Color vector on an analog oscilloscope?

Smart Bomb

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Quick question, I have an oscilloscope which I just learned how to get Asteroids to show up on the screen of scope. Would I have to do anything different to the scope settings to have a color vector show up on it? Or are the settings universal for all vector games, color or not?

(I am not near the scope or the games till about another two weeks...just wanted to know if anything needed to change when I got back to the games and scope)
 
Yep, same hookups, and it will be monochrome.
 
The settings are exactly the same. X and Y deflection.

The color is handled by the Z signal, which basically controls which guns of the tube fire at any given time, as the objects are being drawn. But the X and Y drawing signals (which deflect the beam) are the same for b/w vs color, and that's what you're looking at when you connect a scope to XOUT and YOUT.
 
The settings are exactly the same. X and Y deflection.

The color is handled by the Z signal, which basically controls which guns of the tube fire at any given time, as the objects are being drawn. But the X and Y drawing signals (which deflect the beam) are the same for b/w vs color, and that's what you're looking at when you connect a scope to XOUT and YOUT.
I thought Z handled the brightness? I did not hook up the Z when I did the Asteroids...Z would help me remove the dots in the asteroids, correct?
 
I thought Z handled the brightness? I did not hook up the Z when I did the Asteroids...Z would help me remove the dots in the asteroids, correct?

Yes, Z is the brightness. The only difference with a color tube is there are three brightness signals from the game board to the monitor (each controlling the R, G, and B guns). Versus in a b/w monitor where there is only one brightness signal, controlling one gun.

The Z signal isn't necessary to connect to a scope when debugging. (Plus, you can't really connect the Z signal directly on most scopes. It won't work right unless you scale and I think invert the Z signal. @VectorCollector probably knows the details. Someone here used to sell a small board that would do it for you.)

However you aren't using the scope to debug anything related to Z. You're mainly using it to determine of the X and Y drawing signals are correct, so you know the picture is being drawn roughly correctly (and doesn't have any issues like H or V collapse, or half of the screen is missing, or everything is drawn wonky, etc.) You're using it as a safety device, to check the signals and make sure they are safe before connecting the monitor.

You basically just need to check the test mode crosshatch, then if that's ok, pop out into attract mode, and make sure everything looks roughly ok.

If X and Y are ok, you can connect to your monitor and use that to debug any Z issues, or any more fine graphics issues that you can't see on the scope.
 
Yes, the Zinv adapter is nice if you basically want to also read the text, i.e. any RAM/ROM/POKEY fault alpha in TEST MODE is easier to read with the Z controlled to remove the extra lines etc. It is very satisfying to see the game play on a scope just like it would on the vector monitor. :)

I don't sell anything anymore, so you'd have to look elsewhere.

 
Tested space duel and tempest…all i get with space duel is a collapsed image horizontally and all i get with tempest is a single white dot in the middle. Couldnt test asteroids deluxe because the game wouldnt turn on..power issues, I didnt trouble shoot it..i will another day.
 
Are these games of yours that aren't working?

Is the Tempest playing blind? There's no sense in testing the XY output if it isn't playing blind, as the output will be garbage. However a game can play blind and also have video section issues, where you can still get no picture (or a collapsed or otherwise messed up picture on the scope). So playing blind is a necessary but not sufficient requirement.

If you were getting collapse in one case, that means you probably at least have the scope hooked up right. But you really want to be able to get a good image from a known working game to be 100% sure.
 
Are these games of yours that aren't working?

Is the Tempest playing blind? There's no sense in testing the XY output if it isn't playing blind, as the output will be garbage. However a game can play blind and also have video section issues, where you can still get no picture (or a collapsed or otherwise messed up picture on the scope). So playing blind is a necessary but not sufficient requirement.

If you were getting collapse in one case, that means you probably at least have the scope hooked up right. But you really want to be able to get a good image from a known working game to be 100% sure.
Yes..they are my games. And I tested the scope on my Asteroids (with the working board I bought from u, so scope is working and set up correctly to show an image).
 
Cool. In that case you know you have game board issues. (Though for the Tempest, you should check the fuses on the brick first, as you can get a dot on the screen when there's no power to the video section. Also, check the +15 and -15V for the video section.)

If you want to send the Space Duel or Tempest boards in, PM me.
 
Cool. In that case you know you have game board issues. (Though for the Tempest, you should check the fuses on the brick first, as you can get a dot on the screen when there's no power to the video section. Also, check the +15 and -15V for the video section.)

If you want to send the Space Duel or Tempest boards in, PM me.
Thanks..but i need to learn how to work on the boards…i can do so,e trouble shooting..im not in the "matrix" yet though.
 
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