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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: leofoe on September 02, 2016, 04:46:07 PM

Title: A600 woes
Post by: leofoe on September 02, 2016, 04:46:07 PM
I've got a Vampire!:p
But now I have a problem with my A600! :angry:
Every boot the computer has a delay. The colder the Amiga, the longer the delay. During the delay, the CapsLock led is on.
So, when I switch on the Amiga in the morning, the delay could be 30 or more seconds. If I leave it on the CapsLock led will eventually go off. After some more seconds, the A600 will boot. A reboot also always has a delay of about 8 seconds.
Now, all these symptoms are with or without the Vampire.

FYI: this Amiga is recapped with ceramic capacitors. But it didn't show this behaviour right after the recap. It has been about a year and a half in storage since.

Hope someone has an idea.
Title: Re: A600 woes
Post by: Acill on September 02, 2016, 04:54:08 PM
Quote from: leofoe;813399


FYI: this Amiga is recapped with ceramic capacitors. But it didn't show this behaviour right after the recap. It has been about a year and a half in storage since.

Hope someone has an idea.


The first thing I would do is take off your hard drive and see if the delay is there with just booting a WB floppy. The delay could be an issue with the compact flash or HD controller.

Most important I would get that thing recapped properly. Ceramic caps in place of the proper ones are not in th design for a reason. Using them is not better! Get good high quality long hour under higher temps and they will last the lifetime of you using it.
Title: Re: A600 woes
Post by: Cosmos Amiga on September 02, 2016, 05:05:47 PM
Maybe micro-cracks on the 68000 soldering : http://leblogdecosmos.blogspot.fr/2010/10/micro-cracks.html

Very easy to fix : put some fresh soldering on each pins !
Title: Re: A600 woes
Post by: leofoe on September 02, 2016, 07:49:45 PM
Quote from: leofoe;813399
FYI: this Amiga is recapped with ceramic capacitors. But it didn't show this behaviour right after the recap. It has been about a year and a half in storage since.


As far as I can recall it DID show this behaviour BEFORE the recap. It was the main reason to recap! :idea:
Title: Re: A600 woes
Post by: arttu80 on September 02, 2016, 10:19:09 PM
Hi!

Do you happen to have df0: drive in place? If not, it will cause some delay if I remember correctly. Power supply issue perhaps? Try another one if possible. Anyway, try to eliminate all external (and internal) peripherals to pinpoint this problem into mainboard.
Title: Re: A600 woes
Post by: leofoe on September 03, 2016, 08:17:09 AM
In the meantime I have dug out another A600, that not yet has been recapped. This one works flawlessly with and without the Vampire and the same PSU.
And what's more: at last I could pop the Vampire on the CPU rock solid for the first time. It always was a mess with a non starting A600, having to push the Vampire before it would do anything or giving a green or yellow display. This very problem I also had with the Vampire V1.

Now the question is: what can be wrong with the recapped A600? I will try to resolder the CPU. Anything else I should take care of? In a thread on EAB (http://eab.abime.net/showthread.php?t=73265) I read that this behaviour would be a capacitor problem.
Title: Re: A600 woes
Post by: leofoe on September 05, 2016, 12:32:37 PM
I resoldered the 68000: no change.
Title: Re: A600 woes
Post by: Acill on September 05, 2016, 02:34:16 PM
Quote from: leofoe;813517
I resoldered the 68000: no change.


Did you try to remove the HD cable and boot from floppy as I asked? Any change?
Title: Re: A600 woes
Post by: paul1981 on September 05, 2016, 06:50:13 PM
Have you tried reseating the Kickstart ROM?
Title: Re: A600 woes
Post by: Tenacious on September 05, 2016, 07:13:47 PM
Quote from: leofoe;813436
In the meantime I have dug out another A600, that not yet has been recapped. This one works flawlessly with and without the Vampire and the same PSU.
And what's more: at last I could pop the Vampire on the CPU rock solid for the first time. It always was a mess with a non starting A600, having to push the Vampire before it would do anything or giving a green or yellow display. This very problem I also had with the Vampire V1.

Now the question is: what can be wrong with the recapped A600? I will try to resolder the CPU. Anything else I should take care of? In a thread on EAB (http://eab.abime.net/showthread.php?t=73265) I read that this behaviour would be a capacitor problem.

Shooting from the hip, I would guess one of your new capacitors has failed.  A delay like this is consistent with a leaky cap taking some time to get charged.  Is the delay getting longer?  If so, the cap is probably on it's way to never charging fully and A600 to never booting.
Title: Re: A600 woes
Post by: F0LLETT on September 06, 2016, 09:32:23 AM
Quote from: Tenacious;813537
Shooting from the hip, I would guess one of your new capacitors has failed.  A delay like this is consistent with a leaky cap taking some time to get charged.  Is the delay getting longer?  If so, the cap is probably on it's way to never charging fully and A600 to never booting.


Not sure people realise. You can actually boot your amiga with no electrolytic caps attached (except the main 12v rails). Obviously, running it like that for a long period of time would be silly.
Title: Re: A600 woes
Post by: leofoe on September 06, 2016, 09:46:59 AM
@Accill: Tried that, no change.

@paul1981: Tried that also, no change.

@Tenacious: If I only easily could find out which one!
Title: Re: A600 woes
Post by: paul1981 on September 06, 2016, 01:23:07 PM
Are the board revisions the same? Same Gayle revision? Is the Vampire known to work on all revisions of A600? Just trying to look at it from a different angle.

Wonder if other chips besides 68000 may have microcracks in their soldering?

Have you tried a different floppy drive and cabling? IDE cabling too.