Amigo - A sidecar for the A600/A1200
Why?
I had some A600 in my Amiga-Life. Most of them, broken. The usual problem, dried/leaked capacitors on the motherboard. The A600 is a nice replacement for the A500, since it can run Kickstart 1.3 with my simple Kick-switch-start® and has a PCMCIA port which I can use compactflash cards, or network adaptors, and an IDE port. A real nice computer for everything Amiga.
I always wanted an A1200. A good fella from USA gave me one as a gift (thanks guy, you know who you are) and I'm waiting for that to arrive. While that, a friend of mine brought me an A1200 which was in the scrapyard. No mouse, power supply (PSU) or anything. I though "Time to hack!"
The Amiga every man wants to have
The A1200 is a great puter, everything an Amiga should be. But the small size makes it harder to put a normal 3 1/2" HD inside. So I have to use notebook-sized HDs (2 1/2") which are in Brazil prohibitively (thanks Scuzz! I'll learn to spell it someday) expensive. Also, a friend of mine (Rudolph Gullich) showed me an A1200 with a DVD drive. My gears started to run.
The question is: What are the problems of the A1200?
- Lack of internal space for a normal-sized hard-disk
- Lack of internal space for a DVD-ROM (no, that A500 case hack is not good. Nor a tower)
- Lack of internal space for a second drive (ever tried to copy a disk on XCOPY without two drives?)
- Lack of juice in the PSU, making all the system unstable
- Lack of enough thickness of wire in the power connector, making the use of internal peripherals in A1200 at least dangerous
- Lack of space for a scandoubler
So I created AMIGO, a Sidecar for the A600/A1200! :oD
It contains:
- DVD-ROM drive
- 3 1/2" HD in a removable floppy bay
- HUGE power supply (AT PSU with amiga cable)
- Second floppy drive
- Enough space to host a Zip drive (IDE or Parallel)
- Stereo Amplifier (still not done)
- Scandoubler (Amiga -> VGA video conversion)
- Space to house a genlock (I have a rocgen stored somewhere...)
All of this in a cutted AT case :o)
How I did it?
First of all, I got a pretty common PC cabinet
If you pay attention to the bottom side of this cabinet, you will see that the top is an entire piece in U shape, while the bottom "closes" the "U". I drilled the rivets to loose the bottom. Cut half of it, and we got this:
The cuts were done 1.5cm below the mark, to bend the metal to the inside and create the place where the new rivets will go. See the photos and you'll understand
So I cut the front mask, a little bigger to cover the bottom of the cabinet
And also cut the cover of the cabinet, in the right size. The best method is turning the cover upside down, putting the finished body of the cabinet and drawing a line on the cover beyond the bottom of it. You can use a scrollsaw to cut it, if you protect the bottom of the scrollsaw with a piece of wood or plastic (not to scratch the cover of the cabinet) and use a proper metal saw
Also, in the front of the cabinet, is good measure to take a little piece of metal to secure better the front mask. It uses 4 screws to hold it on place. Since you cutted it in half, probably you will have only 2 screws holding it on place
This is the final result, before installing the peripherals
PART 2 - The Amiga
Now we are going to mess with the Amiga! :oD Do I need to say that if you are not handy with a soldering iron, you should not do this part? :o)
The amiga lacks an external IDE port, so we will "create" one.
First, get one old motherboard and take out the two IDE connectors. Of course, you can buy new. But try to find these connectors here in Brazil. And of course, I have some dead motherboards around, so why spend uneeded money?
These are the two connectors. You will also need some perforboard for doing that
You will solder the two connectors in a strip of perfoboard. It will make soldering easier, and better to screw the connectors in place
I'm showing in this photo the proper way to be sure all the pins are in the right height: Plug an IDE cable on the connector, and put it on perfoboard. So use the back of the screwdriver to draw all the pins to the inside of the IDE connector. They will be all in the same height. So it is just soldering.
And here is the final result - Two identical strips with the connectors.
Since we are on a cheap, get an old IDE cable and separe, strip and tin all the 40 wires
Solder each one of them in one of the IDE connectors. Dunno how to know where is the pin 1? Look at the IDE connector, where the red wire is. You will see a small arrow. That is the pin1. So you will solder the ODD wires in the line of the pin1 and the EVEN wires in the other line.
CHECK EVERYTHING
- The pinout is right?
- Any shorts?
- Any small blob of solder or strain of wire shorting anything?
- Any loose wire?
Ok, this is the sidecar-side of the cable. Now we are going to do the Amiga side of the cable
First, cut a slot on the side of the A1200 cabinet. The better place for doing that is on the top left, remember it will be screwed so you don't need to worry about taking the cover off for a cleanup (mine needs that before assembling)
Test-fit your cut to see if the connector fits well
See how things will be inside. You can use spacers to put the connector flush with the A1200 surface, or put it "sticking the nose out". I prefer the later
And this is how I did mine
Now, connect everything on the Amiga to see if it is working
It is a shame the former owner of this A1200 did this mess on the board. It will be more expensive to fix than to leave this way. So we will (painfully) leave this way
The RIGHT way would be:
- Take one piece of flat cable with a IDC-40 connector on one side
- Separe, tin and solder all wires on the connector board
- Get a 44-to-40 IDE adapter
- Plug the cable into the IDE adapter
Since the a$$h0le who owned it went to the gambiarra way, we will have only to solder the connector inside.
Ok, now everything is ready for a test
We have to cut the sidecar to do a RIGHT window for the IDE cable.
Everything is working? Great! Time for the power supply!
Hack-a-PSU
Ok, the original A1200 PSU is too weak. Beyond that, this A1200 had NO power supply, so we had to find a solution:
Get a dead brick cable, secure it on sidecar and solder the wires on the PC PSU.
Voltage
Wire color in PC cable
Wire color in Amiga cable
+5
Red
Red
+12
Yellow
Brown
-12
Blue
White
GND
Black
Black
That is all you need. A hefty PC Power supply now feeds your Amiga. Since you don't need to power the internal peripherals (HD, CD et al) you leave more juice for the accelerator, which draws a lot of power.
A small remark: Did you see in the photo how THIN the wires going to Amiga are?!? This is not good if you use power-hungry internal accessories (HDs as an example) because not only the tracks on the Amiga Motherboard get stressed with so much current, but also these thin wires are not capable to carry much current. When current rises in a small wire, resistence lowers the voltage and adds more heat to the conductor. This is not good. I'd towerize the A1200 but I love it in its form. So I'll leave as it is. I'll do that in the A600 instead, since its keyboard is dead (not to say a bad word) and I'll have to adapt an A500 or A2000 keyboard anyway.
The internal scandoubler will be added later, I want to play a bit before doing that, I'm crazy to see this A1200 working :o)
Well, this is the final result
As you can see, this is not a work of art, but it is very functional, and I don't loose the A1200. Also, the external IDE port makes it very portable, even because I can use the A600 with that too!
Hope you like the photos. Any comentaries can be directed to alexandre (you know what) tabalabs.com.br