Reviving a broken Archmedes A3000

Hemdale

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I got an A3000 a few days ago and i'll revive this one in the next days (cleaning, fitting with a AA battery holder and other things).

Here are some pics of the actual state (not cleaned or something else ...).

Archi0.jpg

Archi1.jpg Archi2.jpg

Archi3.jpg Archi4.jpg
 
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I refurbished an A3000 last month, they're excellent machines.

There's quite a lot of battery mess there! :(
 
I had one in a similar state but it is now up and running.

I had to replace the RTC, crystal and a few of the ZERO OHM resistors as well as add an AA battery and now all is good.

Good luck! (y)
 
Ahhh, I still think the A3000 is my favourite Arc. Runs pretty well all the 'classic' software available, upgradeable, and being a somewhat earlier machine endlessly hackable ...if that's your thing.

Messy battery, sadly not a surprise but these boards are usually quite robust and fixable. Yes, very likely AA battery fitted to AUX battery pads via the convenient trapdoor most of these machines is the likely way to go... after a darn good clean + neutralising session + replacement of anything that's gone 'pop' or looks like going...
...advice if I may: The battery guk does seem to travel a looong way with these machines. I'd strongly suggest pulling every socketed chip (at least) on the left side of the motherboard and thoroughly cleaning / replacing said sockets. Also check the keyboard connectors / sockets VERY carefully. A3000 can get very flakey / upset if the keyboard connections or socket for the keyboard controller even slightly mucky... and of course the ROM sockets are right next to the battery.

All the best, looking forward to some 'fresh-new' A3000 piccies.
 
Interested in the AA-story, I have an A3000 where I removed the battery and damage (luckily cleaning was enough) but I didn't do much with it after that besides installing 2mb extra memory.
 
@irix:
More info on battery replacement here: http://qubeserver.com/Qube/projects.html
Go to the Replace your battery! link.

Great machine, glad you've got extra memory for yours (needed). Off floppies not having a CMOS battery is a pain (power on + Delete/R every time) but with upgraded machines, HDD highly recommended, non-functioning CMOS makes them nearly unusable.


Power-Up + One of the following keys:

CMOS:
Delete - resets all CMOS except econet ID
Copy - resets all CMOS except econet ID, reverse sync
R - resets all CMOS except econet, country code, number of floppy and hard discs, and expansion card info.

Monitor:
keypad 0 - select TV style display
keypad 1 - select multiscan display
keypad 2 - select hires-mono display
keypad 3 - select VGA display
keypad 4 - select SVGA display
keypad 5 - select LCD display
keypad . - select automatic display detection
keypad + or - for sync 1 or 0
T - configures seperate sync which is needed by most monitors

...unless you have a 15khz capable monitor most games will need either connection via SCART or VIDC Enhancer.
 
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Thanks to you all for your answers ...

I think, i'll start tomorrow. Maybe there's no need to replacing the ROM sockets with new ones, 'cause they don't seem to be in a bad condition (not that bad).

Concerning the 32.768KHz crystal ... this "could" be one candidate for a replacement.
 
IMG_1654.jpg



This was my battery fix after my initial clean, Using the AA battery bay and LK5. Rechargeable AA.

I would definitely change the crystal, you may need a RTC too.

Looking at the state of the resistors you may find issues with the mouse port..

Russ
 
After the first cleaning (with 50%water & 50% vinegar) i've seen all the crappy mess. The condition of this area is absolutely bad. Many scratches (maybe the old battery and the pieces of rust) and the two resistors L8 & L9 simply fell off. The crystal is broken anyway. So i have to figure it out, what resistors they are exactly. Zero-OHM with 0,25??? Never heared of Zero-Ohm (i only know them from 1 to xxx).

It looks like, that i should replace ALL the resistors from L6 to L14 (are maybe the upper row L7-L9 and L11/L12. The diode D2 looks bad too. I think, that this is the right one ... click.

ArchiMess.jpg

I think, these crystals would be good ... click.

Garbage (n) ...
 
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FWIW: I've seen worse be recoverable... they really are tough old machines.

Apologies if I'm teaching grandmother to suck eggs. Might I suggest:
¬A good session with mix of handwash, neutraliser of your choice, IPA, all mixed up and applied with a softish (old) toothbrush... then bung the lot in a dishwasher set to low. (just the above, no dishwasher cleaner) Anything that doesn't survive that needs replacing.
¬Remove any passives that still have a green tinge and replace along with whatever already fell off.
¬Pads that still look dodgy can ususally be cleaned by: GENTLE application of a fibreglass pencil and IPA. Followed by application of good solder, solder paste, and braid.
¬If it all runs, lovely. Replace ICs / sockets in order of guckyness for long term reliability or if still not working. (the CMOS/Clock IC seems very prone to damage)
¬The mouse port can be a real s*d as given it's position can already have cracked pads that the battery goo will have really gone for. Also the port connectors usually need a good deal of cleaning to be reliable. I wouldn't, however, try to replace the whole thing unless you're v good at this... easily endd up with a mess of lifted traces. (there's a set of aux mouse pads just next door if needed)
¬If all the above fails a few surface traces may have gone. Don't give up! The schematic is available and not complicated for that part of the board. Buzzing out brroken traces and patching them is doable. (I once replaced the entire, similar, clock circuit in a battery damaged A5000 with passives, new CMOS IC, and some kynar)

I hope that helps
 
Thanks for your hints ...

Received the parts today (some crystals, zero-ohm resistors & D2 diodes). I'm a bit busy at work, so i hope i'll receive some results at the weekend and maybe ... this little beauty will run again ...
 
It is nearly impossible to get rid of all these battery remains ... i tried a thousand times. I'm a bit disappointed and I'll clean the board with a circuit board cleaner too (the Sonax Electro Cleaner is a good one)..

I replaced ALL the zero ohm resistors (they had all rusty wires and most of them fell off), the crystal and the D2 diode. After this i solder the battery wires with a diode.

Before:

ArchiMess.jpg

After:

Archi2.jpg
 
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Comming on nicely...
I only just noticed the colour of the silk screen. Looks like you have a really early rev A3000 motherboard there. Proper (metal cased) PSU or one of the cardboard ones?

PS
I *think* you had some 3.1 ROMs, but that machine will certainly have come with 2.0 ROMs. Before you try a test run might I suggest checking the technical manual to be sure the ROM jumpers are right.
 
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It's a cardboard one ...

Archi1.jpg

... and this A3000 has the OS 3 roms. The jumpers were in the right postion before i removed them. But thanks for the info. I really appreciate your help.

One more question:

I've seen, that the battery uses 2x plus and 1x minus? So should i wire both plus with the diode or only one of them (if this is important)?
 
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You can use 'proper' recarhargebles but the simplest option is a single 5v AA with a diode on the positive end:

BatteryCompartment.jpgBatteryWiring.jpg

The diode is just to stop the A3000 from trying to charge a supposedly nonrechargable battery. A good AA seems to last many months this way... The terminals for the battery compartment seem to be a standard fitting. I think I scrounged mine from an old TV remote.
 
Yes, i know the AA with a diode method, but i forgot the LK5. I've seen some people who soldered the battery wires on the old battery place ...

Batteryconnector.jpg


... but soldering two pins on LK5 is still the better method.

I've some of these, so i'll use the innards.


1x18650ha.jpg

Btw ... is there a page, where i could find the different A3000 mainboard revisions?
 
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