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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: motorollin on January 12, 2006, 06:12:18 PM

Title: The A1200 that has never "bin" opened...
Post by: motorollin on January 12, 2006, 06:12:18 PM
Well, it has "bin" opened now! :-) (Look here (http://www.amiga.org/forums/showthread.php?t=19527) if you don't know what I'm talking about).

Had a bit of a shock when I opened her up though - just look at this:
(http://i298.photobucket.com/albums/mm244/motorollin/aorg/rust.jpg)

She seems to work ok, and the motherboard looks fine underneath. I wonder whether I should remove that rusty shielding? Would the machine still work ok without it?

--
moto
Title: Re: The A1200 that has never "bin" opened...
Post by: Gav on January 12, 2006, 06:18:05 PM
Hahaha yeah well since it has "bin" opened lol yeah it should be fine to remove the rusty metal but could you not just get the rust off?
I had a A600 a few yr back and the metal was all bent so i just remove the top case of it.
Gav
Title: Re: The A1200 that has never "bin" opened...
Post by: patrik on January 12, 2006, 06:22:40 PM
@motorollin:

Let the shield be there, it will work perfectly for the task of shielding even if it has some rust on it and I doubt you will see the rust when the A1200 is assembled.


/Patrik
Title: Re: The A1200 that has never "bin" opened...
Post by: motorollin on January 12, 2006, 06:24:17 PM
Arrrr I think it's dead :shocked:

Just powered it on, and I think the PSU turned itself off, but I can't quite remember. Now when I turn it on I just get a red screen and a flashing power LED :-(

--
moto
Title: Re: The A1200 that has never "bin" opened...
Post by: Gav on January 12, 2006, 06:28:00 PM
Hmm a red screen usualy means something to do with the roms i think,carefully remove them and replace them and see if that works?
Title: Re: The A1200 that has never "bin" opened...
Post by: motorollin on January 12, 2006, 06:35:35 PM
That's what I thought. I gently pushed down on them but it didn't make any difference. Left it off for a while and it started working. Weird. I've still got my 3.0 ROMs from when I upgraded my main 1200 to 3.1, so if it does it again I'll try swapping them.

--
moto
Title: Re: The A1200 that has never "bin" opened...
Post by: Chain on January 12, 2006, 07:02:25 PM
remove thar rusty {bleep}!

there will be small particles fo rust on board.

remove it and carefuly clean whole board
Title: Re: The A1200 that has never "bin" opened...
Post by: uncharted on January 12, 2006, 07:13:25 PM
That is one skanky A1200.
Title: Re: The A1200 that has never "bin" opened...
Post by: JaXanim on January 12, 2006, 08:20:49 PM
Looks like the machine has been in 100% humidity for quite a while. Rust needs water and water isn't good for electronics.
I'm betting it's a gonner.

JaX
Title: Re: The A1200 that has never "bin" opened...
Post by: motorollin on January 12, 2006, 08:44:45 PM
It seems ok now. I did remove the shielding just in case. I think I have some more from when I towered my main A1200, so I may replace it with that.

In order to remove it I had to take the floppy drive out, and I found something very interesting. Underneath the drive on the shielding was loads of black insulating tape. I turned the drive over and there was an exposed PCB - not something I have had on any of my other Amigas, and obviously the reason for the insulating tape.

I had noticed that the drive was acting strangely. Firstly, it doesn't click when empty. Secondly, if I boot using a Workbench disk then remove the disk, the drive starts clicking like mad, the floppy light comes on and a DF0:NDOS icon appears on the Workbench. If I put another disk in, it reads it and this weird activity stops.

Could it be that the drive has been changed to a non-Amiga one? This would clearly mean that it has "bin" opened after all!

After removing the shielding, I inspected the motherboard. First thing I noticed was that the rust has extended to the shielding on the RF modulator. I then saw a sticker on the motherboard for "Macklin Repair" stating "RF not working". No sh!t.

I'm now convinced that the machine has been opened. The warranty sticker was still there, but was a little bit damaged on one edge. I reckon he took it off then replaced it :pissed:

--
moto
Title: Re: The A1200 that has never "bin" opened...
Post by: Gav on January 13, 2006, 12:33:21 AM
Hi
So does  the amiga work though?I`ve seen a lot of 1200 drives but im not sure if ive seen one with a bare pcb??I do have a couple of drives upstairs that i will inspect later...But yeah its possible it has been opend and just carefully replaced the sticker..But just aslong as it works?Does the RF still not work then?i bought another motherboard as ive had loads of faulty ones but my rf never worked either but was sold like that and i dont use the rf anyways.
Well let us know how you get on with the old girl...
Title: Re: The A1200 that has never "bin" opened...
Post by: AmigaEd on January 13, 2006, 12:41:50 AM
Quote
I then saw a sticker on the motherboard for "Macklin Repair" stating "RF not working".


Well, you didn't expect to find "Repaired by Doomy" did you?


-AmigaEd :-D
Title: Re: The A1200 that has never "bin" opened...
Post by: motorollin on January 13, 2006, 07:03:18 AM
@Gav
Yeah it's working now. I'm not using the RF so I don't know if it works or not. Have you ever seen an A1200 floppy that doesn't click?

--
moto
Title: Re: The A1200 that has never "bin" opened...
Post by: Oliver on January 13, 2006, 07:08:18 AM
Quote

motorollin wrote:
Have you ever seen an A1200 floppy that doesn't click?


no, but I haven't seen all that many 1200's.  They all clicked though.
Title: Re: The A1200 that has never "bin" opened...
Post by: BadBigBen on January 13, 2006, 07:15:41 AM
1.) Mine does not CLICK, though I have a Programm running to not do that... he he he...

2.) I took a look at the PIC, and I never seen a A1200 that only the keys turned YELLOW and the CASE pearly white... LOL...

3.) BTW what does the DRIVE say as to type and who made it...?
Title: Re: The A1200 that has never "bin" opened...
Post by: Doppie1200 on January 13, 2006, 07:17:06 AM
If the rust is not too thick you can remove it using chrome polish. The bumpers of my beetle look like this from time to time and after a good rub with chrome polish they look like new. Only the badly rusted parts leave black spots. But if you feel better with a shiny sheeld go get some chrome polish from your local car shop.

Title: Re: The A1200 that has never "bin" opened...
Post by: Mad-Matt on January 13, 2006, 08:22:25 AM
I have had floppy drived from Mitsumi which has all its installs showing on the underside.  Chinon probably made the most armoured drives and lots of jumpers on back to play with too.  Panasonic drives used in later a1200 are practicaly silent so it may be clicking, just not audiable.  Would have thaught floppy led would have a very slight flicker to it.  If it is a mitsumi drive its internals could be grounding on the shielding which would stop drive functioning properly.
Title: Re: The A1200 that has never "bin" opened...
Post by: Gav on January 15, 2006, 12:46:07 AM
Well ive had a few amigas and i think they all clicked from the drive but yeah there is a program to stop that..
Maybe there is a few out there that dont click then???Who knows but glad its working now..
Title: Re: The A1200 that has never "bin" opened...
Post by: Tomas on January 15, 2006, 12:57:13 AM
Quote
I had noticed that the drive was acting strangely. Firstly, it doesn't click when empty. Secondly, if I boot using a Workbench disk then remove the disk, the drive starts clicking like mad, the floppy light comes on and a DF0:NDOS icon appears on the Workbench. If I put another disk in, it reads it and this weird activity stops.

Seems like it thinks that the disk/floppy is still inserted even when the drive is empty. There is a button or what you call it that is pressed down when a floppy is inserted.
See if this button is stuck or something.

Or as you said, the drive might infact be a pc/mac floppy without this function.
Title: Re: The A1200 that has never "bin" opened...
Post by: Hyperspeed on January 29, 2006, 08:30:25 PM
How did that shielding rust like that, I thought they were aluminium? If it's tin then it must have been left in the garden shed over winter!

:-)

If there's oxidation taking place then everything that isn't surface mounted is going to have transmission trouble - the same happened with the internal power connector in the Sega Dreamcast.

The solution to the Dreamcast problem was to moisten a lint-free cloth with WD40 and rub gently over the connectors. WD40 is excellent for removing specs of rust from chrome (try it Doppie!) and can also lubricate and improve contact.

So maybe try cleaning the ROM legs, floppy header etc. with fibreglass pencils from Maplins and give it a little WD40, same for the shielding (although best clean that after removing it far from the motherboard).

Every Amiga is precious and that motherboard could serve you like a work-horse for many years!

Rusty Amiga I salute you!