ReAmiga 3000 motherboard is fully built and tested

ReAmiga 1.4 motherboardboard

I had an old Amiga 3000 in my stash that I got in a trade years ago. It was traded to me as fully working but never worked no matter what I did. When the ReAmiga 3000 project became known I wanted to save the broken A3000 by building up a ReAmiga 3000 motherboard with the parts from the broken Amiga 3000.

I did not have the soldering skills 15 years ago to do that, but today is a different time (and maybe I was better off 15 years ago with just one A1200 instead of a fleet of Amiga replicas today lol) – So the broken Amiga 3000, or at least what was left of it has gotten a new lease on its life!

Find out more about the ReAmiga project here.

I have already started soldering in stuff that I should have waited with, as usual it is difficult to wait for the right parts to arrive at the post office before starting the project properly.

So this is how it started out. This time I started off with a motherboard with all passives already mounted which saved a ton of time. Interestingly though, I found one error where the BOM specified a tantal capacitor, a regular ceramic cap was placed instead. It was an easy fix once I found a suitable component to replace it with!

Here is the original Amiga 3000 motherboard which acted as a donor card

The components I used from my broken Amiga 3000 was all the custom chips (more on that later), the special memory chips for the scandoubler and some odd pieces here and there such as the trim pot, power socket, disable switch for the scandoubler and the stacked female 25 pin port.

Most of this stuff can actually be found new. But I usually like to keep some parts from donor Amigas in new builds not just the custom chips for some weird reason.

Believe it or not, I actually used the same KEL connector for the CPU board that was soldered to the broken A3000. It was a painful experience desoldering it as it is soldered with 200 pins to the motherboard.

I also wanted to save the two edge card connectors for the daughterboard, desoldering them was a major hassle since the ground plane is very strong on the A3000. Instead I ordered replacements from AliExpress because they where extremely difficult to desolder.

Chipset gave me a surprise

As is de rigeur when building an Amiga replica, there are always some kind of surprises no matter how much prepping one does.

There are some very expensive chips on the Amiga 3000. First is the Amber chip which is part of the scandoubler/flickerfixer area of the A3000. Then there is the DMAC chip, both chips costs a ton of money to source if replacements are needed.

I did not know if these chips where working before starting the build and I was not prepared to pay 250-450+ euros for replacements if they did not work. Luckily, once I had the board fully built, I can now confirm they are working just fine!

But surprised I was, the Ramsey chip was broken. My ReAmiga 3000 would not start with my original Ramsey chip installed. Luckily I had a NOS Ramsey 07 chip in my stash that worked fine as a replacement.

And as lucky as I was, the same day, I noticed that a Buster 11 was offered for sale on a local website meaning I could skip the Buster 7 I had from the broken A3000. As it was offered on a local trading website I got it muuuch cheaper than from Ebay.

But…. I know what you are thinking, Super DMAC 02 and Ramsey 07, that is a recipe for trouble.

Lets find out if Ramsey 07 plays well with my revision 02 of the Super DMAC. I will just have to find out once system is fully up and running with Workbench installed. Then I will be able to do some stress testing. If problems occur, I will need to track down a Super DMAC replica.

Next steps….

Now all I am waiting for is a replica A3000D case to be available and I will order one in black ASAP. I am also doing a daughter board for it which I will post about later in the year here.

Practice makes you perfect (when building an Amiga motherboard)

Motorola 68030 25Mhz on the A3000D motherboard (ReAmiga 3000 SMC version)

I am working on a ReAmiga 3000 motherboard. I am in no rush to finish it, taking it really slow ordering one set of parts at a time. Last week I got the 68030 so I decided to solder it on the motherboard this weekend. Hopefully I will be able to do a test drive before Q1 is over!