Unstablewarpfield Posted February 27, 2017 Share Posted February 27, 2017 Hi! I was in doubt whether to ask my question in this topic or to create my own. Since mine is PAL related I decided to go with a seperate topic. I used the schematics in previously mentioned topic to create my own version of them for a PAL system. It's basically a copy and I don't think the differ very much but I am in doubt whether the inputs are connected correctly. I used these PAL schematics to figure out the connections. What do you guys think... did I get the inputs right? Quote Link to comment Share on other sites More sharing options...
+grips03 Posted February 27, 2017 Share Posted February 27, 2017 I used the Odyssey 2 rgb pcb I made on Videopac G7000 and it works fine. Connections are at IC679 (612160). IC679 (Videopac) and IC1 (Odyssey 2) have same pinout. You should have made zero changes. Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted February 28, 2017 Author Share Posted February 28, 2017 Thanks grips03! I'll go with that. So far, this is what I came up with in Eagle. Like with my Intellivision mod... No experience whatsoever in creating pcb's so I guess I am violating many rules again. We'll see what it does... Quote Link to comment Share on other sites More sharing options...
+grips03 Posted February 28, 2017 Share Posted February 28, 2017 If you want the board I made let me know. Price is $20 + shipping. Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted March 29, 2017 Author Share Posted March 29, 2017 (edited) Finally received my pcb design from China last weekend! So much better then my own etched board!!! Really impressed for the 10 euro's it cost me. Had to wait a couple of days for the components to arrive and soldered everything together. I kept getting some weird interference which i traced back to the two blank signals. I left the signal from leg 34 on the 8048 completely off and connected leg 9 of the pal encoder to the corresponding pad on my board and voila... it worked. Basically what you said in your topic grips03... Everything connects to the palencoder chip, with exception of the audio ofcourse. I do get some slight interference in the video signal that seems to be connected to the sounds playing, so I guess a seperate audio connection, or a better shielded cable is what I need. For now... I enjoy the awsome video quality that my G7000 now offers! Edited March 29, 2017 by Unstablewarpfield 1 Quote Link to comment Share on other sites More sharing options...
+grips03 Posted March 29, 2017 Share Posted March 29, 2017 I do get some slight interference in the video signal that seems to be connected to the sounds playing, so I guess a seperate audio connection, or a better shielded cable is what I need. For now... I enjoy the awsome video quality that my G7000 now offers! take a look at: http://videopac.nl/forum/index.php?topic=2873.0 Is that the issue you see? Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted March 29, 2017 Author Share Posted March 29, 2017 Thanks Grips. I just took a look. I am not seeing the dots you describe there in your post. (playing through an xrgb mini on a samsung led tv... dunno if that has anything to do with it.) What I see is clearly linked to the sound. As soon as certain sounds pop up the edges of the pixels get a bit "wave-like" for a split second. It is not very noticable and like this it is defenately very playable. I know that my scart cable is really bad. (as in... unshielded) I might wire my din plug like my neo geo so that I can use that cable. Either that, or seperate sound RCA's. Quote Link to comment Share on other sites More sharing options...
+grips03 Posted March 29, 2017 Share Posted March 29, 2017 Thanks Grips. I just took a look. I am not seeing the dots you describe there in your post. (playing through an xrgb mini on a samsung led tv... dunno if that has anything to do with it.) What I see is clearly linked to the sound. As soon as certain sounds pop up the edges of the pixels get a bit "wave-like" for a split second. It is not very noticable and like this it is defenately very playable. I know that my scart cable is really bad. (as in... unshielded) I might wire my din plug like my neo geo so that I can use that cable. Either that, or seperate sound RCA's. Ah ok, I don't have that issue. Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted April 28, 2017 Author Share Posted April 28, 2017 (edited) Just getting back to my videopac problem a bit. My neo geo cable improved the problem a little, but the problem still persists. I took a short video of the problem to see if some of you wizzards here can identify the problem. If you look careful you'll see the edges of the pixels move as soon as some sound pops in. It looks like interference to me so I'm thinking to go with a scart cable that has individually shielded wires. Edited April 28, 2017 by Unstablewarpfield Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted May 3, 2017 Author Share Posted May 3, 2017 Allright... I tested a scart cable with individually shielded wires and the problem still persists. It seems to be connected to the audio for sure. When I start up Spin out (where the audio is always present when you race) the jittery edges occur again, especially when I crash the car and the higher pitched sounds come in. The next thing I could do is disconnect the audio wire from the motherboard (8245 pin 27 I believe) so no audio is coming into the rgb board and see what that does to the problem. If it still occurs... I have no idea as to what could be causing this. I am running this through the xrgb mini on a samsung tv, don't know if that could have something to do with it. Could it be the audio signal coming out of the rgb board too high? Could it be the layout of components on the board itself? I don't know... we'll see more after some testing. Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted May 4, 2017 Author Share Posted May 4, 2017 For those who still wonder... after some more careful investigation I found out I am missing the 10 nF capacitor in the audio circuit . I quickly soldered one in and the problem seems to be much less now. (Still present a bit though). I might just leave it at this. It seems to be the best this mod is able to do for the console I have here :-) Quote Link to comment Share on other sites More sharing options...
Unstablewarpfield Posted May 5, 2017 Author Share Posted May 5, 2017 (edited) Ok... I couldn't resist checking up everything one final time because something in the back of my head just told me that I was missing something. I checked the voltages on all the outputs and my sync line had about 2.5 Volts on it, which to me seemed odd. After inspecting the schematics one more time for errors I noticed this: It appears I put R772 before R733 instead of after it. I have no idea as to how this could have happened, but it did. I decided to correct it immediately in my board files and exported another gerber to be made. I guess in a couple of weeks I will know more about whether this fixed the problem. Tbh I am a bit fed up with this mod at this point and I don't feel like ripping out the board and start fooling around with wires. Edited May 5, 2017 by Unstablewarpfield Quote Link to comment Share on other sites More sharing options...
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