Socketed ColecoVision PCB

[Yurkie]

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.

[+5-11under]

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.

[Yurkie]

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.

[retroillucid]

Nice works Todd!

 

Yep, that's the way to go

[+5-11under]

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.

[Yurkie]

I am going to install my pause button and single jack A/V composite mod and use this as my primary console.

[Yurkie]

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.

[Yurkie]

Nice works Todd!

 

Yep, that's the way to go

 

Thanks J-F.

[Madaracs]

Excellent work!