Neo-Geo Forums  

Go Back   Neo-Geo Forums > General > Tech Support

Reply
 
Thread Tools Display Modes
Old 06-08-2004, 02:46 AM   #1
RockstarRunner
RockstarRunner's Avatar
Hardened Shock Trooper
 
Join Date: Mar 2004
Location: Vantaa
post[field6]
Posts: 427
RGB bypass mod for Neo models 5 to 7

Hey,
Here is some info for anyone wanting to attempt the RGB bypass fix on a model 5 to 7 series NeoGeo.

I would like to point out all technical information was provided by forum member MKL


Bigger image

This picture shows the under side of the Neo mainboard, the corner that is under the A/V connector.
There are 4 connections to make as detailed in the image, one for each R,G,B and another for the true sync.
These connections should be made with an 82ohm resistor between each of the RGB lines(sync line does not require the resistor), as the standard signal strength is too intense for the t.v. to display correctly.
Connections are taken from any of the 7 resistors for a given colour, the points shown in mine are not required, just what I went with.
Note that the bottom plastic shell has an indented vent near the point where you're doing the mod so make sure you're soldering the wires in such a way that you can fit the board back into the shell.
Connections are made to the ferrite beads (the blue things) just before the A/V port pins instead of the A/V port pins themselves, so the signals will be protected from possible RFI/EMI interferences.


Bigger image

Remove the labelled components, that being 3 resistors & 4 capacitors.

After having done this mod, the vertical lines that where present accross the screen are now gone, the colours are vibrant, and the image is sharp and clear.
I highly recommend doing this mod, it made a world of difference to my Neo, serial #333883

Note: resistor order when viwed from the top of the board
01 = 220 (R)
02 = 470 (R)
03 = 3.9k (R)
04 = 2.2k (R)
05 = 1k (R)
06 = 150 (R)
07 = 8.2k (R)
08 = 220 (G)
09 = 470 (G)
10 = 150 (G)
11 = 8.2k (G)
12 = 1k (G)
13 = 3.9k (G)
14 = 2.2k (G)
15 = 3.9k (B)
16 = 2.2k (B)
17 = 1k (B)
18 = 470 (B)
19 = 220 (B)
20 = 150 (B)
21 = 8.2k (B)

Note: After having done this mod, your NeoGeo will no longer display composite out video! only RGB.

If you have any technical questions, not answered here, I recommend contacting MKL, he's the man in this area!
And one last point, only do this if you have a steady hand, those solder points are quite close together.
__________________


You're ghostin' us, motherf***er.
I don't care who you are back in the world.
You give our position one more time,
I'll bleed you, real quiet, and leave you here.
Got that?
RockstarRunner is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 07:16 PM.


Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2010, Jelsoft Enterprises Ltd.