Asteroids G05-802 "wavy" vectors

th0r

New member
Joined
Sep 11, 2010
Messages
5
Reaction score
0
Location
BC, Canada
Hello everyone,
Be nice I'm new here.

I recently acquired an Asteroids cabinet that is working, and is in decent shape but has a display issue.

I just finished reading the whole thread on kentmurphy's asteroids delux that ended up being a bad yoke.

I am not sure I have the same problem since none of my vectors are broken, they are just wavy (static wavy, not moving around wavy).
I'm hoping it is just an adjustment or combination of adjustments?

I have tried adjusting the x/y gains, and the pots on deflection board R600/602 R700/702
with little or no success.

Any suggestions?

http://picasaweb.google.ca/thorhargrave/Asteroids#5515581819551851794

Thanks
Thor
 
Hello everyone,
Be nice I'm new here.

I recently acquired an Asteroids cabinet that is working, and is in decent shape but has a display issue.

I just finished reading the whole thread on kentmurphy's asteroids delux that ended up being a bad yoke.

I am not sure I have the same problem since none of my vectors are broken, they are just wavy (static wavy, not moving around wavy).
I'm hoping it is just an adjustment or combination of adjustments?

I have tried adjusting the x/y gains, and the pots on deflection board R600/602 R700/702
with little or no success.

Any suggestions?

http://picasaweb.google.ca/thorhargrave/Asteroids#5515581819551851794

Thanks
Thor

Purchase a new "Big Blue" from The Real Bob Roberts and change it out, i would start there anyways.

Good luck,
 
Thanks for the quick response.

If I am going to start replacing capacitors etc, and have to pay for shipping anyway.

What other items should I consider buying from the real bob roberts?

So far my list includes:

-Atari "Big Blue" Capacitor - (Transformer assembly)
-GO5-802 19" B&W X-Y w xsistors
-Atari Asteroids Short Button Set (just because mine are dirty/pitted)

Is there anything else that is hard to get or I should expect will fail and need to be replaced?

thx
 
I did try to adjust the pots:

"I have tried adjusting the x/y gains, and the pots on deflection board R600/602 R700/702
with little or no success."

I can make the screen squish and stretch on the x and y but can't seem to get rid of the wave in the vectors.

The outside of the test pattern is a perfectly straight rectangle.

I looks like the center of the screen is "square or a diamond" but it seems like a ring between the center and the outside of the monitor is stretched causing the wavy vectors.

Am I correct in believing that R600 and R602 on the deflection board adjust the same thing but one is a coarse and one is a fine adjustment? ( same with R700 and R702)?

Any suggestions on how to properly adjust the pots would be welcome.
correct order of adjustment etc.?

When I get a chance to i will take a picture after fiddling with the pots


Thanks

Thor
 
If you leave it on for an extended period does the screen seem to slightly 'breathe'?

If you plan on keeping it and since you asked here is what I did. New big blue and fuse holder. AR rebuild, monitor rebuild with transistors, board cap kit, reflowed every header pin and lots of other parts till it looked new and cleaned up all connectors to like new.

Mine worked but would have the waves like you described and mine would start to breathe after a while. Have run it quite a few times 10+ hours and it is rock solid so far.
 
Looks like you need to adjust the pots on the deflection board.
Yep, that's exactly the problem - linearity. Adjust the linearity pots on the deflection board. It's an iterative process because the pots will affect each other. Be patient and you can make it look good.
 
I uploaded a video of the attract screen to youtube - you can see asteroids getting larger when they move to the center and smaller as they get closer to the sides.

watch the large asteroid that crosses the word coin at aprox 27 sec.

http://www.youtube.com/watch?v=pzQ811elw0M

I will spend a little more time fiddling with the pots before I order any parts.

I will let you know how I make out.
 
I uploaded a video of the attract screen to youtube
http://www.youtube.com/watch?v=pzQ811elw0M
Definitely linearity. You should adjust it using the crosshatch (diamond) test screen. Try to make the lines as straight as possible. This will fix your problem. You may have to replace the pots if they aren't having the desired effect.
 
Some success.

I think what I have discovered is that in the Y-axis the R600 pot adjusts the entire screen where the R602 pot adjusts the outside of the screen. The same is true for the X-axis and the R700 / R702 pots.

After figuring this out, now I can adjust the outside of the screen to "straighten" the test pattern

After adjusting, I could not get the test pattern to fit on the screen with it straightened.

So from there I had to adjust X and Y Gains to get the screen to the correct size.

The screen is much better now, and now that I think I understand what is going on and how the adustments work, I think I can get it even better after a little sleep.

Thanks everybody for all the help and suggestions.

I'll post a pic of how close I can get it when I'm done fiddling.

Thor
 
Back
Top Bottom