Asteroids has the shakes!

[OTTOgd]

Since receiving the game, it has received new cap kits (monitor and game boards), new brightness/contrast pots, 'big blue' as well as re-flowing the PCBs' connector solder. But I am still a monitor trouble-shooting newb.

I finally got my Asteroids back up and playing after replacing a bad transistor but the graphics still 'shake' inwards intermittently. Thoughts?

Also, there is also a bit of curl on the very lower half of the screen, crossing just under the 1979 Atari words. One of the X or Y pots need adjusting, perhaps?

Thanks for looking.

 

[modessitt]

Can you upload a video to youtube and embed it here?

 

[OTTOgd]

Here it is:

And, yes, I have micro-switch buttons installed at the moment. Sheesh.

 

[toolguy]

My Asteroids had very, very, similar. I figured it out, thinking about what it possibly could be.

I ended up replacing all five of the small pots on the monitor deflection board.

All of course were 30 years old and their resistance was not what it should be anymore.

After doing that, no more shakes!

Before doing that, I replaced both X Y pots at one point but that did not help.


You can try to rule out the X Y pots, by putting it in test mode and then centering the picture.

 

[OTTOgd]

Hey, that makes sense and would account for the slight curl at the bottom as well, I suppose, if they were loose/jiggly. Thanks for the tip!

 

[toolguy]

Hey, that makes sense and would account for the slight curl at the bottom as well, I suppose, if they were loose/jiggly. Thanks for the tip!

Just added this to my post above....


"You can try to rule out the X Y pots, by putting it in test mode and then centering the picture to make sure it is where it should be. "

If the pots are just bad, then this check will not help, but it will tell you if the pic is where it needs to be.

I replaced all my pots, even the X Y with the same Bourns brand pots. I like those pots and they are exact fit.

 

[Snarly]

Pots....

Where did you get the new pots?
Thanks,
Chris

 

[OTTOgd]

Where did you get the new pots?
Thanks,
Chris

Bob Roberts has them ... as well as tons of other good stuff ... and very helpful information:

http://therealbobroberts.net/pots.html

 

[Snarly]

Thansk for the quick post:

What type pot? What specs?
Do these get soldered in?

Thanks,
Chris

 

[toolguy]

Where did you get the new pots?
Thanks,
Chris

Sorry! I ordered mine from Mouser Elec. I searched the Bourn site too for part numbers and values. I wanted exact fit/footprint, Roberts did not have.

I searched my old orders there and found it for the 4 deflection board pots.


http://www.mouser.com/Search/Produc...virtualkey65210000virtualkey652-3352E-1-102LF