VGA box question (with rewarding picture)
-
- DCEmu Fast Newbie
- Posts: 21
- https://www.artistsworkshop.eu/meble-kuchenne-na-wymiar-warszawa-gdzie-zamowic/
- Joined: Sat Dec 24, 2005 9:40 am
- Has thanked: 0
- Been thanked: 0
VGA box question (with rewarding picture)
I finnished up my snes mods a few months ago, and i recently found the VGA box for the dreamcast through hack a day. I knew they existed but never realy looked into em. Since i started looking for more information i stumbled accros many projects and mods, most of wich will probably be made into my dreamcast. I just have to steal it back from my brother now.
I just had a question for those of you who made the vga box, what ratings did you use for the signal and ground isolation caps (volatage), and what diodes where used for the horzontal and vertical ground refrence points? I was just going to use 1/4W resistors, if thats a problem (which i dont think it is) please tell me.
And for your time, my snes.
more of my recent projects here: http://flickr.com/photos/bbasile/sets/1085901/
I just had a question for those of you who made the vga box, what ratings did you use for the signal and ground isolation caps (volatage), and what diodes where used for the horzontal and vertical ground refrence points? I was just going to use 1/4W resistors, if thats a problem (which i dont think it is) please tell me.
And for your time, my snes.
more of my recent projects here: http://flickr.com/photos/bbasile/sets/1085901/
I used 220uF 10V for the RGB caps, but ive used 16V in others that worked okay. I wrote a tutorial in the dcemu.co.uk forums that may be useful to you.
Orange_Ribbon wrote:It is also the reason why you can't wear tight pants. Damn anal warts.
Millenium Falcon Dreamcast
-
- DCEmu Fast Newbie
- Posts: 21
- Joined: Sat Dec 24, 2005 9:40 am
- Has thanked: 0
- Been thanked: 0
sorry it took so long to reply, best buy has my computer right now. Thanks for the info about the VGA box. As for the clock, start here: http://www.electricstuff.co.uk/nixclock.html. He has all the info you realy need.
-
- DCEmu Fast Newbie
- Posts: 21
- Joined: Sat Dec 24, 2005 9:40 am
- Has thanked: 0
- Been thanked: 0
I had another question for those who have made the VGA boxes. THe schematic on devcast has a 74HCT244; and as far as i can tell it just processes the horzontal and vertical synchronization signals. I saw another that forwent the IC entirely. Is the IC needed, and is there any benifit/loss from its usage?
the thing is u don't really need the ic chip here ptr.exe made a more simple circuit/guide, this is the one i'm going to do, mostly because it's smaller...
Feel it, Don't think
-
- DCEmu Fast Newbie
- Posts: 21
- Joined: Sat Dec 24, 2005 9:40 am
- Has thanked: 0
- Been thanked: 0
This is probably another stupid question (especialy coming from someone who is studying to be an electrical engineer) but all the caps i canabalized are electrolytic and the schematics dont mention polarity; does it matter? Ive noticed in pictures of other vga boxes that they use the same kind of caps, but they never mrntion the orientation.
-
- DCEmu Fast Newbie
- Posts: 21
- Joined: Sat Dec 24, 2005 9:40 am
- Has thanked: 0
- Been thanked: 0
I finaly got all my parts in for my VGA box, got it built, but when i connect it to my monitor andpower up, all i get its a black screen. I had the caps like semicolo said and it just flashed the noinput sign,and then switched the polarity and then it was jsut blank. ANyone encounter a simminarl problem in the past that can help?
-
- DCEmu Newbie
- Posts: 3
- Joined: Tue Feb 14, 2006 6:37 am
- Has thanked: 0
- Been thanked: 0
Just for the record, I just finished my Internal VGA Mod using the diagram by ptr.exe (without the IC) and it works just fine. If anybody else wants to make it here are the things I used:
For the caps I used 16V 220uF caps, 4.7K and 150 Ohm resistors. I just used 2 normal diodes.
Some pointers (and DOH's from me ^^):
If u use a VGA conector wich is fitted through the top half of the dc, make sure it is in place before you solder it to your circuit ( ). (same with the switch)
For the switch, ptr.exe's diagram does not show that the 2 "VGA selects" should NOT be solder together (as in the diagram), if they connect VGA mode is engaged, so if you solder them together your normal AV out will not work, even if you flip the swith.
Make sure u solder the wires to the right points on the mainboard! Just as prt.exe I soldered it on the back but I ( again) misplaced two wires because I counted wrong! Check Check and Check again!
For the caps I used 16V 220uF caps, 4.7K and 150 Ohm resistors. I just used 2 normal diodes.
Some pointers (and DOH's from me ^^):
If u use a VGA conector wich is fitted through the top half of the dc, make sure it is in place before you solder it to your circuit ( ). (same with the switch)
For the switch, ptr.exe's diagram does not show that the 2 "VGA selects" should NOT be solder together (as in the diagram), if they connect VGA mode is engaged, so if you solder them together your normal AV out will not work, even if you flip the swith.
Make sure u solder the wires to the right points on the mainboard! Just as prt.exe I soldered it on the back but I ( again) misplaced two wires because I counted wrong! Check Check and Check again!