+Yurkie Posted October 16, 2010 Share Posted October 16, 2010 I decided to install sockets for ICs on a ColecoVision PCB, this will make for easy replacement if a chip fails in the future. I socketed the DRAM (video ram) VDP Sound BIOS (replaced the original with an EPROM, programmed with the fire button intro skip) Octal Buffers (controller chips) CPU I might end up installing sockets for all the ICs, and I am considering replacing the 4116 DRAM which requires +5V, -5V and +12V with the 4516 or 4164 DRAM which requires only +5 volts. Here is a pic. Quote Link to comment Share on other sites More sharing options...
+5-11under Posted October 16, 2010 Share Posted October 16, 2010 I 100% agree with socketing the controller chips, and, if you're replacing them, perhaps the BIOS and RAM chips. Others, especially the logic, Z80, and sound chips seems unecessary, unless you want to test parts, of course. As the years go by, it could become a potential failure point. One of the first "tricks" people learn in repairing old boards is to re-seat all of the socketed parts. Sounds like a lot of work, too. Quote Link to comment Share on other sites More sharing options...
+Yurkie Posted October 16, 2010 Author Share Posted October 16, 2010 I 100% agree with socketing the controller chips, and, if you're replacing them, perhaps the BIOS and RAM chips. Others, especially the logic, Z80, and sound chips seems unecessary, unless you want to test parts, of course. As the years go by, it could become a potential failure point. One of the first "tricks" people learn in repairing old boards is to re-seat all of the socketed parts. Sounds like a lot of work, too. The VDP seems more prone to failure than the DRAM in my experience and since the VDP and the Z80 CPU use the same sockets, I figured what the heck. I probably spent about 6 hours on it. I did the DRAM last and was pleasantly surprised after pulling all 8 ICs and installing sockets, that when I inserted those original DRAM in the sockets and fired it up that it worked and passed the video test. Quote Link to comment Share on other sites More sharing options...
retroillucid Posted October 16, 2010 Share Posted October 16, 2010 Nice works Todd! Yep, that's the way to go Quote Link to comment Share on other sites More sharing options...
+5-11under Posted October 16, 2010 Share Posted October 16, 2010 My main CV has recently developed a DRAM issue, that only shows up on some games, and sporadically fails Atarimax's video test. Good times ahead, one of these days. Quote Link to comment Share on other sites More sharing options...
+Yurkie Posted October 16, 2010 Author Share Posted October 16, 2010 I am going to install my pause button and single jack A/V composite mod and use this as my primary console. Quote Link to comment Share on other sites More sharing options...
+Yurkie Posted October 16, 2010 Author Share Posted October 16, 2010 My main CV has recently developed a DRAM issue, that only shows up on some games, and sporadically fails Atarimax's video test. Good times ahead, one of these days. Occasionally if the power jack is loose that can cause DRAM test failure. Quote Link to comment Share on other sites More sharing options...
+Yurkie Posted October 16, 2010 Author Share Posted October 16, 2010 Nice works Todd! Yep, that's the way to go Thanks J-F. Quote Link to comment Share on other sites More sharing options...
Madaracs Posted October 19, 2010 Share Posted October 19, 2010 Excellent work! Quote Link to comment Share on other sites More sharing options...
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