Tuesday, July 01, 2014

Amiga Repair and Restoration (Part 4)

Story so far..  Amiga now white but caps gone bad.  Cap kit ordered and fitted, some caps not the same physical size and, for my Rev 1A board I'm one short.

So, I have one capacitor missing.  Having done extensive research (I looked at the pictures over at bigbookofamigahardware.com - yes it is a real site) it seems that the capacitor at C460 is not required.  It only appears in one photo of the Amiga A1200 motherboards - Rev 1B - and even then, a quick google shows that not all 1B's had it anyway.  I can only assume that it is one of those things that has no effect on normal operations if it's removed.

Back to the soldering iron then.  Before:

Missing C407
And after:

C460 moved to C407
So that's it.  We're ready to re-build this thing and switch it on.  But wait I hear you cry.  What about mass storage?  Surely you're not going to re-instate that primitive 3.5 inch hard disk that takes up so much space and requires a huge amount of power?  Well, no.

The nice thing about the A1200 is that it has a standard IDE connector which was originally intended for 2.5inch hard disks.  The bigger 3.5 inch units are compatible (and just about fit in the case) with the correct cable but they aren't ideal.  It would be much nicer if we could just use some sort of solid state drive to reduce power consumption and take up less space inside the case.

Well we can.  For a few quid off ebay you can get a simple adapter that allows you to plug in a memory card.  The most common variety of these actually use Compact Flash memory cards.  They're not quite so ubiquitous as the SD cards but are, apparently, still popular with professional photographers, presumably because there's less chance of losing them if you sneeze.

Anyway, the nice postman delivered this:

Compact Flash, here we come!

As you can see, it's really simple.  A short IDE ribbon cable to the adapter itself that has the memory card inserted.  This particular one has Workbench already installed (along with some useful utilities) so that I don't have to faff around with Install disks.

Goodbye huge hard drive!
Installation was just a case of removing the hard disk and associated 2.5 to 3.5 connector cable and the 'Y' power cable that was plugged into the floppy drive.  I put some insulating tape on the bottom of the adaptor board, just in case.  The new 2.5inch IDE cable was plugged in and the install is complete.

Easy peasy installation
And that really is it.  We're done.  Time to make use of the new case screws that I also bought with the capacitor kit.  But now I can actually do them all up as there isn't a huge 3.5 inch hard drive squashed inside.  Yay!

And here he is, now almost as white as the day he was made with a super low power hard drive and a shiny new set of case screws.  Booted first time and the audio fix works a treat.  Nice.

Restored and ready for another 20 years


I know that some of you may be wondering why on earth I would want to spend all this time and effort on an obsolete computer from the early 90's.  It doesn't even connect to the internet (although it could - that's another story...) and has no USB or anything.  I would ask the same question of why people spend thousands of pounds restoring classic cars.  They're no better than modern cars and, in some cases, significantly worse (dodgy E-type brakes for example) and yet people still treasure these cars.

The Amiga WAS the first 'multimedia' computer ever.  It was a multimedia home computer before the term was even really used and so far ahead of it's time it is easy to wonder what might have been had Commodore (US) had a clue as to what they had on their hands.  The old joke goes (and I will repeat it) that if Commodore marketing were asked to come up with a slogan for KFC the result would be 'Warm Dead Bird'.

From a practical point of view this exercise has been extremely useful.  My antics with soldering surface mount components for example.  There are two basic android tablets in the house and both had developed a problem charging.  From the contorted way that the charging cables had to propped or rolled or leant it was obvious that the charging ports were in trouble.  A few minutes with a guitar pick, half a chopped up bank card and a small screwdriver meant that I was able to confirm that the micro USB ports had separated from the main board due to the solder fracturing (lead free thanks to the EU).

There's not enough sticky tape here.....

Dodgy USB port ahoy!
A couple of hours later I had repaired both tablets, saving a lot of hassle from owners of said tablets and also reducing the risk that it would happen again.

Thanks for reading.