A4000 Mediator in Ateo Tower

[johnnybarker]

Pretty unusual time at work but I have been given a week of respite for the Easter holidays so, as some light relief, I thought I would take the time to fit a mediator board to my a4000. I decided to share it in the hope someone would find it interesting. I bought the a4000 a year or so ago and it had already been converted from a desktop model into an Ateo concepts tower.
The reason for installing the mediator was to fit an Apocalypse PPC card and so I could move the ZZ9000 to my a2000. I was keen on fitting the larger mediator (D, not Di) as I didn’t want to lose any Zorro slots or the video slot in case my plans changed again. It also provides more PCI slots than the desktop version which is handy when fitting the Apocalypse card.
The Ateo case is a very odd design as the case stands over 2 feet tall yet for some reason the motherboard has been confined to one small corner like a petulant child. I was not sure if the mediator board would fit and I couldn’t find any measurements on the internet. I decided to just to buy it and see where it left me. If necessary, I thought I could cut a slot in the bottom of the case and fit an American muscle car style power bulge and raise the feet up on stilts. I don’t feel bad about hacking up my case as it was not an original Commodore product and is already a total hack.

Picture 1 -A case like this makes up for my anatomical deficiencies

Picture 2- Original Zorro card layout

Picture 3 -Another view of the original layout of the Zorro cards

Picture 4 -This is the hole before I started interfering with it. You can see how little space there is at the bottom.

I made the new support cage for the PCI slots out of metal I salvaged from a fire damaged treadmill.

I cut the box section lengthways to make angle pieces and stuck them together with the welder.

Picture 5 and 6- I ran out of Argon near the end which is my excuse for at least some of the dodgy welding.

Picture 7- I then used the grinder to cut out sections for the PCI cards to stay in place. Everyone likes a bit of grinding.

Picture- 8 At this point I got distracted when I decided to make a grappling hook.

[johnnybarker]

Picture 9 Back to the task at hand I decided to see if the new support bracket fitted before irreversibly ruining my case.

Picture 10- I had some help with the heavy lifting.

Picture 11 It actually fitted which is usual the first time.

Before refitting the Mediator board I covered the back in clear plastic. I used some overhead projector transparencies which for some reason I don’t seem to require very often these days.

Picture 12- For some reason I seem to have a well-stocked PCI modem section in my cupboard. I used a few as templates while drilling the holes for the screws to secure the cards. Hardest bit was finding enough suitable screws and a tap which fitted the threads.

Picture 13- I used an electromagnet to catch the swarf while drilling. Everone likes a bit of drilling.

Picture 14- Here are some of the components before fitting. I was originally hoping to use the PCI card in the photo cage I took from an old server but unfortunately the spacing between cards was different.

While testing the setup I had problems with my mouse which would crash the system every time I double clicked (it was fine with the keyboard control). I suspected the CIA timing. I had previously had this problem before and fixed it by replacing CIA-A. While I was swapping it over quite a few of the pads lifted and I need to do some fairly extensive repair work to the board. It worked for a while but the problem came back. I decided to do it again and this time make a better job of it.

Picture 15 is my previous shady repair. It was taken before I cleaned all the flux off.

Picture 16 - Looks much better this time and it works as well which is always a bonus.

[johnnybarker]

I bought a voodoo 3 recently but could not fit it as I am still having some bother with it. When it arrived, it was missing an electrolytic cap, two caps were dented and one of the SMD caps was broken. It also looked it had been stored in the ocean for bit. I recapped it and replaced the missing one (had to guess the value) and at one point is was working fine in my Pentium 233. After cleaning the board further to get all the extensive corrosion off it I must have knocked off another one of the SMD caps (probably because the joints were so bad) and owing to my poor eyesight I can’t find it. I tried employing the services of a young child with better eyes but he quickly got bored and wandered off. I have tried fitting the commonest value caps which I took from one of the spare modems but it is still not working. I will need to try and find another identical board to desolder the cap and measure the value. If anyone knows the value of this capacitor (c91 )as marked on picture 17 please let me know! I think it is one of the later voodoo revision boards.

For now though I am pretty happy overall with the results and just need to find time to set up the software for the PPC card. The last 2 pictures show the final setup (for now at least).

[indigolemon]

Nice work! Lot of effort went in there, glad it's all coming together for you

[johnnybarker]

Thanks. If any shops ever open I may spray it with a bit of zinc paint to make it look a bit neater. The final finish was never my strong point though.

Hopefully bring it down to the next meet when all this is over.

[indigolemon]

Ace, look forward to seeing it

[Valken]

You know if you modify this and put it into a modern clear panel case with Amiga touches it would look even better. Looking forward to it.

[johnnybarker]

I have loads of perspex kicking about from an amplifier/DAC project so I may try and look it out and see if I could make something out of it. I have to confess though, I have bit of a soft spot for beige!