Who should I send my 4000 motherboards for repair?

[ceaser]

I have some motherboards to fix and I don't think I can do the work. One needs the sound capacitor job done to it and is a rev. B, the other has the key lock chip on the motherboard broken and is a rev. B also.

The one that probably has messed up sound caps gives a terrible loud ring that overwhelms through any output. You can't leave it on for more than 30 seconds it sounds like an alarm clock. It picks up the electrical interference from the fan and you hear that instead of the audio then. This thing is working beautifully about 48 hours ago. And it was only turned on for about 3 hours.

The other one has key lock stuck on. It doesn't matter whether you take the key jumper from the front bezel off or not. It also has an IDE pin broken, the grounding pin I believe in the lower right hand corner, so the IDE port should be replaced and I have no clue which chip to replace for this key lock problem. There is no difference with or without the key jumper connected from the front bezel. I tested that. It lets you use the keyboard and only click with the mouse. I've read all that I can and that this is how it works when the key lock chip on the motherboard (or traces to it) is broken.

I think both of these need full service. I've been doing a lot of reading and it sounds like pretty much every single capacitor on the motherboard needs to be replaced. I really don't know. I need a link to a good repair service. So far I'm hearing either New Zealand or France are my choices and I live in Minnesota in the USA. I'm pretty decent with the soldering iron but I guess I'm pretty fed up with these obsolete broke motherboards and I just want them to get done correctly by an expert. I want them in a condition that they'll actually last for a while. I want all the common problems taken care of if there's anything that goes out but hasn't gone out yet.

Where should I send my 2 precious motherboards? A.H. in New Zealand or JJ. in France or somewhere else?

I looked at this: http://amiga.serveftp.net/audio_repair.html and I see myself trying to hack my way to a fix. And I don't want to do that. I can figure out some jimmy rig to get the buzz out but I want this thing revived.

Let me know however if you want to dedicate some of your expertise to my plight. I know how to solder. I don't know what to buy for capacitors at all and I have no real knowledge of how to fix Amiga. I see some schematics collections on here but I don't think that's going to cut it in my case. I just don't know enough.

Let me know where to go from here.

Regards
Greg

Here's the stuff the guy said about it in the original listing. The motherboard with the broken keylock chip was the one from this auction. The one with the broken audio was a different one:

Commodore Amiga 4000

Highflyer Expansion System



This auction is for nice clean and working Commodore Amiga 4000 in Highflyer Desktop Case, Highflyer Xtender Card, Additional Dataflyer PSU, Keyboard and Mouse "Pregnant version". This unit had been serviced last year by former Commodore Technician, the memory SIMM sockets replaced with better ones (metal clips), both mouse/game DB9 ports replaced as the originals were loose, Motorola 74HCT174 replaced as the unit had faulty RTC and the Battery had been also replaced with better one (Ni-MH). There is no damage to the board or signs of battery leak as the old battery had been removed couple years ago to prevent leak.

Amiga 4000 Specifications:

* Standard Chip Configuration
* Processor Card v3.1 CPU/FPU 68040
* 2MB Chip RAM
* 16MB Fast RAM
* 540MB IDE Hard Drive
* Floppy Drive, Amtrade The Real HD-Drive A357 (rare)
* Motherboard revision B
* Kickstart ROM 3.0

Highflyer Expansion System:

Xtender Card:

* 1 X Extended Video Slot
* 2 X ISA Slots
* Connects between A4000 Motherboard and the A4000 daughterboard

Additions to A4000

* 2 X 3.5" Internal Drive Bays
* Fan for Cooling
* 250W Power Supply
* 3 X Cutouts for 50pin Centronics SCSI Connectors
* 2 X Cutouts for DB9 Connectors

[davideo]

Originally Posted by ceaser

Where should I send my 2 precious motherboards? A.H. in New Zealand or JJ. in France or somewhere else?

I looked at this: http://amiga.serveftp.net/audio_repair.html and I see myself trying to hack my way to a fix. And I don't want to do that. I can figure out some jimmy rig to get the buzz out but I want this thing revived.

I did the audio repair on my 4000D by following the above website.

I'm now about to start my second 4000D and will be doing the same again.

I've heard nothing but good from other forum users about jj and ah. But looking at anthonys website I personally would send it to anthony if I needed repairs done that I couldn't carry out

Dave G

[Slayer]

Yip, he's one serious and honest Kiwi our Anthony

Only up the road for me...

[Merlin]

Whatever you do, do NOT send it to a guy called Doommaster, from Oregon; you will never see it in the same state again.

[davideo]

Originally Posted by ceaser

Where should I send my 2 precious motherboards? A.H. in New Zealand or JJ. in France or somewhere else?

I looked at this: http://amiga.serveftp.net/audio_repair.html and I see myself trying to hack my way to a fix. And I don't want to do that. I can figure out some jimmy rig to get the buzz out but I want this thing revived.

I did the audio repair on my 4000D by following the above website.

I'm now about to start my second 4000D and will be doing the same again.

I've heard nothing but good from other forum users about jj and ah. But looking at anthonys website I personally would send it to anthony if I needed repairs done that I couldn't carry out

Dave G

[Zetr0]

@Davideo

some great stuff there... double posting inbetween posts.... awesome!

[chiark]

Indeed, fantastic work Davideo

I'd send mine to Antony Hoffman (owner of the amiga serveftp website you reference) without any hesitation whatsoever.

[ceaser]

Originally Posted by Zetr0

@Davideo

some great stuff there... double posting inbetween posts.... awesome!

I read your saga before starting my own thread but didn't want to hijack him or u*

[ceaser]

Originally Posted by davideo

I did the audio repair on my 4000D by following the above website.

I'm now about to start my second 4000D and will be doing the same again.

I've heard nothing but good from other forum users about jj and ah. But looking at anthonys website I personally would send it to anthony if I needed repairs done that I couldn't carry out

Dave G

I read this whole post of yours along with the A4000 problem post directly beneath my thread.

Shortly after the heading "Leaking SMD Capacitors" (Anthony Hoffman's site I guess this is),(if you are actually looking at the motherboard that picture is front-to-back I guess if you were looking at the 4000 from the front bezel side); Just above where C403 is written in the picture of the two flat ones and the 4.7 uF cap, do I want to repair the leads on the just the 4.7 uF and the top brown one? I'm assuming I'd better buy some new ones before I desolder the old broken ones. There's a place called Digi-Key that has parts where I live in MN, USA but they aren't good for advice, only good if you know exactly what to ask for. So I think I just would need to ask for a 4.7 uF electrolytic capacitor to get a suitable replacement for that, but those little brown ones I don't know what to ask for. I know on the other motherboard I have with the burnt key lock chip someone recommended which chip to get and I didn't take the old one out. The chip that came was the wrong chip even though it had a similar number. So I replace the 22 uF capacitors? I see CN433 and CN444. One capacitor marked with 22 over 16v with a bit of blue on the left side of the writing (blue marking) is directly below where CN444 is printed, another just like it below the CN433 writing. Are these possibly also involved in this problem? Or did you do it with an oscilloscope and find out exactly which one it was?

The problem is exactly boots up right away to Workbench 3.1 (w/dir opus 5.5) then after a good 30 seconds the whirring along with the fan motor starts and gets worse until the high pitched noise is totally overloading the speakers. It doesn't matter if you are running a program/game with audio or not, and it's both audio connectors. It doesn't matter if you plug one or both in the ringing will start no matter what.

Good luck trying to figure out my description. It would as always be best if I can pull this job off like I usually do when I have to fix something I like enough to bother with. Thanks so far! Heh sorry I didn't mention I was going to probably try to fix it myself first but I'm almost sure at least one of these 2 motherboards is going to have to go to a real Amiga pro and not a lucky tech like myself.

[davideo]

Originally Posted by Zetr0

@Davideo

some great stuff there... double posting inbetween posts.... awesome!

@Zeets + @ chiark

That's what you get for posting while at poxy work. My PC hung and didn't show that the first message had gone

Dave G

[ceaser]

so I pull a speaker wire off a home theater speaker. I was too lazy to grab the wire strippers so I just twisted real hard. Loosen a screw on the back of the case and hook it in there and screw it back down, noticing that me leaning a bit on the case is grounding it, stopping the hum (horrible screech) almost completely. I screw the other end into the screw in my big power center under the computer desk. It's still humming. I grab another single (like when you tear the 2 parts of speaker wire apart) speaker wire to attach to the other side of the case. It starts buzzing like crazy again so I remove the wire but keep that screw kind of loose. It's still going like crazy so I take the other wire off and leave the screw loose. When I let go, the buzzing is gone.

I know this isn't a permanent fix at all, but at least now I can look for that sound card, and send the 4000 motherboard that isn't being used off for repair when I actually have money! And I can look for a sound card for this one in the meantime.

So I won the battle for now. Who knows it might start again. This thing has 3 fans in it so there's a lot of potential for interference. Ok Regards. Thanks for the recommendations still on repair people because I will be sending the 4000 motherboard that isn't in use in soon, and I'll send this one in when that one is done, of course, it's all about the money!

Peace guys. This was the first time I used this site. Looking good. Glad there isn't *drama* going down.

i've left it on for about 30 minutes now so at least i know if i don't breathe too deeply it won't start again!

[mfletcher]

Id recommend AmigaCenter France for your Mobo repairs. JJB changed the caps on my A4000D, fixed my A4060 accelerate and updated my Blizzard 040 to an 060. All working perfectly. Some folks say he might be a wee bit expensive, but you get what you pay for and so far Ive had no complaints.

AmigaCenter France, 2 thumbs up!

[AMIGAZ]

Originally Posted by mfletcher

Id recommend AmigaCenter France for your Mobo repairs. JJB changed the caps on my A4000D, fixed my A4060 accelerate and updated my Blizzard 040 to an 060. All working perfectly. Some folks say he might be a wee bit expensive, but you get what you pay for and so far Ive had no complaints.

AmigaCenter France, 2 thumbs up!

How much did he charge you for this?

All of a sudden my A4000D has lower sound on the left channel...this A4000 hasn't been turned on for 3 years so I had a feeling something would be rotten :P