qbert qubes graphics issues

tron guy

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so I picked up a dedicated qubes 6 or 8 months ago. turned it on when I picked it up and it worked (on for 1-5 minutes maybe).

The machine has been on a maximum of 1 hour in the 6+ months I"ve owned it. Not 1 hour at a time, 1 hour total.

anyway, I flipped her on the other day and there are graphics issues. blockiness, weird letters, it's just off.

Voltages are solid, (a switcher has been hacked in before I got it).

Anyway the picture I am about to show you has a couple of 'blown' parts near the edge connector.

In someone's expert opinion (not a guess from someone who has no idea), is it possible these parts blew since I've had the machine and they are causing the issues described above.

The power cord is missing the ground prong, and when I plug it in, I get a little sparking and it's kind of rough to get it plugged in, meaning it kind of goes on and on and off and on, until I shove it in hard (that's what she said).

I did reseat all of the socketed chips, that's how I discovered the 2 blown parts (both pictured. 1 transistor and 1 capacitor) positions Q1 and C33 (pictured)



I suppose another way I should ask this is:
could the game have functioned normally with these parts blown?
 

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I dont think your issues are with those parts. They arent blown, theyve been removed from the circuit. Theres also a resistor missing looking at the pic. Id guess its more to do with a mod of some sort. Your issues are likely RAM related or an addressing issue.
 
Have you cleaned the edge connectors on the pcb? My Ms Pac did the exact same thing until I cleaned the edge connector for the harness.

On second thought you should just forget it and not waste your time. Send it to me and I shall relieve you of all your troubles. :D
 
if it comes up to random chars and does nothing else, the ram select is not getting power.

check the following section (green = 5v, red = 12v ~ ) see attached image.
 

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I would say the gameplay is flawless as far as performing properly. It says "hello I'm turned on", it comes up with a pretty good screen. Just some of the things are messed up, making me think it's 1 or 2 chips that are the culprit. AGain I know nothing of it, but it's not an across the board problem.

I reseated the chips, cleaned the harness, cleaned the edge connecter, double checked voltages.

It's still the same. No matter, I've had it on 3 times for 15 minutes each time in 6 months, it's not like it gets a lot of play. I'm guessing the problem was probably there, or almost there when I got the game, hard to know for sure since I haven't played it really.

though the few times I had it on, it did not have any issues. I simply moved the game across the garage, (softly and carefuly) plugged her in and now this.
 
Pictures?

is it FG or BG graphics that a messed up?

iqnore my previous post if it gets pas solid blocks of letters.

"Hello i'm turned on" is a false indication if working or not.
 
ok I will post as quite a few pictures here.

forgive me I cannot for the life of me figure out how to take a picture of a freaking monitor without getting glare, etc.

You can see in some of the pictures, the words are wrong. When the game turns on and qbert is scrolling horizontally to print text, he is surrounded by blocky graphics.
 

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more pictures
 

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That transistor and resistor are part of the coin meter circuit and are not causing your problem.
Where are you checking the voltage at? Qberts suffer from alot of voltage drop from the power supply to the main board. Always check and adjust 5v while measuring on the main board. Low 5v will cause screwy graphics but the game will sometimes still play if its borderline.
For the record, I think qbert is one of the few games you should stick to the linear supply with.
 
That transistor and resistor are part of the coin meter circuit and are not causing your problem.
Where are you checking the voltage at? Qberts suffer from alot of voltage drop from the power supply to the main board. Always check and adjust 5v while measuring on the main board. Low 5v will cause screwy graphics but the game will sometimes still play if its borderline.
For the record, I think qbert is one of the few games you should stick to the linear supply with.

I checked about 10 of the chips (74's?) had it at 5.08 or so on all of them.
I agree, about the original power supply, but I didn't make this modification. The fact that I've owned this game for almost 8 months and it's seen 1 hour of action (total) indicates the amount of time I've had to mess with it.

I think the original owner wanted to buy it back. But I've waited about 2 or 3 months for that to materialize, so it's 50/50 if he gets it back at this point.
 
looks like a possible issue around the foreground object select register, (93419) E2-3 **, try swaping with E1-2** or E4** and see if problem moves to position (E4 is Vert, E1-2 is Hori)

also check the voltage per riptor, use one of the filter caps on the edge of the board.

however, i disagree on the linear power supply :p, but then i also don't suggest using a cheap switcher either. (prefer a good beefy Heavy duty Switcher, or ATX Power supply.

** i dont remember if these are socketed?
 
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