PS2 RGB 220uf caps, still too damn dark.

[ClayStation2]

Tried a couple different 220uf caps, and still, the picture is just too dark. What will hapen if I tried, say, 470uf caps there? 1000uf caps?
What can I do to fix this effect, and what can I avoid doing to blow the thing up? How much here is too much?

[RGB32E]

What monitor are you using?  Adding caps (of any value) will not help on certain monitors.   

[jepjepjep]

I'm having this problem as well.  I built a LM1881 circuit for the sync and the picture is clear, but the colors are too dark no matter how much contrast I have on my monitor adjustments.  I have a 220uF cap and 100Ohm resister on each RGB line.

What do the cap and resistor do to the signal?  If I increase the resistor values will that improve the strength of the colors?

I have a New Astro City cabinet with a Nanao monitor.

[RGB32E]

I'm having this problem as well.  I built a LM1881 circuit for the sync and the picture is clear, but the colors are too dark no matter how much contrast I have on my monitor adjustments.  I have a 220uF cap and 100Ohm resister on each RGB line.

What do the cap and resistor do to the signal?  If I increase the resistor values will that improve the strength of the colors?

I have a New Astro City cabinet with a Nanao monitor.

LOL!!!  The higher resistor value (resistor in series), the darker the image will be!  If you're taking RGB from a Playstation 1 or 2, you "might" need capacitors in series on the red, green, and blue lines.  However, with RGB from a playstation you should never add resistors!  Arcade monitors are built to accept much higher voltage RGB signals (from arcade boards), so adding any resistors will cause a dimmer image on your monitor!  Even after removing the resistors, the image might still be on the dark side.

But try removing the 100ohm resistors and see what happens.

[jepjepjep]

I removed the resistors and it did improve the picture.  I also removed the capacitors as well.  The picture is still too dim though, even with all of the gains turned up on the monitor.  It seems I'll need to get some sort of video amp then?

[RGB32E]

I removed the resistors and it did improve the picture.  I also removed the capacitors as well.  The picture is still too dim though, even with all of the gains turned up on the monitor.  It seems I'll need to get some sort of video amp then?

Using some sort of video amp would be one route.  There are many designs out there to choose from and assemble.  However, if you'd like to just purchase something for not too much money, I'd suggest an Extron unit (off of ebay).  The RGB interfaces and Peaking Amplifiers do a good job of amplifying.  I have an Extron PA 250 and I believe this type of unit would work well for you application, as it can "double" the signal strength.  It's intended for driving long cable runs, but in a scenario such as this, should work fine.
http://www.extron.com/product/product.aspx?id=pa250

Have you checked the manual for your monitor?  Perhaps there could be some sort of input level switch for standard RGB levels.    If so, you wouldn't need a video amp.  I'd also imagine that removing a resistor or two from the monitor's input board would also help correct the levels for the playstation, but would make arcade boards too bright.

[jepjepjep]

Thanks for the replies RGB32E.  Do you think if I install the capacitors without any resistors this will help brighten the picture?

Using some sort of video amp would be one route.  There are many designs out there to choose from and assemble.  However, if you'd like to just purchase something for not too much money, I'd suggest an Extron unit (off of ebay).  The RGB interfaces and Peaking Amplifiers do a good job of amplifying.  I have an Extron PA 250 and I believe this type of unit would work well for you application, as it can "double" the signal strength.  It's intended for driving long cable runs, but in a scenario such as this, should work fine.
http://www.extron.com/product/product.aspx?id=pa250

Have you checked the manual for your monitor?  Perhaps there could be some sort of input level switch for standard RGB levels.    If so, you wouldn't need a video amp.  I'd also imagine that removing a resistor or two from the monitor's input board would also help correct the levels for the playstation, but would make arcade boards too bright.

Unfortunately I can't find too much detailed info on the monitor itself, only a service manual for the New Astro City cabinet.

I looked at the page for the Extron unit and I'm not sure if it will provide enough amplification.  The specs for the PA250 show an output range of 0.3 to 1.5 Vpp for analog signals.  While this may be enough considering the input is 0.7Vpp, I think most arcade boards output 3-5 Vpp.


As a followup, I found some extra pots on the monitor daughter board that enabled a deeper setting for the colors.  The picture looks very good after some tweaking although the Extron unit may still be a good route to go.