Dragon's Lair Fans - Arcade Lifestyle
General Chat => Technical Area => Topic started by: Muerto on September 03, 2009, 08:14:29 AM
-
Hey..
well, i think this appeals to Bruno, so maby you will guide me?
What to use etc. :)
Michael
-EDIT-
found this pic bruno used in another thread, modified a bit so everyone can undestand it ;) (my french is a bit rusty..)
(http://muerto.superfreehost.org/scart.jpg)
-
is this correct? i always thought pin8 = 5v ?
-
well, seems like youre wrong..:
(http://www.leadsdirect.co.uk/images/technical/scartdiag.gif)
-
maybe its nice to put here a schematic like this, but the for VGA - SCART....
or even better , can you just hook a tv through scart to a standard videocard ???
-
TV for monitors cheapens the machine IMHO - fix the original monitor unless it has awful screen burn
-
Pin 8 should be 12V
Pin 16 should be between 1V and 3V. So 5V is actually too much if you check the SCART standards. To prevent any problems use a resistor of 100 Ohms in serie with that connection.
I've written a pretty extensive story about it here:
http://forum.arcadecontrols.com/index.php?topic=77370.0
-
TV for monitors cheapens the machine IMHO
Why do you think so ? Because the picture would be worse ? That is absolutely not so because we can use the SCART connection for full RGB quality.
It's not that I'm saying throw out all the monitors. Most of the times they can be easily fixed. Plus there's all needed kinds of adjustments, which is not always so with (older) TV's. But if you get TV's like Bruno used, you get the extra deluxe digital set-up menu's which is as good (if not better) than the regular adjustments on a true arcade monitor.
But I agree, I will always try to fix the monitor first. But if (close to) impossible, I use a TV too. Can't see any difference on the outside...
-
ah... good to know. thanks.
-
Well, i have tried several PCB´s now, and i got picture!!! :) - but only in Black/White >:( >:( >:(
what the hell??? am i douing somthing wrong?
-
Yes.
-
ok, thanks!
-
You're welcome ! ;D
-
To be honest, I remember I had the same problem once, but I can't remember what caused it !
-
First I would check the three colors.
Make this test :
1. Remove for example the blue and the red wires... Do you still have a picture?
Yes -> It means that the signal is correct on that wire
2. Remove two others colors ... same question?
If the three colors wires are sending a signal (I think it's the case), I would say your TV cannot fully understand that she have to switch in RGB.
Check the voltage on that specific pin (pin 16, 5V to inject). Note that you can force your TV to switch in RGB by pressing several time the external boutton [->1] on your remote control.
If you get a stable picture, it means that the synchro is fine, don't check that.
If your TV has two scart connectors, only one can understand a RGB signal (most of the time), try two plug on the other connector.
You can also remove the wire that force the TV to switch (pin 8, 12v). On some TV, that make the external channel going mad.
Don't hesitate to try on different TV, you'll be surprised ;) But don't try on modern TV flat screen... because these new tb TV are able to understand the input signal, and if something go wrong (not exactly a precise voltage expected for example), it displays... a black screen :shock: Not easy for investigate of course :roll:
Each time I got problem while using PCB to Scart (or VGA to Scart) connector, I'm doing a mix of these tests ...and guess what... I works ALL the time ;) I've done this more than 20 times, maybe more.
Good luck
-
bruno has got a good point with the second scart
i remember that in one of the 3 connectors of my tv i have color when i use svideo-scart converter (pc to tv)
the other two grayscale.......
-
thanks! - i will solder the 5V later today, fingers crossed!
-
hey, what do you know, +5 helped! (now there´s only some colors missing...) any way to correct this?
does Ground (GND) have somthing to do with that?
(http://muerto.superfreehost.org/arc/color1.jpg)
(http://muerto.superfreehost.org/arc/color2.jpg)
(http://muerto.superfreehost.org/arc/color3.jpg)
(http://muerto.superfreehost.org/arc/color4.jpg)
(http://muerto.superfreehost.org/arc/color5.jpg)
AND..
When i test DK-DKJ-DK3 the screen rolls like crazy (im using a NIN to JAMMA adaptor..)
-
What colors are missing then, I see Red, Green and Blue....
The sync problem > SCART requires composite sync. Not sure if that comes out of that adapter ? Else you'll have to combine H- and V-sync signals.
-
ok, RGB is present on all pictures, but if you see at the clouds on the Wonderboy screen, and the eyes on the Snow bros main screen and top of platforms... there´s somthing wrong...
-
Except the 'WonderBoy in MonsterLand picture', the colors on others games seems to be inverted?!
Maybe you're inverting some colors? Try to swaps the three color wires? (I mean maybe you're sending the blue signal from the board into the green input of the TV for example...)
I've also have similar thing... the 'Brightness?' potentiometer (one of the two pot close to the high voltage, usually in black) was too high, and in some part of the screen, some areas were 'color saturate'...
-
actually bruno, WIM is the closest to be perfect, only some minor issues there...
actually, it´s the white color there´s missing:
-EDIT- or maby youre right, somthin´s inverted!
(http://muerto.superfreehost.org/arc/color4.jpg)
KLOV:
(http://www.klov.com/images/11/118124217039.png)
-
But the top line (score, 1up, 2up) seem to be the right color.....
Sorry I didn't notice earlier, I don't know these games.
Try a test-screen on one of the boards with RGB so you can be sure....
-
this is strange!
When i slap in my Silk Worm PCB, the colors are perfect!... hmmm
Another question:
How do i force the TV to start up on the SCART channel?
-
Another question:
How do i force the TV to start up on the SCART channel?
(http://www.leadsdirect.co.uk/images/technical/scartdiag.gif)
:arrow: 12v in the pin 8 ;)
-
... that was easy! thanks! :)
-
Looking at the images explaining what to connect to which pins on the scart connector - I'm not quite sure how to make a test setup with a TV for my Centipede board.
The pinout is as follows:
http://www.ggdb.com/KB.aspx?c=Coin-Op&s=Arcade&vid=503&kb=44
There are no Red/Green/Blue grounds mentioned in this pinout table. Is it just connecting the RGB and the composite sync from the board and it's a done deal?
Maybe the Video return pin on the board has to be connected somewhere?
I'm sorry to bring up an old post - but it seemed relevant for my question.
-
There are no Red/Green/Blue grounds mentioned in this pinout table. Is it just connecting the RGB and the composite sync from the board and it's a done deal?
No.
Maybe the Video return pin on the board has to be connected somewhere?
Yes, video return = video ground, so connect all three R, G and B grounds together to video return. It is also probably a good idea to connect it to the power supply ground too.
Matteo