ScuzzBlog: Diaries February 2021
Entry 25th February 2021: Post 1: Amiga 2000 - Dead in the water NOT !!
Amiga 2000 - Dead in the water NOT !!
Some while back now I did a feature on an A2000 that I had stored
in its box with a system failure. Basically she was dead in the
water and displaying a black screen and no boot. This I believe
was my first A2000 and first battery removal. I sense I did not
remove the PSU/floppy cradle and whilst removing the battery I
did not clean up properly and missed the CPU legs. Over the years
the legs have corroded and failed.
Today I decided to take the A2000 out of the box and have another
look. Not an easy task as the box was behind a stack of tubs. But
I struggled and eventually extracted the Amiga 2000.
Sure enough the computer wasn't displaying anything on the screen.
I had a fiddle with the CPU and then got a white screen. Then a
broken white, and then a red and then a green... BINGO ! CPU failure.
So I knew what I was looking for.
I had resisted taking out the CPU cus in the past I have completely
found broken legs on the chip and broken socket receivers. But she
wasn't working so I just jumped in. Man was the socket a mess. Took
me a good while to clean up and I wasn't able to remove all the
green but I scraped out most of it. I used alcohol and cocktail
sticks. For the chip legs I even sanded the metal to try and bring
the shine back.
What I found was the last four spring metal tangs inside the socket
were less than rigid. The end one looks broken. However I had kinda
cleaned off enough of the receiving connector to have half a chance
of making a sound contact.
Failed !! Nothing. Just a black screen. Time to spread those legs.
This time I expanded the legs on the CPU chip as wide as I could and
then placed the right hand legs in tight against the socket. Then
I gently eased the left hand legs in, placing pressure on the right
hand set to allow the legs to drop. It's a tricky technique but the
aim is to get the legs springing out and forming a tight grip on
the socket connectors.
AND THAT WORKED... Incredible. Multiple boots and disk insertions
and she fired up every single time.
I used the disk that I had been using on the A3000 and discovered a
rogue program on the disk called SCION a genealogy program. Also
the loading of the SHELL threw up a load of garbled letters. Sadly
the keyboard appears to have lost the delete function and some of
the letters stick. I used 1.3 but those stuck keys persisted so my
usual comment about the date isn't quite right. But you get the idea.
I dug out another 2.04 disk but someone had customised it to change
the palette. There was no red visible. So I fired up R-Type II to
check and all the colours were working. She was working way better
than on the A3000.
And so the computer is working. Irrespective of the problem, part
of the retro challenge, when you hit issues, is to identify the
problem. It is very frustrating having a computer with a problem
that you cannot determine. So knowing what is wrong just makes life
a whole load easier. In this case someone would need to de-solder
and replace the CPU socket. And so the label on the computer
records an issue but also states the date the computer was last
working. So when I put her away today I could rest easy....
She's Alive !!!!
Amiga 2000 - Dead in the water NOT !!
Happy Days
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