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edwin128

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Hello. I would to ask a question, I don't know if it's a basic thing or not.

I have three different pcbs: Figting Raiders, Strikers II, and guerrilla wars. I used them with a Mak Strike supergun and a ATX psu.

I notice that for example the shadow sprites do not show correctly and have vertical lines. Or when the character respawn and is transparent, it does have the lines. Once the sprites are solid these are gone.

I am wondering if maybe the voltage of the PSU (which is close to 5V) ma be a problem. I tried two different LCD screens and the problem remains.

It's strange that is happening to 3 different pcbs. So, could it be something elses?

Thanks for your help, Edwin.
 
either in the monitor or just after the jamma connector, there's a scaler. That's probably the issue, according to your description.
 
either in the monitor or just after the jamma connector, there's a scaler. That's probably the issue, according to your description.
Hi @Asayuki. Thx for your reply. I don't have any external scaler, the video signals goes from the supergun using the scart cable to the lcd screen.

This means that lcd screens do not show properly the image.

do you know if an scaler to hdmi could help to solve this issue?

cheers, Edwin.
 
The supergun itself might contain a scaler. LCD monitors all have their own internal scaler that serves the purpose of adapting the 15kHz scan rate to something acceptable by the display panel. Try with another monitor or with another supergun first. If you don't have another supergun you might want to consider buying yourself a cheap GBS8200. There are better scalers, with HDMI outputs if you wish, but serious ones are going to cost $$$. A GBS8200 is not compatible with everything but it's just around 20-25 bucks.
LCD monitors are notorious for not getting along well with some arcade boards. The only definitive solution is an arcade grade CRT monitor.

I hope this helps.
 
The supergun itself might contain a scaler. LCD monitors all have their own internal scaler that serves the purpose of adapting the 15kHz scan rate to something acceptable by the display panel. Try with another monitor or with another supergun first. If you don't have another supergun you might want to consider buying yourself a cheap GBS8200. There are better scalers, with HDMI outputs if you wish, but serious ones are going to cost $$$. A GBS8200 is not compatible with everything but it's just around 20-25 bucks.
LCD monitors are notorious for not getting along well with some arcade boards. The only definitive solution is an arcade grade CRT monitor.

I hope this helps.
Yes. I'm still waiting for my cga2vga converter to arrive from china.
I was also wondering if using a ATX psu to power these pcbs instead of a regulated could be the issue.
I'm sure that the voltage was closed to 5V, never superior to that value.
 
can you test another PSU?
A friend of mine also had some issues using a cheap ATX PSU to power a Naomi in his NAC.
After the new PSU his image problems where gone.
I'm pretty sure he had something like lines in the image as well...
 
can you test another PSU?
A friend of mine also had some issues using a cheap ATX PSU to power a Naomi in his NAC.
After the new PSU his image problems where gone.
I'm pretty sure he had something like lines in the image as well...
Hello Pascal. Thx for the info. This not related to the naomi1 you sold me. It's working fine. This is happening with my other pcbs.
Yes, I'm getting a new psu soon with a adjustable 5V to see if there is any difference.
Cheers, Edwin.
 
The problem my friend had also wasn't related to his Naomi, but to the ATX PSU he used to power the Naomi.
For all other (Jamma) PCB's he used the stock PSU from his cab without issues ;)
 
This is curious. Ok, ATX PSUs are the cheapest thing ever and therefore have so many issues, but it's the first time I hear them being able to generate video artifacts on screen.
Sure they are noisy as **** and this noise can travel back to the display via the AC power lines or via ground.
Sure the output voltage isn't the best regulated thing ever, expecially on the 12V branch.
Current capacity and transient response may also be an issue, expecially considering that Jamma (and expecially pre-jamma) stuff is designed with a very clean (linearly regulated back then) power supply in mind.
I would really like to see a picture of these lines caused by the power supply. There's definitely something new to learn for me here.
Also, maybe edwin128 should post pictures of what he is seeing as well, for a comparison.
 
The problem my friend had also wasn't related to his Naomi, but to the ATX PSU he used to power the Naomi.
For all other (Jamma) PCB's he used the stock PSU from his cab without issues ;)
Ah ok. He did had two psu unit. I have only right. I'm getting a regulated one soon.
This is curious. Ok, ATX PSUs are the cheapest thing ever and therefore have so many issues, but it's the first time I hear them being able to generate video artifacts on screen.
Sure they are noisy as **** and this noise can travel back to the display via the AC power lines or via ground.
Sure the output voltage isn't the best regulated thing ever, expecially on the 12V branch.
Current capacity and transient response may also be an issue, expecially considering that Jamma (and expecially pre-jamma) stuff is designed with a very clean (linearly regulated back then) power supply in mind.
I would really like to see a picture of these lines caused by the power supply. There's definitely something new to learn for me here.
Also, maybe edwin128 should post pictures of what he is seeing as well, for a comparison.
The atx psu is not noise at all. The vertical lines appear in the shadows for the character sprites. I will post the pic monday when I got the regulated psu, I don't want to power them up with the atx psu unit anymore.
 
Sorry for the technical lingo. I meant "electrically" noisy; not in the sense of appalling sound.
 
This is curious. Ok, ATX PSUs are the cheapest thing ever and therefore have so many issues, but it's the first time I hear them being able to generate video artifacts on screen.
Sure they are noisy as **** and this noise can travel back to the display via the AC power lines or via ground.
Sure the output voltage isn't the best regulated thing ever, expecially on the 12V branch.
Current capacity and transient response may also be an issue, expecially considering that Jamma (and expecially pre-jamma) stuff is designed with a very clean (linearly regulated back then) power supply in mind.
I would really like to see a picture of these lines caused by the power supply. There's definitely something new to learn for me here.
Also, maybe edwin128 should post pictures of what he is seeing as well, for a comparison.
@Sp33dFr34k, do you still have some pictures of the video noise when you used the ATX PSU with your Naomi?
 
This is curious. Ok, ATX PSUs are the cheapest thing ever and therefore have so many issues, but it's the first time I hear them being able to generate video artifacts on screen.
Sure they are noisy as **** and this noise can travel back to the display via the AC power lines or via ground.
Sure the output voltage isn't the best regulated thing ever, expecially on the 12V branch.
Current capacity and transient response may also be an issue, expecially considering that Jamma (and expecially pre-jamma) stuff is designed with a very clean (linearly regulated back then) power supply in mind.
I would really like to see a picture of these lines caused by the power supply. There's definitely something new to learn for me here.
Also, maybe edwin128 should post pictures of what he is seeing as well, for a comparison.
@Sp33dFr34k, do you still have some pictures of the video noise when you used the ATX PSU with your Naomi?
Sadly I don't, but if the TS can post a picture, I can check if it's the same as what I was experiencing. For me the ATX PSU was the problem as it was creating vertical "waves" in the image, best visible when booting the Naomi as you have a solid white screen then.
 
Vertical waves like horizonatal bands moving slowly from top to bottom?
That is a beating of the 50Hz coming from the power line and the 60Hz display frequency sent to the monitor. Probably the power supply was letting some AC through to the DC voltages.
 
Vertical waves like horizonatal bands moving slowly from top to bottom?
That is a beating of the 50Hz coming from the power line and the 60Hz display frequency sent to the monitor. Probably the power supply was letting some AC through to the DC voltages.
Yes, that sounds like it :)
 
Hello. I tried a new adjustable psu and the problem remains. I guess that my lcd screens are not displaying the image properly or the pcbs were damaged by using the previous psu units.

These are pics taken with iphone, but you can see the problem with the shadows sprites and glitch with the explosions. These are from strikes 1945, but raiden fighters and guerrilla wars have similar problems with the shadow sprites.
 

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Hmmm, this doesn't look like a power supply issue. The AC filtering bands I was referring to look like something similar to this.
Say, are you using a supergun? And what kind of monitor do you have? CRT or LCD?
 
Looks like an issue to way your LCD handles 240p content.
Can you test your setup on a CRT, issue should be resolved I think.

If so and you want to keep using the LCD, get a decent scaler :)
 
Hmmm, this doesn't look like a power supply issue. The AC filtering bands I was referring to look like something similar to this.
Say, are you using a supergun? And what kind of monitor do you have? CRT or LCD?
Yes. I got it about the AC filtering.
Yes. I'm using a Mak Strike. It does not seem to have any scaler on it.
I'm using LCD screens. I don't have a CRT to test my setup.

Looks like an issue to way your LCD handles 240p content.
Can you test your setup on a CRT, issue should be resolved I think.

If so and you want to keep using the LCD, get a decent scaler :)
No. I cannot test it on a CRT.
Yes, I bought a scaler. it's coming from china.

Thanks for you help. I thought LCD handle these images better, but it seems it's not the case.
 
It is quite likely that either the scaler you bought or the one in the LCD monitor are to blame.
The hardware in your monitor is probably trying to deinterlace your signal while it shouldn't.
Is your signal coming into the monitor through VGA or through scart/component?

EDIT: obtw... LCDs all have scalers inside, and this sucks. Arcades are best viewed on CRTs with a wide vertical frequency range.
 
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