Restoring an A3020

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arkiruthis
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Restoring an A3020

Post by arkiruthis »

I recently acquired an A3020 (one of my retro life goals fulfilled :D ). Clearly a schools model, as it has the HCCS podule (and faint marker pen residue on top stating an academy). The keys are were very yellow and the case quite dirty, but the lack of visible rust around the rear ports gave me a little hope that the internals were okay.

FIRST BOOT
Starting up the machine.
Starting up the machine.

On first starting the machine (VGA connection), the lights came on, but no display (which I initially considered might be a VGA mode issue). But on powering up again I held down Delete and this time it booted into the OS. This was the first indicator that the battery was corroded, leaving me to wonder how bad. :|

Battery Damage (BEFORE)
Battery Damage (BEFORE)
Battery Area (AFTER)
Battery Area (AFTER)


Turns out pretty bad! It was a little awkward to get to (and annoyingly I didn't realise I'd scratched the PCB as well getting it out). Following the usual advice I took distilled vinegar and a toothbrush and treated the area until the fizzing stopped after repeated treatments. I then cleaned the vinegar off and finished up with a general IPA clean of the PCB. I suspect the nearest port is probably done for, but by and large the other components seem to be in fairly good condition... except...

BAD CAPS
Bad Caps!
Bad Caps!
Whilst doing a Q-tip clean with IPA around the components, a couple of the Capacitors on C88 and C90 have come loose. (and my suspicions about C93 - indicated with arrow, turned out true also as that also came right off with little pressure).

It's difficult to tell at the moment visually whether the pads are destroyed, but I have a good friend who is familiar with recapping who believes it may still be possible to do some repairs if they have indeed come off.

I'm currently making an inventory of the replacements required and will hire him to do the work as I'm more software than hardware savvy.

PLANS (Assuming Refurb goes well)
  • Good Clean (in progress) but no retr0briting (I rather like the yellowed look).
  • Install CR2032 (with diode) to restore CMOS functionality.
  • Install a CF Card on the IDE port as a HDD.
  • Upgrade the RAM (currently slots are empty)
SERIAL ISSUES
Serial Number
Serial Number
The Acorn RAM upgrade manual states there are a number of Serials that have issues with RAM upgrades. My Serial does not appear to be one of these. However, it does look like R110 is a 680 resistor (and should be a 330) but we'll wait and see if it's an issue.

EXTRA PHOTOS
Extra 1
Extra 1
Extra 2
Extra 2
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a1exh
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Re: Restoring an A3020

Post by a1exh »

Good luck. I'll enjoy reading your progress
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arkiruthis
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Re: Restoring an A3020

Post by arkiruthis »

Tantalizingly close to being able to play one of my favourite games! But as I suspected the LCD TV doesn't support the VGA mode. :lol:

I've put in a GOTEK (on a temporary basis) and upgraded the RAM to 4096 today. The replacement 9-pin DIM is on the way as well.


https://www.youtube.com/watch?v=Fg9mdzZAXd4
steve3000
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Re: Restoring an A3020

Post by steve3000 »

arkiruthis wrote:
Wed Jul 21, 2021 6:49 pm
Tantalizingly close to being able to play one of my favourite games! But as I suspected the LCD TV doesn't support the VGA mode. :lol:
Samsung TVs will support standard VGA no problem…just not pre-VGA low resolution 15kHz/50Hz modes.

To get round this first try *Configure Monitortype 4 (this forces SVGA - which works fine on later Archimedes like the A3020) then use LCDGameModes: viewtopic.php?p=64955#p64955
arkiruthis
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Re: Restoring an A3020

Post by arkiruthis »

steve3000 wrote:
Thu Jul 22, 2021 6:07 am
To get round this first try *Configure Monitortype 4 (this forces SVGA - which works fine on later Archimedes like the A3020) then use LCDGameModes: viewtopic.php?p=64955#p64955
Thanks Steve, that's really helpful!

Sadly, I may have hit a showstopper in this restoration. :(

I've found that the main keyboard isn't functioning correctly. The NUMPAD seems to be fine, but the main QWERTY part is putting in keycodes I don't recognise (or nothing at all, or emulating backspace, etc.).

I've taken out the keyboard, removed the membrane (which seems perfectly clean, though I wiped it down with IPA again), re-assembled, cleaned the ribbons and the ribbon slots, and booted up again. Still the same codes. This means I can't even type in the commands, sadly.

This is the result of typing "QWERTYUIOP" into the text editor.
QWERTYUIOP
QWERTYUIOP
steve3000
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Re: Restoring an A3020

Post by steve3000 »

Looks like one of your Ctrl keys is stuck down. Have you fully disassembled the keyboard (removed keys and the membrane layers) to clean?
arkiruthis
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Re: Restoring an A3020

Post by arkiruthis »

steve3000 wrote:
Thu Jul 22, 2021 9:49 am
Looks like one of your Ctrl keys is stuck down. Have you fully disassembled the keyboard (removed keys and the membrane layers) to clean?
Yes, I've taken it apart a few times now. I did remove the keys and individually clean all of them, replaced the springs and put them back in. I wonder if some of them are now excerting pressure on the membrane pads?

To diagnose the issue, should I consider just testing the membrane in isolation without the actual mechanics on top (if that's possible)?
arkiruthis
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Re: Restoring an A3020

Post by arkiruthis »

Ah okay... prodding the membrane with a rubber stopper actually gets the right keys, this is positive!

I was able (with a little rubber plunger) to manually type out "* configure monitortype 4" and it fixed the display issue (image attached!) so thanks for that gem! :)

So the membrane is fine, therefore the mechanics of the keyboard section is applying some degree of undue pressure onto the membrane. I feel like this was working before I manually removed all the keys, and washed and cleaned them individually.

Looking at the underneath, the spring edges protrude a little bit (equally across the board) but they all protrude equally. I feel like when I clip the mechanism together some of the restraining clips are really hard to push in again, which makes me think that may be the issue?

[EDIT - I think it's the springs! I didn't realise you have to properly push them up into the keycaps so that they 'stick' ]
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arkiruthis
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Re: Restoring an A3020

Post by arkiruthis »

MILESTONE REACHED

One thing I really wanted to see was StarFighter 3000 running on it... and here we are!


https://www.youtube.com/v/IDoPmOYPRp4&hl=en&fs=1

I always found the game technically impressive as you couldn't really get that kind of realtime texture mapping on the Amiga 1200 (maybe Atari Falcon 030?). No matter how janky it must look now, I still feel it's quite amazing for it's time.
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