Tempest "warping" image

retroshaun

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So my recently repaired Tempest seems to be working nicely aside from one thing. When you complete a level and "warp" through the web, where the web goes off the sides of the screen (mostly noticeable on the bottom of the screen) the vectors bend in a pretty major way - I mean, they probably warp about an inch or so to the left or right, in about the bottom 2 inches of the screen.

Someone told me it could be the brightness - does this sound correct? Anything else to look at? The monitor was just repaired and thoroughly checked as was the PCB.

Everything looks just fine on the test screens.
 
So my recently repaired Tempest seems to be working nicely aside from one thing. When you complete a level and "warp" through the web, where the web goes off the sides of the screen (mostly noticeable on the bottom of the screen) the vectors bend in a pretty major way - I mean, they probably warp about an inch or so to the left or right, in about the bottom 2 inches of the screen.

Someone told me it could be the brightness - does this sound correct? Anything else to look at? The monitor was just repaired and thoroughly checked as was the PCB.

Everything looks just fine on the test screens.

You could try adjusting the size pots on the game PCB down a little bit if you think it is drawing off of the screen. Also, there are problems with warping between levels on the old ROMs, but it is usually on the left side. ROM version 3 is the one that supposedly fixed the warping problem.
 
Its definably drawing off the bottom of the screen thats for sure but would it cause this issue? And it *only* happens on level completion.

I didnt realize there were rom updates so I'll take a look - how can I tell which revision I have installed? Will it be marked on the roms I guess?
 
Its definably drawing off the bottom of the screen thats for sure but would it cause this issue? And it *only* happens on level completion.

I didnt realize there were rom updates so I'll take a look - how can I tell which revision I have installed? Will it be marked on the roms I guess?

One difference is that the original spinner output in Test mode output characters for the current value. The 1st printing manual shows an "A" character in the sample screen. There was an update that changed the spinner test to show a line spinning or something like that according to an update from Atari for the manuals. I don't know if the spinner change was in version 2 or 3 though. You might check the stickers on the ROMs to see if it is visibly labeled correctly. Mine has the problem and I don't remember how I verified I am on ROM version 1. I'm going to update mine at some point and probably just kit it with Tempest Tubes at the same time. :D
 
Well I definitely have hex codes for the spinner test so I guess that helps. I'll take a look later.

When you say that the problem is on the bottom of the screen, are you indicating bottom while mounted in the game or bottom with it horizontal on the bench? :) That would make a huge difference...

Either way, looks like you have older ROMs and an update wouldn't hurt. There was another issue that was fixed switching between player 1 and 2 that also caused a monitor glitch. Also a credit glitch that could give players 40 credits 12% of the time if their score was over !79,000 or something like that. :)
 
So my recently repaired Tempest seems to be working nicely aside from one thing. When you complete a level and "warp" through the web, where the web goes off the sides of the screen (mostly noticeable on the bottom of the screen) the vectors bend in a pretty major way - I mean, they probably warp about an inch or so to the left or right, in about the bottom 2 inches of the screen.

Someone told me it could be the brightness - does this sound correct? Anything else to look at? The monitor was just repaired and thoroughly checked as was the PCB.

Everything looks just fine on the test screens.

Tempest draws the vectors off the screen during the warp portion. There's a hack that can be done to the boardset to prevent this (since this was hard on the monitor); by adding some diodes, you can restrict the vectors from going off the screen. When they reach the edge, they'll quit moving in one of the directions that would take it off the screen. I have a Tempest here that does the same thing and it has the hack. Look on your boardset near the lower/middle edge of the boardside with the edge connector and see if you have some diodes that look to be added.
 
Tempest draws the vectors off the screen during the warp portion. There's a hack that can be done to the boardset to prevent this (since this was hard on the monitor); by adding some diodes, you can restrict the vectors from going off the screen. When they reach the edge, they'll quit moving in one of the directions that would take it off the screen. I have a Tempest here that does the same thing and it has the hack. Look on your boardset near the lower/middle edge of the boardside with the edge connector and see if you have some diodes that look to be added.

I knew I'd read this somewhere before...turns out it was from my own website! I gotta read that thing more often :)

http://users.rcn.com/jenison/mars/trouble/man/atari/game/tempest.html

Symptom: Deflection overdriven
Between the X-out test point and ground connect 2 6.8 VDC zeners connected in series, banded end to banded end. For the Y-out you use 5.6 VDC zeners.

Look to see if your boardset has this hack done to it.
 
Mine does the same thing, I have just lived with it...but it does bother the crap out of me.

Also, if it matters V3 of the ROMs do not "fix" it. I have V3 on my board.

Someone mentioned upgrading from 1 to a newer version. From memory, so check me if anyone does anything. V3 used 1/2 the ROMs (by number) as V1 and 2. Of course they were larger for V3. Tubes is setup to replace a single ROM in a V1 or 2 setup. If you want V3 ROMs on a board set up for v1 or 2 you need to split apart the ROMs yourself or, as I happened to do just before I went to split them, find copies of 3 already split. (You may also be able to restrap the board..I did not look into it.) Tubes will run with V3 ROMs. Apparently nothing was changed in the level portion. If you want to run Tubes on a factory V3 setup you need to splice it into the correct half of the appropriate ROM.
 
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