Upgrades on Upgrades

I’ve taken a little timeout this weekend to play with my Amiga 1200 Tower. Recently I got a very cool Apollo 1260 Accelerator card with a 80Mhz clocked Freescale 68060 CPU. One downside to the A1260 over the Blizzard line of cards was that they only shipped with a single RAM socket, limiting memory to just 32mb. This is still fine for most setups, but I always like to extract the max potential when possible.

The reason for this limitation was to allow the card to fit correctly in the original A1200 wedge case. A mounting point is present on the card for an additional 72 pin SIMM socket. After I tracked one down with the help of a fellow Amibay member, it was very easy to install. Now I have 64mb of ram with a pair of matching 32mb simms.

I also got to install the Elbox FastATA MkV controller that arrived recently. Replacing my original MK1 16bit version gives a big speed increase to HDD access. I’ll do some benchmarks later..
More to come soon.

A1200 Motherboard Repairs (part 4)

Still looking at the 1.D.1 board with the bad capacitors and missing IDE connection.

I managed to clean up the IDE connector as you can see below. A little flux and the solder pump did the job. I also removed and replaced all the original capacitors and replaced with new ones. The board cleaned up very well.

I sourced the replacement IDE connector from AmigaKit. Installation was very easy on a clean board. Just slot it in and apply a little liquid flux to the solder point. Then its just a matter of making sure not to apply too much solder. Results look good to me.

When I finished cleaning up the board, I connected a 4Gb CF hard drive and boot it up. Loaded Workbench first time.

Another board fully restored. So that only leaves the one with the video color problem…..

A1200 Motherboard Repairs (part 3)

Finally got chance to take a look at another couple of A1200 boards.

Firstly a version 1.D.4 that looked to be in good cosmetic condition. This board booted up and passed all my tests so far. No work needed. Happy days!

Next was an older 1.D.1 and it wasn’t in such good shape.
I hooked it up and couldn’t get it to boot. After hunting round the board I found it was missing a smd resistor (R591C) next to the CPU. It looked like it had been knocked off at some point. Replaced the resistor and it Boots!

That’s it for the easy part of this particular board. It was clear to see it was missing its IDE connector. I do seem to remember when I got this board (10 years) ago, that someone had soldered an IDE cable directly to the board, and I quickly removed it. After that it went to storage and I didn’t look at it again. The connector area was a mess, most of the caps in that area also look very bad. I can hardly believe it still works. C239 is even starting to split.

So I plan to replace ALL the Caps, and fully unsolder and clean the IDE area. Then replace with a new IDE header. I may have to repair some of the motherboard tracks that look heat damaged.

A1200 Motherboard Repairs (part 2)

Lets take a look at another couple of A1200 boards from the pile.

The first one was working right away, it was just missing its mouse port. With it being a rev. 1.D.4, the mouse port is on a ribbon cable from a pin header which was missing. All I needed to do was clean up the board and solder on some new pins. Fixed in 5 minutes. Everything else seems to work; HDD, Floppy, Sound and PCMCIA.

The next board however is proving more challenging…
At fist I couldn’t got it to power up properly. The power LED was on but no other sign of life. I could see that a couple of caps around the power input looked bad so I changed them.

It then powered up but still without an image on the screen. I could tell it booted by only by the floppy drive idle clicking.
Next I tried the composite video output rather than RGB. Now I can see an image, but its badly colored.

So I think this is something to do with the composite output system and the RGB output. But at least the board is working.

Amiga 1200 Motherboard Repairs

I decided it would be a good idea to find a spare motherboard for my A1200 tower or WHDLoad system. I thought I might have one or two in storage that might need attention but should be fixable.

Found 5! (3x version 1.D.4 and 2x 1.D.1)

The first board I selected (v1.D.4) booted up fine with a pair of 3.0 roms. I connected a compatible floppy drive and played some Alien Breed II form 20 minutes or so. Everything seems to be in order but the sound is a bit low.

Next I need to test out the PCMCIA connector and see if Hard Drives work on the IDE port. Changing the capacitors on this and some of the other boards would also be a good move. So far its a good start. The cost of A1200 motherboards has gone up a lot from when I used to buy them for £15-20 each 10 years ago. They regularly sell for £100+. 

Looks like I need more Kickstart Roms and Cap kits.

Amiga 600 Vampire project

I’ve started work on my Amiga 600 in preparation for the arrival of my Vampire 600 accelerator board.
This little board will upgrade the modest A600 to around 100x its original speed and performance. It also adds GFX modes with HDMI and AGA game support to the A600. Can’t wait for this one!

In the meantime I’ve installed Kickstart 3.1 rom and a CF HDD to the stock A600.

If you want to know more about this card then checkout the developers site or Apollo Accelerators
Just a matter of waiting for it now.