AV-mod for 7800 ProSystem

Started by WERY, August 25, 2011, 03:02:57 AM

Previous topic - Next topic

WERY

I have modified my 7800 system so that I can connect it to an AV output. It works :D :D I did this mod in the spring so it was about time I put it in here

Here I build a new circuitboard for the sound and picture circuits so that they can be connected to the AV jacks that goes to the TV.

The blue cable is soldered to the GND on the mobo. The red one is connected to the GND on the RCA jacks. I also put on some rubberfeet on the other side of the curcuitbaord so I can place in on the mobo without it getting in contact with other circuit's on the mobo.

Here, I connect the sound from the console to the new curcuitboard.The black cable goes to the upper side of the C14 so that I can take out the POKEY sound and connect it to the RCA. The red one is the sound itself from the C10

I had to remove this while soldering the POKEY cable but luckily it only takes 2 screws to remove/put it back.

Here is the whole system with the new AVboard connected to the mobo. However I changed 2 of the cables in this picture, the one that gives 5 V and the video-input.

It may be stupid by Atari to not using AV connection from the beginning but they on the other hand put an AV-modifier hole on the side so the cables can go out that way after put back the RF shield together

The cables gets soldered to the RCA jacks

So it is...

Galaga was the first game to be tested

Picture is a little blured but it looks much better in reality.

The room lacked enough light

I found a new favourite game and that is Robotron 2084

This is the scheme for the videomod(sound not included on it) but the 75 ohms resistor was changed to a 82 ohms since I did not had any 75. It works great any way

Brother of Bros

jamisonai

Why did you do an s-video mod since you have a CRT anyway? Here's a link to my 7800 s-video mod: 

  http://s1182.photobucket.com/albums/x447/jamisonia1/

I followed this guy's mod

http://saundby.com/atari7800mod/7800_vidmod_construction.html

WERY

I did a C-Video mod as it was the easiest way to modify the 7800 according to the guide I looked at. In the first one I saw, they used a custommade circuitboard to get the S-Video signal and I did not know of any other way to get S-Video so I took the easiest C-Video mod I could find and by help of that one, I made this guide


I might try this simplified S-Video mod in future when I get more systems
Brother of Bros