Neo Geo AES video output mod

[hokuto29]

hello guys!!!

i have both AES and MVS systems and i see how much better rgb output quality the MVS has,this is what i want to know,

its possible to mod the AES video output to gain same or near quality than MVS?? i saw some models on ebay via component,but you guys have tested anyone???

cheers!

 

[JeepMan82]

Just recently had my AES system modified with component video by Jamma Nation X. I am very pleased with the picture quality over the standard composite cable. Nice clear picture with no blurring on my Samsung LCD TV.

 

[hokuto29]

thanks for answer mate

 

[GohanX]

Do you have RGB scart monitors in Spain? You can do the RGB bypass mod on the home systems with weak RGB and easily make them as good as MVS systems. The mod is easy, no component trickery needed, just a Neo RGB scart cable.

http://www.jamma-nation-x.com/jammax/tutorials.html

 

[NEO-GEO man]

Need to know what revision you have really, the earlier ones have different capacitor and resistor values to the later ones. The 3-6 will need a couple tracks cut on the under side of the board, but the others will all be pretty simple.

 

[Jonny l3lanka]

Was there actually a reason they made the RGB ouput inferior in the later models? Did this somehow compensate for better composite?

 

[NEO-GEO man]

How many times will this get repeated....

Its NOT inferior. All revisions are capable of the same if you put the correct capacitors in there. Every single one has the exact same sharpness provided your display is up to the task.

In my opinion, the 3-5 and 3-6 have the best RGB cause they have the right value capacitors in them. Brighter colours and better black level.

 

[vasilas432]

How many times will this get repeated....

Its NOT inferior. All revisions are capable of the same if you put the correct capacitors in there. Every single one has the exact same sharpness provided your display is up to the task.

In my opinion, the 3-5 and 3-6 have the best RGB cause they have the right value capacitors in them. Brighter colours and better black level.

If you do the mod what are the cons?

 

[NEO-GEO man]

There are no cons. If you have a revision that has the wrong value capacitors and resistors ( 1st through to at least 3-3, but check to see what is fitted ) just replace those with the correct value ( the value recomended by Sony for use with the CXA1145 ) which is 470uF and 75ohm. Earlier machines have got 100uF caps and 68ohm resistors.

Swapping to the value above will brighten up the RGB and improve the overall contrast.

If you have a 3-5 do nothing, they have the right components and their RGB is brilliant. If you have a 3-6 just cut the tracks under the board as specified in the tutorials you can find on here and i think i saw it on the Mmmonkey website.

Just replace the RGB resistors and capacitors with the values they should be, leave the others. 3 caps and 3 resistors will cost you well under $5.

 

[vasilas432]

There are no cons. If you have a revision that has the wrong value capacitors and resistors ( 1st through to at least 3-3, but check to see what is fitted ) just replace those with the correct value ( the value recomended by Sony for use with the CXA1145 ) which is 470uF and 75ohm. Earlier machines have got 100uF caps and 68ohm resistors.

Swapping to the value above will brighten up the RGB and improve the overall contrast.

If you have a 3-5 do nothing, they have the right components and their RGB is brilliant. If you have a 3-6 just cut the tracks under the board as specified in the tutorials you can find on here and i think i saw it on the Mmmonkey website.

Just replace the RGB resistors and capacitors with the values they should be, leave the others. 3 caps and 3 resistors will cost you well under $5.

Mine is 3-3. What should I go and buy? Is there a tutorial to show me where to solder? I am a real newbie!

 

[NEO-GEO man]

You need to open it and see what capacitors are in there first.

 

[vasilas432]

You need to open it and see what capacitors are in there first.

Where are they located? I have opened it where to look?

 

[vasilas432]

I suppose I have lockated them. Which ones do I need to change. You talked about three but I see five each.

 

[Xian Xi]

I suppose I have lockated them. Which ones do I need to change. You talked about three but I see five each.

Check which ones are connected to the RGB output of the encoder. I think it's the three before the last pin on the chip. Check the datasheet.

 

[NEO-GEO man]

On the CXA1145 chip, numbers 21, 22, and 23 are Blue, green, and red in that order.

With the meter on ohm scale ( 200 ohm setting will do if your meter isnt auto ranging ) put one probe to one of the above pins and then test the + side of the capacitors. When youve got the right one, meter should read between 65 and 80 ohms.

Tell you what will be easier though, replace all the 100uF caps there with 470uF caps. Ill get on my computer in a minute and post schematics.

 

[NEO-GEO man]

Righto, here is the schematic diagram of how it SHOULD be all connected, as per Sony recomendations. Dont get too hung up on it all, just note the pins youll be needing to change caps on are in a red box.

Now i thought if i post this, you should be able to work out the value of the installed resistors without testing them or removing them.

 

[vasilas432]

I bought 5 caps 470μ and 5 res 75ohms. I don;t understand the above. If you could tell me in my photo which ones to put out and put the new ones. If you can take my photo and mark on it. If you would like I can post photo of the back of the PCB. I know nothing about reading the above. Thanks a lot man! I will be online in five hours and 30 mins from now!

 

[vasilas432]

I can post pics of the res and caps bought

 

[NEO-GEO man]

Make sure the caps are 16 volt or more. Look on the side of them and in your machine 5 of them will say 100uF 16v, they all need to come out and the 470uF 16v ones go back in their place. Make sure polarity is correct.

 

[NEO-GEO man]

I can post pics of the res and caps bought

Yes do that.

I cant draw on your pic, im using a mobile phone.

 

[vasilas432]

Here they are:

The short leg of the caps is the minus?

 

[vasilas432]

The ones on the PCB are 10v

 

[Xian Xi]

The ones on the PCB are 10v

As long as the rating it the same, 470uf. I usually use at least 6.3v so 16v is fine.

 

[vasilas432]

Which res I need to pull out?
Thank you Xian Xi

 

[Xian Xi]

All 5 x 68ohms and all 5 x 100uf caps.