Amiga.org
Amiga computer related discussion => General chat about Amiga topics => Topic started by: blanghorst on February 15, 2017, 03:03:56 PM
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So, I think I've decided to bring my Amigas back to life and play with them, so I'll probably be asking lots of questions. The last time I was here, I had just acquired an Amiga 3000 and a SCSI card reader, which I never quite got working. My Amiga 2000 startup sequence doesn't seem to work quite like I want, so I'll probably eventually post questions about that - I have one of those ROM switchers (DKB?) with a 1.3 ROM and 2.0 ROM and the startup sequence is supposed to detect the currently selected ROM and load the correct WB. For whatever reason, it doesn't seem to work any longer - I suppose that my ROM switcher could be dead.
HOWEVER, the first thing I want to consider is having my systems recapped. Who do you guys recommend for that? Here is some of the work I'd like to have done:
1. Amiga 2000 rev 6.x motherboard - recap
2. Amiga 2000 rev 4.3 motherboard - recap, cleaned, and replace CPU socket. This was my original A2000 board and was damaged by a battery leak. I figure if I could get if fixed, I'll have a backup OR I could slowly start building another A2000.
3. Amiga 3000 board - recap
4. Does anyone recap boards? I have an A2091, a GVP 3001 68030 CPU board, and a Microway FlickerFixer I'd like to get recapped at some point.
5. Power supplies - do you guys get those recapped as well?
Thanks
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So, I think I've decided to bring my Amigas back to life and play with them, so I'll probably be asking lots of questions. The last time I was here, I had just acquired an Amiga 3000 and a SCSI card reader, which I never quite got working. My Amiga 2000 startup sequence doesn't seem to work quite like I want, so I'll probably eventually post questions about that - I have one of those ROM switchers (DKB?) with a 1.3 ROM and 2.0 ROM and the startup sequence is supposed to detect the currently selected ROM and load the correct WB. For whatever reason, it doesn't seem to work any longer - I suppose that my ROM switcher could be dead.
HOWEVER, the first thing I want to consider if having my systems recapped. Who do you guys recommend for that? Here is some of the work I'd like to have done:
1. Amiga 2000 rev 6.x motherboard - recap
2. Amiga 2000 rev 4.3 motherboard - recap, cleaned, and replace CPU socket. This was my original A2000 board and was damaged by a battery leak. I figure if I could get if fixed, I'll have a backup OR I could slowly start building another A2000.
3. Amiga 3000 board - recap
4. Does anyone recap boards? I have an A2091, a GVP 3001 68030 CPU board, and a Microway FlickerFixer I'd like to get recapped at some point.
5. Power supplies - do you guys get those recapped as well?
Thanks
My next job is to attempt recap my A1200 so i will be watching this thread ...
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The 2000s (as the 3000) are notorious for battery leak damage.
I heard good things about Acill, who is on his forum as well.
the 2000 caps leak less likely than the defective SMD caps used in the 4000 and 1200, some also in the 3000.
PSU recap is a great idea, ask Acill if he does that too.
A quick question for the electronic engineers among this crowd:
Some germans seem to love replacing the electrolytic caps with ceramic ones, any problems with that ? Other than microfractures from bending/soldering ? I certainly wouldnt want tantalum caps, they make a mess when they are goners....
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The 2000s (as the 3000) are notorious for battery leak damage.
I heard good things about Acill, who is on his forum as well.
the 2000 caps leak less likely than the defective SMD caps used in the 4000 and 1200, some also in the 3000.
PSU recap is a great idea, ask Acill if he does that too.
A quick question for the electronic engineers among this crowd:
Some germans seem to love replacing the electrolytic caps with ceramic ones, any problems with that ? Other than microfractures from bending/soldering ? I certainly wouldnt want tantalum caps, they make a mess when they are goners....
Yeah, I replaced the batteries on my A3000 and the new A2000 board when I acquired them. My old board was in my Amiga and sitting in my garage for 20+ years and by the time I pulled it out, it was too late.
I am an Electrical Engineer, but I'm too busy and lazy to recap the boards myself especially when the prices I've seen are under $100 per machine.
Thinking about my original post and the issue with the startup sequence and DKB ROM switcher, I bet something is up with the ROM switcher. When I installed the GVP board, the machine wouldn't boot and I found out was the reason was that there was a resistor soldered across one of the sockets that had to be snipped for the accelerator to work. I wonder if that broke the switcher - it really shouldn't have, as I researched and found that solution, but it may have. I seem to remember the startup script working fine back in the day. Maybe I should just pull the accelerator or look for a new ROM switcher.
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ACILL has an affordable recapping service. :)
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Acill all the way! great service and actually knows the systems
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So, I think I've decided to bring my Amigas back to life and play with them, so I'll probably be asking lots of questions. The last time I was here, I had just acquired an Amiga 3000 and a SCSI card reader, which I never quite got working. My Amiga 2000 startup sequence doesn't seem to work quite like I want, so I'll probably eventually post questions about that - I have one of those ROM switchers (DKB?) with a 1.3 ROM and 2.0 ROM and the startup sequence is supposed to detect the currently selected ROM and load the correct WB. For whatever reason, it doesn't seem to work any longer - I suppose that my ROM switcher could be dead.
HOWEVER, the first thing I want to consider is having my systems recapped. Who do you guys recommend for that? Here is some of the work I'd like to have done:
1. Amiga 2000 rev 6.x motherboard - recap
2. Amiga 2000 rev 4.3 motherboard - recap, cleaned, and replace CPU socket. This was my original A2000 board and was damaged by a battery leak. I figure if I could get if fixed, I'll have a backup OR I could slowly start building another A2000.
3. Amiga 3000 board - recap
4. Does anyone recap boards? I have an A2091, a GVP 3001 68030 CPU board, and a Microway FlickerFixer I'd like to get recapped at some point.
5. Power supplies - do you guys get those recapped as well?
Thanks
Amiga 2000s do not really need recapping.
And with through hole caps, its actually a more expensive job than many other Amigas.
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Amiga 2000s do not really need recapping.
And with through hole caps, its actually a more expensive job than many other Amigas.
Why don't A2000s need recapping? They have the older electrolytic caps, right?
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Why don't A2000s need recapping? They have the older electrolytic caps, right?
They should last a heck of a lot longer than the SMD types in the A600/A4000/A1200/CD32 which at the time most were of poor quality. This is the same for other computers though too which used SMD caps which were built around that time. Most Amigas will need to be re-capped now as the risk of motherboard damage from leaking electrolyte is very real and likely happening right now on YOUR Amiga to some extent. Mind you, those models are 25 years old so it is excusable.
:laughing:
Basically, those SMD types were still fairly new tech at the time and apparently there were a few teething problems. :)
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Thanks for the recommendation guys. I can do all that, and they are right about the through hole recaps. Its not typically needed but only way to know is to remove a few random caps to test the capacitance. Cant do it in circuit. Shoot me a message and id be glad to give you a quote. Can even do it all ovee time if you like.
As far as why they dont need it is basicly they were top quality at the time, smd was newer stuff and well sucked at rhe time. All machines vuilt back then with smd need recaps now.
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Some germans seem to love replacing the electrolytic caps with ceramic ones, any problems with that ? Other than microfractures from bending/soldering ? I certainly wouldnt want tantalum caps, they make a mess when they are goners....
i think they replace them with tantalum. ceramic are not polarized, and through hole ones work usually with low capacities. they can't replace polarized electrolytic in all case.
tantalum are really great nowdays. (and when i say nowdays, i think about something around 20 years now :D)
they maybe have been more problematic at their begin, as for first gen smd electrolytic... but nowdays they are "mastered", and are wildly spread.
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Do not use tantalum they explode if installed wro g an ceramic are just wrong. I use better than required hybrid polymers from Panasonic. They will never leak or fail in your lifetime.
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tantalum can explode as electrolytic can too... they are wildly used now, and some amiga extension card use them for more than 20 years now without any problems (CV64 - 64/3D, blizzard, cyberstorm... for exemple)
tantalum is an old technology, late 70's early 80's...
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I use better than required hybrid polymers from Panasonic. They will never leak or fail in your lifetime.
but may fail when your great great grand children get their hands on it :P
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tantalum can explode as electrolytic can too... they are wildly used now, and some amiga extension card use them for more than 20 years now without any problems (CV64 - 64/3D, blizzard, cyberstorm... for exemple)
tantalum is an old technology, late 70's early 80's...
And they were designed with them. I refuse to not use the components the circuit was engineered to use. If you want better you use higher spec parts, not different parts than intended.
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they were designed with, yes. they should have put classic aluminium instead to reduce costs. they did this choice because they wanted durability.
you can replace without any problem aluminium electrolytic by tantalum. the major difference is... price.
tantalum are best than aluminium on every aspect. they could work at higher temperature (125°C) without reducing lifespan. they have less leaking current, more precision in capacity, ect...
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(shrugs) Any type of component or capacitor can fail.
Typically A500s, A2000s fail less, but no component lasts forever.
The thing with capacitors is, they can go bad on you, and you don't even notice.
Other times you certainly do. My Rev1B A1200 is looking quite healthy so far but it's early days yet, the keyboard is half dead at least, but I have the means to bypass that little issue... :)
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Thanks guys! Acill, I'll send you a message in the next couple of days.
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Hi.
So, I think it hasn't been explicitly mentioned.
Do PSU's need recapping? I'm mostly interested in A500/A600/A1200 PSUs.
Manfred
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I have done an FAQ re reapping that may answer some of the questions:-)
https://www.amigapassion.co.uk/recapping-faqs/ (https://www.amigapassion.co.uk/recapping-faqs/)
Steve
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From personal experience, it is a good idea to do the GVP Spectrum 28/24 boards' caps. Particularly the two (typically yellow) parts below the clock part, to the right of the unused ROM socket. I know of two instances where they fried (one was mine). Replacing them with high quality SMD Hybrid Electrolytic is sufficient. They are for digital noise filtering.
GVP's earlier boards used TH electrolytic axial caps for noise filtering, and they don't seem to have any issues. The mini TH ceramics by each TTL IC are no issue, nor are the similar SMD mini ceramics on the later boards near TTL chips. The later SMD boards started to get the larger-value ceramic or tantalum caps parts in a few places, and they should be done. If the board is strictly digital (CPU, memory, SCSI, basic I/O) and has them for basic noise filtering on the power planes near the edge connector or close to a clock chip, go with SMD Hybrid Electrolytic replacements like above.
The parallel-port audio digitizer module, video TBCs, IV-24, and anything that is on the output signals of an A/V product, I would replace them with identical parts.