feel free to post advice and links to resources a newbie can use to learn more.

Also, if anyone in the Cleveland area is interested in taking a look at these 2 vids then please shoot me a PM.

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I'll remove the board and reflow the male header pins. Will report back results tomorrow.

If I need to replace the transistors, what are they (may have some from pinball parts supply), and would I need to discharge the picture tube in order to be able to safely work on replacing the transistors?

Nice site. I see I can get control panel overlays there too. I notice there are multiple cap kits offered there for Electrohome XY monitors. I don't know which model I have, and the writing on the model/serial number sticker is too faded for me to read. Do you know which model was used in the Asteroids (not deluxe) games, or which specific cap kit and flyback kit would be appropriate for this monitor?

Thanks for that.

Its much easier to search when you have a phrase to search on! I see just a vertical line which would make me initially think horizontal collapse, and in this game the monitor is mounted so it is longer horizontally than vertically so I am looking at horizontal collapse, correct?

Also, I just read something that said not to directly ground the anode on a black and white monitor to discharge it. What method is best used to discharge this type of monitor?

Ok, progress has been made but still more to go.

Today I made a monitor discharge tool, went the screwdriver + 10 100k ohm 1/2 watt resistors in series with a pigtail and alligator clip route. I did this because I read that a direct discharge of the G05-801 monitor is not recommended. I metered the resulting tool and it metered pretty close to 1000k ohms. With the power cord unplugged, I clipped the alligator clip onto the monitor frame and probed around under the suction cup. Never did hear a "snap" like I expected to, but I left the tip in place long enough that I'm guessing the monitor did in fact discharge.

I then removed all connectors from the vector board, reflowed all the header pins and reinstalled the vector board. Powered up and I no longer have a horizontal collapse problem. The ship was very dim though so I turned up the brightness and could then see the ship and the surrounding asteroids. Yeah!

However, another problem can now be seen as shown in the picture below. I don't know if this is a new problem or just a problem that couldn't be seen until the horizontal collapse issue was fixed.

I did some reading in the bw_vector_monitor_faq document and realized the lines could simply be brightness turned up too high. So I did as suggested and turned the brightness down, then up until the image was visible and then adjusted the contrast. The result - a correct looking screen with no extra lines!

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Thanks for confirming, I was thinking that's how the monitor was designed to work once I noticed the retrace lines are dimmer than the other artifacts.

My monitor had been powered up within a day of working on it, so I knew I needed to discharge it. I metered my homemade discharge tool before using it and observed 981k ohms resistance. With the game unplugged and one end of the tool clipped to the monitor chassis I was able to probe the other end of the tool under the suction cup. I'm sure I was able to hit the correct spot, and I held the tool in place for several seconds, moved it a bit and held it there, did that a few times. Never did hear a "snap" though. Could that be due to a more gradual discharge using a tool that has built in resistance????

Was only on briefly like that. Made the adjustments and all looks good, including no dot in the center!

Good, was hoping it was like that. So how long should I hold the probe in place under the rubber cup when discharging each time using this method?