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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Blatboy on May 25, 2015, 03:34:01 AM
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I was attempting to repair an A3000 I had recently obtained.
It worked when I first got it, then I moved it around some. When I set it up again, I got a blank screen when booting...
I worked on the issue for a couple evenings. After taking it apart a couple times I found the culprit! The crystal had fallen out of it's socket in the A3640. I put it back in.
When I put it back together and flipped the switch, finally I got an image on the screen! Huzzah! Hmmm, the power light on the front of the computer wasn't on...hmmm... what? Is that magic smoke I smell escaping from my A3000? Power down!!!
Alas, the smell was coming from the PSU. And now, it won't power up again. I was so close to getting it back working, and it seems now I fried it. Aaaaaargh!!!
So, I see that I can possibly replace the PSU with an ATX supply (http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=1164), but I'm concerned. What could have caused the original PSU to do that? I'll admit I had really given it a serious go today, constantly powering up and down while troubleshooting.
I'll admit I didn't have the chassis attached when I powered it up (the one that holds the HD and the FD)... it was just sort of resting, more or less where it was supposed to be. Could that have caused a short or something?
I opened up the PSU and took out the fuse... I don't think it's blown... but I'm not 100% sure. Since I smelled bad things coming from there, perhaps I shouldn't bother with even trying a new fuse and I should just get a new PSU.
any input from you very experienced Amigans would be so appreciated!
Thanks!
*sigh*
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I opened up the PSU and took out the fuse... I don't think it's blown... but I'm not 100% sure. Since I smelled bad things coming from there, perhaps I shouldn't bother with even trying a new fuse and I should just get a new PSU.
Thanks!
*sigh*
Oh man... I gotta admit I know nothing about A3K PSU's.... ahhhh, sorry... but when I came to this sentence I thought "Substitute the word PSU with Girlfriend".... :lol:
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Yuk yuk yuk aw man.
ahem.
I do have the know how to replace the caps in the PSU, which look a little bloated. However, perhaps the damage is already done?
Maybe I'll try a new fuse... if that works, then I'll replace the caps...
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If you go that route take the PS out of the Amiga befor you power it up again. If it turns on then go to the next step. No point in damaging anything else.
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Totally understand. However, if it's not hooked to the computer how do I tell it's working? A meter? Will the supply work without a load?
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Everything inside the PS will power up even without it hooked up so that will at least tell you is its ok.
Yes, you can use a meter on the pins to look for voltage.
http://www.hardwarebook.info/Amiga_3000_Power_Supply
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Someone accidentally shorted there power supply earlier this year by letting their hard drive touch the motherboard. They eventually replaced the PSU and everything was working normally.
That might be what happened. A 12V short would have drawn a lot of amps.
It sounds like you should have been more thorough at the start. Most of us learned to find faults by 'process of elimination.' Check each card individually etc.
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Thanks for the link! This shows a diagram of the pinouts:
http://www.oocities.org/ovegun/Amiga-3000/A3000powersuply.html
The HD was on the chassis, but the chassis perhaps was touching something on the motherboard it shouldn't. This is my guess. I should have been more meticulous about that. I was so excited about finding the problem I cut corners. Thank goodness for society I don't do something for a living that puts lives on the line. *sigh*
Anyhoo, I'll be ordering some fuses (250V 5A) and will start from there... on my workbench, not in the computer! If it's not just the fuse (I did smell the smoke after all) I'm hoping switching out the caps will do the trick. Those were on their last legs from the look of it anyway.
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I opened up the PSU and took out the fuse... I don't think it's blown... but I'm not 100% sure. Since I smelled bad things coming from there, perhaps I shouldn't bother with even trying a new fuse and I should just get a new PSU.
When you said this, I wondered if you have a meter to use. Any meter should tell you about that fuse, and, which power rail (+5 VDC, +/-12 VDC, etc) failed. It would also be handy for finding a shorted capacitor. If yours has capacitive ranges, you can confirm the spec of each one.
Are there any burned or obviously damaged components in the PS?
You could use some 30 ohm, 5 Watt resistors to load the PS for testing the outputs.
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Wow. You are so right. I have meters coming out my ears. (ok. I have three. There's no probes sticking out of lobes just yet) I can hear my old instructor giving me hell now. Just measure the fuse. Duh.
Regarding the possible failed power rails... is that just a simple resistance check vs ground?
I believe my meters measure capacitance... is that what you mean?
No obvious damage from what I could see... the caps bulge a little, which is a sign of failure to come if it wasn't a cause now.
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Wow. You are so right. I have meters coming out my ears. (ok. I have three. There's no probes sticking out of lobes just yet) I can hear my old instructor giving me hell now. Just measure the fuse. Duh.
Best to get it out of the circuit and test its resistance alone.
Regarding the possible failed power rails... is that just a simple resistance check vs ground?
I'd use the voltage scales ;) , perhaps, with the loading resistors mentioned above. The meter and the resistors would go from the 0 VDC (common or ground) connection to each of the power rails. You are correct, a switching PS should be loaded somewhat to produce its rated voltages. The resistors are less risky than powering the A3000 for testing (Tony mentions a good precaution.).
I believe my meters measure capacitance... is that what you mean?
Again, you would have to get at least one leg of a suspect capacitor out of the circuit to test it with these ranges of your meter. I hope you're handy with a soldering iron. :)
No obvious damage from what I could see... the caps bulge a little, which is a sign of failure to come if it wasn't a cause now.
Those would be the first to check.
I think its worth your time to save the original PS if possible. A PC supply, while usable, is not an exact replacement.
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Thanks so much for all this info.
I took out the fuse. It's still good, which I think is unfortunate. That could have been an easy fix.
Since the PSU doesn't seem to power on (even with the fuse in - the fan doesn't come on either) I should test the rails with the power applied, if I'm looking for voltage, right? And, I'll use the resistor to emulate a load.
I'm taking the PSU out of the computer and will, from this point on, only be working on it on my bench until everything checks out (which may take a while. This started as such a simple fix. Waaaaaaaaahh!)
I'm pretty handy with a soldering iron, and I've built a PSU (a bench lab supply) from scratch (not a kit), so I've got some chops... but (obviously) I'm no pro. I think I can handle this with a wee bit of direction. :) THANKS!
Re: those capacitors... all that hot snot holding them in place!! How do you safely remove that gunk to get to the capacitors?
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If you have built power supplies you know the chain. Test output from transformer then move to full wave bridge and down the line for each voltage output. you'll find it.
Chris
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Since the PSU doesn't seem to power on (even with the fuse in - the fan doesn't come on either) I should test the rails with the power applied, if I'm looking for voltage, right? And, I'll use the resistor to emulate a load.
Yes, you will have to test for voltage (the DC rails) with the power ON, BE CAREFUL. Nicola Tesla always kept one hand in his pocket while testing to kepp dangerous voltages away from his heart. Many of the components, heat sinks, traces, etc will have dangerous line voltage on them! You may have decided that going inside the PS box is not worth the risk. No harm done.
When testing the supply, I would load all rails simultaneously with resistors. Lets revisit those loading resistors. Using Ohm's Law, a 30 ohm - 5W resistor will load the 12 V rails, both the + and the -, with 0.4 amps. MAKE SURE all rails are rated (read the tag on the PS box) for more current than what the loading resistors will draw! If not, adjust the resistance values UP accordingly. The +5 VDC rail could typically take a 15 Ohm - 5W resistor.
If you are getting outside of your comfort zone, google Ohm's Law. You could also run these tests first on a known-to-be-good PS from a disposable PC and monitor how it behaves.
PS fans are often powered by the +12 VDC rail rather than the 120 VAC line.
I'm taking the PSU out of the computer and will, from this point on, only be working on it on my bench until everything checks out (which may take a while. This started as such a simple fix. Waaaaaaaaahh!)
This has come up many times in the recent past. There are many links to modifying PC supplies to Amiga 3000s use on this site. If your supply is confirmed dead, maybe this route would have more valor.
Re: those capacitors... all that hot snot holding them in place!! How do you safely remove that gunk to get to the capacitors?
Carefully and with the power OFF! :)
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If you have built power supplies you know the chain. Test output from transformer then move to full wave bridge and down the line for each voltage output. you'll find it.
Chris
Yes! I know the chain. It's great to be reminded of the process though. Thanks. Seriously.
Yes, you will have to test for voltage (the DC rails) with the power ON, BE CAREFUL. Nicola Tesla always kept one hand in his pocket while testing to kepp dangerous voltages away from his heart. Many of the components, heat sinks, traces, etc will have dangerous line voltage on them! You may have decided that going inside the PS box is not worth the risk. No harm done.
That is probably the only thing Tesla and I have in common. Haha. I feel more comfortable dealing with a PSU than I would sensitive CMOS components or logic components or something like that at this point... so I'm going to take a good hard look at that PSU before I go ATX. It's always an option though, thank goodness.
When testing the supply, I would load all rails simultaneously with resistors. Lets revisit those loading resistors. Using Ohm's Law, a 30 ohm - 5W resistor will load the 12 V rails, both the + and the -, with 0.4 amps. MAKE SURE all rails are rated (read the tag on the PS box) for more current than what the loading resistors will draw! If not, adjust the resistance values UP accordingly. The +5 VDC rail could typically take a 15 Ohm - 5W resistor.
If you are getting outside of your comfort zone, google Ohm's Law. You could also run these tests first on a known-to-be-good PS from a disposable PC and monitor how it behaves.
PS fans are often powered by the +12 VDC rail rather than the 120 VAC line.
I'm no stranger to Ohms law. That said, the process is everything and this is very helpful.
And re: hot snot... I guess it's just isopropyl one needs to get rid of it. That, I have.
https://www.youtube.com/watch?v=dNNqSXgj6DE#t=96
This is great! Thanks for the help!!!
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@Blatboy
When you said smoke did it smell like caps leaking in air spray form ?
Smell is really hard to miss as it smells awful.If Amiga was still showing
picture when smoke came out then caps are your culprit.
Even if they are just a little rised on top you should replace them first ,
some atx PSU won't turn on with blown cap and you should really check
the bottom cause they get bad there as well as the top.
As for the rest components (from experience of fixing mostly ATX PSUs)
the component that fried is black and looks fried , i used that test mostly :)
No experience with A3000 PSUs though.If you get it running (or convert
to ATX) you can check the voltages by setting multimer to 20 V and check
every line (using PSU chasis as ground).Make sure it's quality ATX PSU as it needs -12 V more than regular PC does.
White translucent stuff is just there to keep components in
place and can be safely peeled away :)
On the side note , close PSU before testing voltages on pins ,
I didn't bother to do that until it blew spark in my gazing eyes.
If it blows up closed it's less of a problem.
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Oooh. Thanks! That gives me hope. Replacing caps I can do. (famous last words) And I'll remember to put the cover on when testing...
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Resistors and Caps ordered.
I'll tell ye how it goes...
:)
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I'm a bit lazy and only skim read this thread, but unfortunately this doesn't sound like a typical capacitor problem, especially if you've seen no visual signs of leaking or deformation.
I've noted many of the common problems I've found with A3000 power supplies over the years here:
http://amiga.serveftp.net/A3000_HardwareGuide/booting-problems.html
Look under the 'A3000 power supply common faults' section.
The standard repair process for any such switchmode supply: Check you have about 320V (150V for US models) across the main reservior capacitor - which is the big one. If not, it's a fuse or bridge rectifier fault. And usually these fail due to something else going wrong further into the supply. If yes, it's often a problem with the high voltage chopper transistors (though these usually fail short circuit which blows the fuse and sometimes damages the bridge rectifier in the process) or the low value series resistors (these always fail open circuit).
If that all checks out OK, you might have a switchmode controller fault which is more complicated to diagnose and repair, but this kind of fault is usually less likely.
Hope that helps, good luck with your repair job. And it certainly doesn't hurt to replace aging capacitors, so keep them on order.
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"I do have the know how to replace the caps in the PSU,
which look a little bloated."
I would say they need changing either way :hammer:
What I was wondering is was Amiga displaying picture (still
working) when smell came out.I don't know what else could
go bad with picture still on except caps.
Although bad cap will make transistor overheat but as far as
I know if it dies in the process no picture.
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Yeah, the screen was fine when I smelled smoke. The fuse is ok. I think it was a short though the chassis to the motherboard that may have caused the fault. (I did a half assed job of reassembling the computer to test.) Hopefully nothing else got fried. Thanks for that extra info about the main reservoir caps!
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did you plug the floppy drive power connector offset to one side?
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The floppy's power was connected... though I believe there was another molex there that wasn't... and, yeah...who knows where that thing was.
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Well, I was finally able to open up my PSU last weekend and test it. Everything more or less seemed ok, believe it or not. Boy those load resistors got hot. I expected that though.
Regardless, since I had already purchased the caps, I replaced the caps on the PSU with some high quality new electrolytics.
I reassembled the PSU and installed it in the A3000. It worked... to an extent. However, I do feel 90% sure the power supply is ok. I'm going to do one more little bit of testing with it to turn that 90% sure to 100% sure before I move further.
I do have some other issues (story of my life) but I'll spare you those until I've confirmed that PSU can't be an issue, and only then will I start another thread of questions.
I wanted to make a special point to thank for all your helpful suggestions (especially you Tenacious for your detailed explanation of using load resistors.) I really appreciate it!! You all are a huge help.
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It's very good to see people tackling the problems of vintage computers without giving up. I think many are interested in how you solve the problems at hand.
Just to mention it, Ive had my A3000 appear completely unresponsive in the past (especially after being opened and disturbed) and it turned out to be dirty oxidized connectors where the MB mates to the Zorro daughter board. Food for thought.
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Interesting you say that. Is that just a matter of cleaning the contacts w/isopropyl?
Here's the update:
I did a double check of all the voltages coming from the PSU and every output seems to check out ok.
However, I only get the screen asking to enter a floppy. (Which is further than I got after I thought I fried it, and before I replaced the caps.)
The power light and the drive lights don't come on. The light on the hard drive comes on, but it's obviously not booting from it. This is still consistent w/what I've read (http://amiga.serveftp.net/A3000_HardwareGuide/booting-problems.html) (thanks Castellen!) as symptoms of a power supply issue. However, the power supply fan does work...
When I originally got the computer, this was also a problem. However, when I hooked up a bunch of SCSI equipment to it (that came w/the computer) the computer magically booted from the HD, and the power/drive leds worked. Now, when I hook up that SCSI equipment, in ANY configuration, it still won't boot up from the HD. Furthermore, one piece of equipment, an Iomega Bernoulli, now, when it's connected and powered up, the A3000 power supply won't even turn on. (something shorted?) Ugh. I worked with SCSI a lot in the early 2000s on Macs. I remember feeling like SCSI was some voodoo technology hahah.
That said, this makes me think that there still may be an issue with the power supply. If the output voltages read ok, and I have new caps, does that rule out a problem with the power transistors or the rectifier? Or could that still be an issue?
What I have done:
- Replaced the caps in the PSU with quality Nichicon caps
- Double checked output voltages on all pins - all good here
- Checked pin 24 on the external SCSI port for a reversed diode - I get 5V when power is on - no continuity to ground when power is off - seems ok
- Checked the jumpers on the HD - it is terminated
- Made sure all ICs are seated well (as well as the 3640)
- Tried powering up with no Zorro cards attached
- Tried powering up with just one card attached (I only have two)
- Tried powering up with no floppy attached
- Tried powering up with every possible combination and order of SCSI devices to see if I could recreate the earlier configuration that booted.
There is no problem with the battery. It seems the previous owner took care of that (replaced it) before it became an issue.
It has a 3.1 ROM. I think it's running WB 3.1 on the HD as well, if I remember correctly. From the looks of it, it's pretty maxed out on RAM. It's a tricked out A3000. I want it to work! :) :)
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@Blatboy (http://www.amiga.org/forums/member.php?u=3176)
Next step I would do is start workbench Install floppy and
try to see if HD is there and recognized and if not try to
initialize it and set up partitions.
Also check if HD survived voltage shocks sigh.
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That's a good idea. I've yet to get the floppy to boot from a disk, but I'm using 20 year old WB disks. I'll make a new on on my 1200 and give that a go. Not 100% sure the floppy drive is good. I don't remember it reading anything correctly in the short window I had the computer working. That said, I had 2 other floppy drives hooked up at the time and I didn't make good notes of what worked and what didn't.
Thanks
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One problem leads to more...
Seems the floppy drive doesn't want to play nice. I created new 3.1 Install and WB disks using my 1200. DF0: on the A3000 keeps saying "Not a DOS disk in device DF0". I took an old floppy drive from an A500 that I know isn't working (gee I wonder where this is going) and it almost worked...at least it got to the WB screen... but then I got errors.
I guess if I'm going to go this route to see if the HD shows up with the 3.1 install disk, I'll need to pilfer a working floppy drive from my 500 or 1200...
My gut still thinks it's a PSU issue, especially since the power and drive lights aren't lighting up on the front panel. When the computer worked magically before, those lights came on. I think perhaps the HD isn't getting enough juice or something. I'll take the PSU apart again and test the rectifier, which I neglected to do before. That said, if the rectifier or the power transistors were failing, I wouldn't be getting correct voltages on the outputs, right?
I don't really have a way to test the drive, as I don't have another machine that takes SCSI drives (ok I have a Mac Classic II but I don't think that will do me any good at all.)
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It is possible to get correct voltages and still fall down under load but not typical. Disconnect the HD and see if it will boot from floppy.
Chris
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if you get the insert workbench disk screen, more than likely the power supply is fine. i would work with the floppy first and see if it will load workbench.
just fyi, if the floppy data cable is backward you will usually get a solid light,if its right listen for the clicking :D
you can also hold both mouse buttons down and get into the early startup menu on power up.
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Yeah, I figured out the way the drive cable goes in. That original df0 is toast. No good.
The computer's not seeing the hard drive. The light on the drive itself is on, but that's it.
I was finally able to load the HDTools utility, (after trying 3 external floppy drives and re-creating the install disk twice) and, unfortunately, no hard drive shows up on the list after the SCSI scan. It also doesn't show up as an option when I go through the boot option screen (2 mouse buttons down)
I double checked all the HD connections, and unless I have the SCSI cable in backwards (which actually looks hard to do, one would really have to twist the ribbon cable around to do that..)
Again, since the power light on the front panel refuses to turn on I'm still leaning towards that PSU. Yet... maybe it's a scsi issue? I noticed the SIL sockets right by the HD connector on the motherboard weren't populated. Looks like some resistor networks would go there... perhaps some sort of SCSI termination?
(http://www.blatomaster.com/pics/IMG_1774small.jpg)
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Probably not a PSU issues anymore and I don't think hard drive is
broken (or at least I hope).Someone who has A3000 could probably
offer some more advice.
P.S. Don't populate anything that wasn't populated unless someone says it's ok :)
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Of course I'm in the middle of a big deadline, so this is how I'm spending my time. Oy. I'll never learn.
Regardless...
Yeah. You're right. The unpopulated sockets are probably a red herring I shouldn't even consider...
More clues:
Clue 1:
(http://www.blatomaster.com/pics/IMG_1777.jpg)
Bootup sequence colors. Regular colors not happening. I get black screen with stripes before I get the enter disk screen (or WB screen if booting from floppy.) According to Castellen's page (http://amiga.serveftp.net/A3000_HardwareGuide/booting-problems.html) that points to a ROM/CIA issue. How to go forward with this? Order new ROMs? Call the CIA? The FBI? Oy bad joke.
Clue 2:
(http://www.blatomaster.com/pics/IMG_1776.jpg)
Battery: Reading up on this, the battery, if not working, could be a source of SCSI woes. I attempted the setclock command, which, when used without arguments gave me no error, which I think would seem to say the battery is ok. For a second opinion, I ran the time prefs program off the 3.1 extras disk. The time was set to sometime in 1994. I changed the date and saved. I powered down the computer, and unplugged the power from the PSU. I rebooted. It seemed to remember the new date. Does that prove the battery is operational? I may consider putting a new one in regardless. Maybe even the same kind since it looks like a solderless solution, and he's had put some slick velcro holding it in place.
Anyway... I hope I'm not babbling too much here and being a nuisance.. You don't hear from me for years, then I come on and bug the living daylights out of you.
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Of course I'm in the middle of a big deadline, so this is how I'm spending my time. Oy. I'll never learn.
Regardless...
Yeah. You're right. The unpopulated sockets are probably a red herring I shouldn't even consider...
More clues:
Clue 1:
(http://www.blatomaster.com/pics/IMG_1777.jpg)
Bootup sequence colors. Regular colors not happening. I get black screen with stripes before I get the enter disk screen (or WB screen if booting from floppy.) According to Castellen's page (http://amiga.serveftp.net/A3000_HardwareGuide/booting-problems.html) that points to a ROM/CIA issue. How to go forward with this? Order new ROMs? Call the CIA? The FBI? Oy bad joke.
Clue 2:
(http://www.blatomaster.com/pics/IMG_1776.jpg)
Battery: Reading up on this, the battery, if not working, could be a source of SCSI woes. I attempted the setclock command, which, when used without arguments gave me no error, which I think would seem to say the battery is ok. For a second opinion, I ran the time prefs program off the 3.1 extras disk. The time was set to sometime in 1994. I changed the date and saved. I powered down the computer, and unplugged the power from the PSU. I rebooted. It seemed to remember the new date. Does that prove the battery is operational? I may consider putting a new one in regardless. Maybe even the same kind since it looks like a solderless solution, and he's had put some slick velcro holding it in place.
Anyway... I hope I'm not babbling too much here and being a nuisance.. You don't hear from me for years, then I come on and bug the living daylights out of you.
edit:
if it is holding time, batt should be ok, just measure the voltage on it.
should of read closer before replying.. looks like you have it booting.. pull any all expansion cards out that are not needed. this will narrow things down.
seems you managed to boot a disk, do have you tried hdtoolbox?
you can swap the cia's with one another and see if symptoms change.
double check the part numbers on the roms, someone may have swapped in incorrect roms, its doubtful but it might happen. i had this problem on a a4000 someone put 1200 roms in, it booted but would never see fast ram :)
i have been an amigan since 87 and owned tons of 3000's and repaired many in the past, not saying i am some kind of expert but..... dont worry about the internal termination sockets for resistor packs, its better they are gone, just make sure you run a terminator on the last internal drive and a external terminator on the db25.
the battery does keep scsi prefs,mostly if its set to async or synchronous etc. It will default back to async when the battery was removed. it will run fine without the battery in almost every case. You can use setbatt.lha off aminet to set these prefs,of course if you can't boot the machine you cant set this.
Check the western digital scsi chip, the latest has a -08 in the part number at the end, or it can be a amd 33c93a.. proto does not matter as long as its either of the ones i mentioned. the 04 and earlier ones have problems with more than 1 hd sometimes but should work with 1 drive . check for term power,you are looking for close to +5v- on the external scsi connector its pin 25,internal 50 pin connector i *think* its pin 26(please verify this first!).. BE CAREFUL! any shorts could kill it and ruin your day. without term power terminators do not work. if no power, check diode d800 i think it is,some are shorted,some open,some installed backward on some boards.
you need to get a working floppy on it, then boot with a install disk and run hd tools to look at the hard drive partitions and or partition/format the drive. if the current HD isnt set to bootable or the filesystem is messed up,it wont do much.
Good luck and keep us posted!
Mech
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thanks Mechy
Just measured the battery. Outputting -15mV. I'd say that thing is toast. I've been able to run HDTools, and it just doesn't see the HD.
I'll see if I can order another battery like the one I have. That'll make for easy installation.
I'll check out the CIA chips. I'm not sure where they are, but it's nothing the internet (the oracle) can't tell me.
Thanks again
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thanks Mechy
Just measured the battery. Outputting -15mV. I'd say that thing is toast. I've been able to run HDTools, and it just doesn't see the HD.
I'll see if I can order another battery like the one I have. That'll make for easy installation.
I'll check out the CIA chips. I'm not sure where they are, but it's nothing the internet (the oracle) can't tell me.
Thanks again
Ah ok,i amazed the clock held time after power off and on with that dead of a battery :D
the cia's are marked 8520(u300,u350)..
be sure to check term power and d800 diode,but it sounds as if the HD may be bad. if you have a scsi card in a peecee it might be good to check with it. otherwise try another hd.
mech
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(http://www.blatomaster.com/pics/IMG_1803.JPG)
So, I was able to get it to boot up from the HD, but there is still some SCSI voodoo going on.
It won't boot up from the HD if there is no external SCSI device attached. If no SCSI device is attached externally, the HD won't spin up at all (power light on tho.) And, even if there is an external SCSI device attached, sometimes the power supply doesn't come on at all, and sometimes it does, and the HD boots up. I can't find a rhyme or reason to it.
I swapped out the CIA chips... no change there. I still get a black screen with vertical stripes when booting (see earlier photo), and I don't seem to get a typical set of boot sequence colors. I have no idea if this is also an issue.
Front panel power lights and HD lights not coming on. I seem to remember they did come on in the past when it booted via the HD. I could be wrong on this though.
A fresh battery was installed and it tests at a nice 3.6v.
I've downloaded setbatt from Aminet, and unpacked it onto a floppy. I've not tried it yet, as I'm not quite sure what I should do with it after reading the docs.
I did enough testing on the HD to feel pretty sure it's ok... and so is the power supply methinks.
So, it kinda works... I had to put the computer away for now though and who knows if it will work when I get it out and wire it up again...
Thanks again for all your help :cool:, and of course if any of this SCSI weirdness sounds familiar to anyone, any suggestions would be welcome.
I had some fun snooping around that HD. There's lots of good stuff on it. Up to now, I've never dealt with any WB past 1.3. So, this is all fairly new to me.
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(http://www.blatomaster.com/pics/IMG_1803.JPG)
So, I was able to get it to boot up from the HD, but there is still some SCSI voodoo going on.
It won't boot up from the HD if there is no external SCSI device attached. If no SCSI device is attached externally, the HD won't spin up at all (power light on tho.) And, even if there is an external SCSI device attached, sometimes the power supply doesn't come on at all, and sometimes it does, and the HD boots up. I can't find a rhyme or reason to it.
I swapped out the CIA chips... no change there. I still get a black screen with vertical stripes when booting (see earlier photo), and I don't seem to get a typical set of boot sequence colors. I have no idea if this is also an issue.
Front panel power lights and HD lights not coming on. I seem to remember they did come on in the past when it booted via the HD. I could be wrong on this though.
A fresh battery was installed and it tests at a nice 3.6v.
I've downloaded setbatt from Aminet, and unpacked it onto a floppy. I've not tried it yet, as I'm not quite sure what I should do with it after reading the docs.
I did enough testing on the HD to feel pretty sure it's ok... and so is the power supply methinks.
So, it kinda works... I had to put the computer away for now though and who knows if it will work when I get it out and wire it up again...
Thanks again for all your help :cool:, and of course if any of this SCSI weirdness sounds familiar to anyone, any suggestions would be welcome.
I had some fun snooping around that HD. There's lots of good stuff on it. Up to now, I've never dealt with any WB past 1.3. So, this is all fairly new to me.
scsiprefs.lha might be easier than setbatt. use it to set up scsi prefrences, setting it to synchronous will gain speed. I wouldnt do that until you have the scsi chain sorted.
Not sure what colors you are looking for at boot time, its just a switch between dark and light grey when things are going well. the stripes are likly caused by the lcd and not there on a proper crt. - it could also explain why you dont get the color you think you should.
What you describe is normal scsi termination problems. Assuming you have +5 term power on the scsi bus properly(check pin 25 of the external port-BE CAREFUL to not short anything and be sure you are on the right pin!).
Without term power, nothing works-not even terminators.
the WD -04 chip is known to also have problems with multiple devices, i dont recall if you said it already has the latest -08 or the amd 33c93a.
The power supply not coming on at all almost sounds like a short, maybe the device you are plugging in is shorting it-get a proper external terminator instead.
there is no scsi weirdness there, just lack of proper termination. since there are no terminating resistors on the motherboard, you need to terminate the external port.,you are in a sense doing this when u connect the external drive. If you need a db25 active terminator let me know,i have tons cheap...$4+ship
Most users run with internal devices,no motherboard terms,and although this works in many cases,its not correct. a external terminator should be used. most 3000's came with these but many have been lost.
Understanding how the basic scsi bus works and terminating it properly will go a long way in preventing frustration. This is the most common thing i see with 3000 owners in the last 20 years-always wrong or missing termination and they all claim "weirdness" :))
the led problem is likely the led board has a cracked trace or bad solder, its nearly impossible to see the broken trace, so continuity check it.
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Hmmm. I have one terminator and it's one of those Centronics jobs... to get that directly on a DB25 takes about 3 adaptors (as I don't have the correct one) and goodness knows if it even does what it's supposed to do with all that extra stuff attached. My SCSI issues have been so whack, it'd be best to get one of yours. I'll send a PM.
That said, when I attached the Centronics one hooked to the CD drive I had attached to the A3000 when it the computer worked, there was no change in behavior. (First time it worked it wasn't attached...I think.) It seemed to have acted the same way whether I attached that sucka or not. That said, I'll do it again to be triple sure.
I did test pin 25 again and it checked out ok. That said, who knows what I've shorted in the past with my poking and prodding. Haha.
the WD -04 chip is known to also have problems with multiple devices, i dont recall if you said it already has the latest -08 or the amd 33c93a.
Oooh. I have no idea. I'll just look for a chip labeled WD33C93? And if I don't have a more recent chip, can I just source one and plop it in? I've found some threads more or less explaining it. Where do I find the chip on the board? (I'm outta town at the moment and will be back to look Wednesday)
Thanks again!
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Good Day,
The Led's have polarity, I've mistakenly plugged in some wrong way around before, they don't work.
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Good Day,
The Led's have polarity, I've mistakenly plugged in some wrong way around before, they don't work.
I never unplugged the board, so in theory that shouldn't be the problem.
That said, I'm not sure if my memory is failing me here. I think I remember those lights coming on at some point since I've had that computer, but I'm not sure. Maybe I'll flip the connector and see what happens.
Thanks!
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Just a note that I picked up a couple active SCSI Terminators from Mechy and sure enough, that cleared up my SCSI issue. So, I more or less have a working A3000! Yay! Thanks to Mechy and everyone for all the help.
Now, I have a whole new slew of issues I'll be dealing with trying to get some of these SCSI devices to work. I'll start a new thread. That's a threat.
Thanks again!
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I mailed you a db25 terminator... i am confused?
Yes, the scsi chip is wd33c93 with numbers after it. just let us know what chip you have when you get back and we can advise you.
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Just a note that I picked up a couple active SCSI Terminators from Mechy and sure enough, that cleared up my SCSI issue. So, I more or less have a working A3000! Yay! Thanks to Mechy and everyone for all the help.
Now, I have a whole new slew of issues I'll be dealing with trying to get some of these SCSI devices to work. I'll start a new thread. That's a threat.
Thanks again!
On the Front Leds: the little led pcb almost always develops cracked traces,its poorly made. check it for continuity,resolder etc. the other thing that causes them to crack is sliding the front cover on and not taking care to have the leds aligned with the respective holes. also, there should be a plastic insulating washer behind the led board,the screw goes through it.
Workbench 3.1 has scsi drivers for cdroms,but they are not active by default. Copy CD0 from storage:dosdrivers to Devs:dosdrivers.
you must then edit the file for the correct scsi device unit number for the cdrom drive.
reboot and it should work to read cd's.
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Just a note that I picked up a couple active SCSI Terminators from Mechy and sure enough, that cleared up my SCSI issue. So, I more or less have a working A3000! Yay!
Another one (almost) bites the dust(bin) :)
Congratulations.