Amiga 3000 restoration

[ozkano]

recently ı purchased a3000, i try to boot it but not succeed,

need close shot from a working main board for jumper settings

my configuration is

board version is 7
kickstart 3.1
no turbo card
cpu is 16mhz 68030



where should I install eprom 3.1 roms, upper bank or down bank
what will be jumper settings for eproms

[Oldsmobile_Mike]

What does it do when you try to boot?  Have you removed the battery yet??

[ozkano]

nothing gray screen

[danbeaver]

Before you worry about upgrading the KS version, most folks would say to get it operational.  If you want help from other users, giving an idea of what works, what doesn't work, picture of the motherboard (battery area, etc) will help.

[orange]

check the ROM 'bridge', it can get out of socket in transport.

[ozkano]

I removed battery

I cleaned that area with lemon juice and vinegar

I joined one broken trace and checked if there any more

changed dennise and paula sockets

sorry for bad pictures

here are some pictures from battery area

http://retrocu.blogspot.com.tr/2014/10/amiga-3000-restoration.html

[matt3k]

Nice find and good luck with the restoration.

Grey screens can be a few different items.  Make sure everything is seated well and swap the CIA's.  That is the quickest fix for that screen.

Sad that most 3000D's have taken battery damage and need TLC.

[ferrellsl]

I removed battery

I cleaned that area with lemon juice and vinegar

I joined one broken trace and checked if there any more

changed dennise and paula sockets

sorry for bad pictures

here are some pictures from battery area

http://retrocu.blogspot.com.tr/2014/10/amiga-3000-restoration.html

My comment comes a little too late to help you but you should never try to clean up acid-damaged components by adding more acid.  Vinegar and lemon juice are pretty strong acids and can damage components on their own, without the help of the acid that has already drained from the battery.  You should have used baking soda to neutralize the acidity.

[zipper]

Check your facts - the alkaline batterys are alkaline! So mild acid is definitely needed!
Amiga is not an automobile...

[matt3k]

I am always looking for the best advice to neutralize acid.

I can tell you from painful experience that baking soda is a terrible method of removing acid.  I used this trick many years ago and all the 3k systems in that batch failed eventually.

The sandwich layer of traces is tricky to do treat properly.  I try to stay away from systems that took battery damage, because most of the times they come back to haunt you even if they seemed to be treated properly for the damage...

[James2002]

I thought lemon juice is the best way from what I read on amibay.

[danbeaver]

My comment comes a little too late to help you but you should never try to clean up acid-damaged components by adding more acid.  Vinegar and lemon juice are pretty strong acids and can damage components on their own, without the help of the acid that has already drained from the battery.  You should have used baking soda to neutralize the acidity.

As noted, the damaging barrel batteries of that era contained lye or potassium hydroxide (KOH), common car batteries use acid.  As you may remember from your freshman college chemistry course, Many different chemical reactions occur due to differences in the electrical charge potentials between the molecules.  These can be used to generate a charge.

Simply put: White vinegar is simply acetic acid with no left behind Apple goo; lemon juice contains citric acid with the lemon goo.  Baking soda or NaHCO3 (sodium bicarbonate) is a pure base.  One neutralizes a base (lye) with an acid and vise versa.  As to whether on wants to leave behind an organic fruit goo, is a personal choice, but not my personal choice.

Back on topic, I would pull the A3000 schematics off the net and use your multimeter to check continuity of the traces in the affected motherboard area around the battery.  There are several folks in the forums with expertise is diagnostics and repair.

[ozkano]

I checked every traces in battery area nothing seems have problem except one

[mechy]

recently ı purchased a3000, i try to boot it but not succeed,

need close shot from a working main board for jumper settings

my configuration is

board version is 7
kickstart 3.1
no turbo card
cpu is 16mhz 68030



where should I install eprom 3.1 roms, upper bank or down bank
what will be jumper settings for eproms

some things to check. verify +5 and +12 voltages on the psu are good.

Some revision motherboards will not boot without the scsi bus being terminated right.
Some 3000's had term power resistors backward and terminators will not get power. The diode is near the scsi port iirc. should be something over +4v on the external scsi port(pin25 - please verify this pin is right before prodding around!).

Bad chip ram will cause this no boot condition.
remove all fast ram to eliminate a possible problem(the 3000 will boot with only chip ram).
A bent leg on fastram not making contact or intermittent can cause this.
If it has a rom tower, verify its installed right and there are no broken pins.
the 3000 will boot fine with no battery.
the PAL chips sometimes fail.


Anthony has some excellent info on troubleshooting and schematics here:  http://amiga.serveftp.net/
Good luck!

[danbeaver]

The diode Mech mentions is D800 and if working it should be installed with the black line heading IN toward the motherboard.