A1200 Repair after Failed Recapping Attempt

[@Snowcrash777]

I love your videos. I have a suggestion that will help you avoid pad damage when you are recapping. Use flux on your desoldering wick. It helps mitigate the heat and works as a lubricant plus you can apply a bit more solder to the iron which helps the heat flow through the copper wick and sucks the old solder off the board. After that I put more fresh solder on the iron and a bit more flux and reflow solder across the pad then wipe it with the wick until I have a fresh pad with just enough solder to cover the metal. Give it a try sometime. Best Regards

[@JanBeta]

Thanks! I'm definitely going to give the flux+solder wick trick a shot next time! :)

[@catriona_drummond]

Really need to finally recap my 1200. I will send you the board afterwards as well.

[@KorAllRBare]

*TIP #1 & 2* When using solder wick, first add some Flux to the Wick and watch how fast and clean your work ends up, also even though you are using a desoldering gun and even though they are a pain to maintain, a little flux on the joints before desoldering them will help to avoid damaging traces.. Aluminium Foil doubled up or three Layered is cheaper than Kapton Tape so if you have a large area to protect keep the Aluminium in mind..

[@JanBeta]

I'm going to give the flux+solderwick a shot next time, thanks for the tips! :)

[@RobA500]

Oh dear that’s a poor battle scared A1200, great work getting her going again.

[@sparrowbe4k802]

The Amiga was a real "game changer". Back in the day I was programming "Pyramid Systems" Unix along with the 1991 version of ansi standard ("Microfocus"? or was that cobol??) "C". [I honestly cannot remember the K&R diffs]. Then onto HP-UX then on Sun Solaris machines. Anyone worth his salt in 1999 had a PC *_and_* a "Sparcstation" on his desk. For all of that - it still staggers me that you could buy a Commodore Amiga A500 and program "C" on it. Even now it just doesn't seem real. Oh those linkage errors - nope don't miss *_those_* .

[@LossMiImKraut]

Microfocus was quite a modern cobol development environment back in the day, in as far as on can utter the words "COBOL" and "modern" in one sentence without shuddering and ducking in shame. ;) I used to work with it - quite the magnificient Hacks back then, if I may say so. :)

[@sparrowbe4k802]

​@@LossMiImKraut I remember the dark blue A5 ring bound stylized Microfocus manuals. Anyone who needed a manual shouldn't have been anywhere near a vt100 terminal. I could never understand why any implementations of cobol should be different to one-another. I still don't understand why we needed "77" levels - unless shoving it into a compile time issue somehow improved performance (?????). (Or was it an "88" level?????) Was "77" immutable and "88" the test?? Cannot remember - - - I'm so sorry - I'm not looking it up myself.

[@DavePoo2]

Nice work! When I first saw it, I was going to immediately suggest not replacing all those RF caps, but then you already saw my video and where past me had already done it, so present me doesn't need to.

[@JanBeta]

Your video was super helpful! Literally the first thing that popped up in my search when I tried to figure out which caps are not needed. Thanks, past Dave! :D

[@homelate1306]

Only rev 1B had a capacitor on C460, in other revisions it was absent. I professionally fix and recap Amiga's and I've seen a lot of failed recapping attempts by their owners. If you don't have the proper tools, don't do it but have it recapped by a professional.

[@JanBeta]

Oh, that is good to know, thanks!

[@RETROCENGO]

Great video Jan. I bought couple of recapped Amiga 600/1200 before, I’ll never ever do that again, to many grill-bills out there

[@JanBeta]

Yeah, there are lots of not-so-great recapped Amigas out there, I guess. :/

[@LossMiImKraut]

@@JanBetayea, and now one slightly botched recapped Mac 7100/80 Board - It works now, so I don't give a damn about crooked caps. ^^

[@horusfalcon]

What a repair! The only thing I would have done differently would be to insulate those bodge wires with some "spaghetti tubing", heat shrink, or even some nail polish, just to keep them from shorting. As it is, none of these should contact your RF shields, so you're probably good to go.

[@JanBeta]

Thanks! The magnet wire I used is actually pretty well insulated, so I don't think it's necessary to add additional insulation. The lacquer insulation just melts at the spots you heat up (and it takes quite a while to melt it), so the rest of the wire is safe to run over other components etc.

[@pkf4124]

I have almost identical damage on my 1200 the pads were just gone even with removal with hot air and preheated board etc. I just packed the board away and used another of my Amigas instead. Good to see that many of them are not needed as I removed the RF anyway. So will get it back out and fix it.

[@thebyteattic]

Top job! Repairing the pads with PCB epoxy is messy at best, and often not strong. Electrically, what you did is best.

[@JanBeta]

Thank you sir! I think there would have been more beautiful methods, but they would also involve much more work (and probably wouldn't be as sturdy). I added some strategic drops of hot glue to the through-hole parts in the meantime to stabilize things and it looks like the Amiga is going to survive for some time (hopefully). :D

[@teevok]

Well done, Jan! Excellent video :)

[@JanBeta]

Thank you! :)

[@giuseppelavecchia775]

Sempre grande Jan!

[@raythomas4812]

I miss My A1200, I miss my A500 - I Miss commodore. There was nothing wrong with my machines - I was just in a bad place and just thew everything in a skip ( Atari 400 and CBM 64 too ) not to mention a Technics Turtable and hundreds of cassettes..oh well - I have a Mac Studio now . Great Video Jan

[@JanBeta]

Sorry to hear that! I guess many Commodores saw the same fate. My original Amiga 2000 went to the trash in the early 2000s, too. I regret that decision a lot now but at the time it seemed really obsolete and I didn't have any space to store it. :/

[@nicoful86]

Good job, very satisfying!

[@PaulinesPastimes]

A great result that must have taken a lot of concentration, and steady hands! Considering what you had to work with you have done an excellent job, and it works, which is the main thing. 🏆

[@JanBeta]

Thanks so much! I played with it for a couple of days now and the repairs seem to hold up so far. Also added some hot glue in strategic spots to stabilize the through-hole caps a bit. Hope it's going to last. :)

[@PaulinesPastimes]

@@JanBetaThat's good news. Always enjoy your videos.

[@jamesrizzo295]

Well done and loved your reaction when it booted 1st time! 🎉

[@JanBeta]

I was genuinely surprised (and super happy) it worked on the first try!

[@MrClump]

Nice work. One way I like to work around missing pads is to solder a wire to the foot of the capacitor first; you can then drop it down a via or easily solder to whichever point you need. I then secure the side of the cap that is not soldered down on the board with a tiny bit of hot glue melted into place with the hot air gun. Ends up with a mostly invisible repair.

[@JanBeta]

Thanks! Sounds like a reasonable way to approach the SMD caps. I'm going to try to keep that in mind and give it a shot next time. :)

[@SergZak2023]

Great work, Jan!

[@JanBeta]

Thanks!

[@mk500]

This is a seriously impressive repair! Looking forward to the build. Way to rescue this 1200!!

[@JanBeta]

Thanks so much! I was genuinely surprised that it worked on the first try. I thought it would take lots of reworking until it booted again. :)

[@8bitmanshed]

nice work dude. good to see it back running and in good shape.

[@JanBeta]

Thanks Ollie! :)

[@MikesArcadeMonitorRepair]

Yikes! Great job fixing that mess.

[@draganklep1382]

Great job, i always love to see a working A1200 again.

[@JanBeta]

Thanks! I'm really glad that I managed to bring it back to life. Didn't anticipate it would work right after the first round of reworking. :D

[@draganklep1382]

@@JanBeta i still run my A1200 on weekly basis. Own her for more than 10 years. Done some upgrades like blizzard 1260 + scsi ;) Best Regards from Slovenia

[@crumplezone1]

Fantastic job Jan, another A1200 lives to fight another day !

[@JanBeta]

Thanks! I just hope the repairs are going to last (so far, so good). :D

[@parrottm76262]

Back from the grave! This also makes me so happy. Amiga Forever! :)

[@JanBeta]

I can't tell you how happy it made me when this poor thing powered right up. :D

[@KorAllRBare]

*TIP #3* Toothbrush cleaning can be finalised by placing a paper towel onto the IPA and then brushed away using a toothbrush. It's amazing how good this works..

[@Boris_Amiga1200]

Great fix Jan! Congratulations! 💪

[@JanBeta]

Thanks! :)

[@tenminutetokyo2643]

You can also get new micro inductors to replace the large old ones. They’re tiny - just a few mm.

[@MeinElektronikHobby]

sehr gut und kompetent repariert. man kann immer wieder etwas von Dir lernen.

[@JanBeta]

Vielen Dank! Ganz schön viele Workarounds, aber leider war ja auch recht viel zerstört auf der Platine. Ich bin sehr zufrieden, dass ich das hinbekommen habe. :)

[@KolliRail]

Awesome! Great work, Jan!

[@JanBeta]

Thank you sir! :)

[@ivarjore6741]

Why you not use the twist method, and then clean the pads

[@JanBeta]

The twist mehod can be super risky, especially if the board around the components is already corroded by the electrolyte. At least in my experience. Hot air takes a bit longer but usually is the least destructive method.

[@ralfr.5974]

Awesome! 👍🏻👌🏻

[@JanBeta]

Thanks!

[@jonathanlin9772]

The board is also missing all the clockport pins that are present on most amiga 1200 motherboards.

[@JanBeta]

Yeah, as far as I know they didn't populate the pins on the clock port for most earlier revisions. Typical Commodore. :D

[@8antipode9]

Congrats on a challenging repair! Because of you, I acquired an A500 and an A1000. I put PiStorms in both of them and I've noticed that Arkanoid, Bubble Bobble, and Turrican all do not work correctly with the PiStorm (stock CPU they all work). Wondering if your experience is the same.

[@JanBeta]

I haven't tried those specific games on the PiStorm yet, but my guess is that since the PiStorm simulates a 68030 processor instead of the regular 68000, that the games are not compatible with the instruction set of the higher tier CPU. You might want to try the WHDLoad versions of the games. Sometimes there are compatibility fixes included in the loaders for faster processors.

[@KrautRockt]

hey jan, ich hab mit gefiebert in diesem reperatur video ...und gefeiert bei dem einschaltsignal der WB! respekt dude!....🙂 ich hab mich auch schon gefragt ob man nicht einfach "normale" kondis einsetzen könnte?!?...lg, danke für die tolle "sendung" und eine schönen frühling dir und deinen lieben und allen retro bastlern hier draussen..! le`RoboTronic64/KrautRockt!

[@JanBeta]

Danke!

[@ctchich4469]

Sometimes the retro gods smile on us and the monster lives

[@JanBeta]

Indeed! 😅

[@mattsqwrl]

Well I feel a little better about the recap job I did on my A1200 now! It's pretty tricky, I sure have a good idea of where my soldering limits lay now.

[@JanBeta]

It is not an easy task at all, especially if there already is corrosion around the pads!

[@mattsqwrl]

@@JanBeta No I was lucky, mine was perfect still. I had sound issues but they were actually down to the power supply! Oh well, at least the job is done, I'll make a video about the saga eventually.

[@TPau65]

Wow, a true "Chris Edwards Restoration" style repair and successfully right at the first try! 😁 I always wondered how these coated bodge wire works. The coating melts when heated with the solder iron, did I get this right?

[@JanBeta]

Thanks! Yeah, the magnet wire is pretty handy for these kinds of repairs. It is enamel coated, so the insulation melts at the ends you apply heat to and you can basically just sink it into the solder, heat up (for a bit longer than you usually would) and it's going to make a good connection at that spot. Same stuff is used in transformers, for example (which is also a good source for this kind of wire if you don't want to buy it).

[@rkessing01]

One note, replacing the surface-mount tantalum electrolytics with standard through-hole electrolytics might not be electrically equivalent. I'm assuming the originals were tantalum given the stinky fishy smell as that is a dead giveaway. Anyway, the ESR of the tantalum caps may be lower than the through hole ones that you used. Sometimes ESR is important, sometimes it isn't. It really depends on the specific type of circuit/application. If those two locations are just bulk power reservoirs then I'm sure it will be fine. It is more critical in discrete switched mode power supplies, high power amplifiers and so forth, and not what are likely strictly digital circuits in this case. I've done trace and pad repairs and it isn't easy. I would suggest on that last through hole with no bottom pads, it is perfectly acceptable to float the cap above the board a bit and solder on the top side. That way you get a good bond with the traces that are supposed to originally connect to the cap. I know soldering on the top of the board seems odd, but it does work just fine. You do what you have to and you did a great job on this one! Keep up the great work.

[@RacerX-]

They were not tantalum on that board from factory, they were just SMD electrolytics. The Amiga is not picky here and some places it will even work without the cap all together. Of course it will have more noise but what he did here was completely fine for the A1200. Stinky fish smell is from the liquid electrolyte, tantalum caps are usually solid...

[@JanBeta]

Thanks for the comment and the tips! The original caps are surface mount electrolytic caps so the through-hole parts I used should be completely compatible. The leaked electrolyte smells like rotten fish when heated usually.

[@twocvbloke]

I'm not going to complain about the use of through-hole caps instead of surface-mount, I used through-hole tantalums in my A600 with the wired formed to sit as though they were surface-mount, cos I couldn't get the right surface-mount versions without buying thousands of them, which I didn't need... :P

[@eerchant]

Good job!

[@JanBeta]

Thank you! :)

[@75slaine]

Great repair Jan, well done. Another Amiga saved 👍. Was sure this was going to end with a ReAmiga series 😆

[@JanBeta]

Thanks! I anticipated this would take a lot longer (and maybe require a new board) indeed. :D

[@ianstorey1521]

Amazing 🎉

[@JanBeta]

Thanks!

[@MrFixiit]

good job jan

[@JanBeta]

Thank you! :)

[@larrylorenson7517]

On Adrian digital basement (youtube) he uses a very easy way to remove smt caps without damaging the pcb. he just twists off the cap

[@JanBeta]

Yeah, that’s the quick method. I managed to rip some pads with it in the past so I don’t use it anymore. The hot air method is the safest method in my experience, as I said.

[@ShainAndrews]

Sure... destroy your own hardware.

[@duanerobinson935]

Nice!!

[@JanBeta]

Thanks! :)

[@batlin]

Hah, did not expect the moocow emojis when using the desoldering gun but... it makes total sense.

[@JanBeta]

It was a spontaneous idea after some other retro KZbinrs referred to the desoldering gun as the "moo gun". :D

[@BerndFelsche]

I remember when one could buy "rivets" to insert into boards for repair of through-hole connections. FWIW: I think Dr Chris' employment of Lorena for cap removal seems safer for repairing old boards. Not to say that your method doesn't work for you.

[@JanBeta]

I think the replacement through-hole plating is still available. I might look into that for future repairs. It would be handy for at least some of the broken plating on this Amiga (although some spots, the surrounding traces were also ripped out, so it would be necessary to do some additional bodging anyway in this case). I'm going to have to take a look at Dr Chis' method, never heard of it. Do you have a link?

[@NeoMK27]

Hello Jan. Are you not subscribed to Dr Chris Edward’s channel? You are in for a treat if not - it’s one big rabbit hole though to fall down……

[@mancavehobbies6213]

Can i buy this of you please

[@JanBeta]

Sorry, no. I still have plans for this one.

[@RDJ134]

Another one saved!! :)

[@JanBeta]

Indeed! It was a close call I think. And I didn't have high hopes this would be salvageable. Let alone on the first try! :D

[@hollgo626]

Ok, der Rechner läuft wieder. Schön war das Board nach dem fehlgeschlagenen Recap eh nicht, schöner ist es auch nicht geworden, aber hey, wenn das Gerät funktioniert, wer schaut da schon drauf?😉

[@JanBeta]

Sehe ich genauso. Wie im Video gesagt, gibt es sicher Möglichkeiten, das ein bisschen hübscher zu gestalten, aber in erster Linie ging es mir darum, den Amiga halbwegs verlässlich zum Laufen zu kriegen. Ich war ein bisschen überrascht, dass das Teil schon nach der ersten "Runde" wiedererweckt war. :D

[@rHinosYth]

YA Amiga content!

[@JanBeta]

Yay! :D

[@jaycee1980]

In the case where the pads are ripped, i think using through hole capacitors in the way that you are using them is a perfectly acceptable repair. Sure, you could do a pad repair, but why? it's fiddly and unneccesary.

[@JanBeta]

Yeah, I think so, too. I also added some strategic drops of hot glue to the through-hole caps in the meantime and they seem to be super solid now (plus the glue should hopefully minimize the risk of the pads coming loose anytime soon).

[@dougjohnson4266]

.

[@JanBeta]

Thank you!! :D

[@mrt.7146]

Surely not Neil from the RMC, since he would've had Mark from 'Mark fixes stuff' do it .... and then that would have been FIXED 🤩

[@gothesouthway]

From my experience, the foil on some boards just fall right off when attempting to remove bad components. No shame in finding someone with real talent to help in those situations. Even then there may not be much that can be done.

[@JanBeta]

Yeah, the pads are tricky indeed, especially if there already is corrosion on the board.

[@LossMiImKraut]

Second. :-) Besides, I ain' gunna scream at you for the throu'hole cap trick. If it fits it sits ... or so. I have botched a mac board recap job by not using ESD protection. Managed to fry one of those custom chips - it goes mighty hot, so ... geeez, is there some boot I can borrow to kick myself in the wazoo for being a clumsy oaf?

[@LossMiImKraut]

Addendum: you wouldn't imagine, but I've found out what has caused that chip going hot. It was me being an oaf alright, but not due to ESD, but due to ... badumtsss ... a solder bridge beneath one of the tantalums I've soldered on instead of the leaky caps. After removing the leakies, I've had to deal with the bottom plates which had been glued on of all things. So I went a bit brutal and pried them of with a slightly beefy hand thus scraping off a bit of the protective layer. Worry not, no pads lifted, no traces broken. After removing the cap with a bit of hot air and a pair of tweezers, I 've cleaned up the pads and the exposed traces, applied some protective lacquer and resoldered the cap. And all of a sudden, the little stinker of a mainboard gave off a chime of booting. GEEEZ. Still need to kick myself in the wazoo. For being a clumsy oaf.

[@JanBeta]

Don‘t kick yourself too hard, these things just happen. (I’ve pulled off similar stuff more than once myself.) Glad you figured it out! 👍

[@AzagXul666]

I'm such a clumsy bastard, so this looks like someone doing surgery. 😂

[@Flashy7]

Not judging, but maybe. Somebody who can not replace even one through hole cap but tries to repair an A1200's surface mount caps? It is okay to make mistakes, but I usually stop after the first and try some other method, or postpone the project until I get more practice or better equipment...

[@kristoferkoessel4354]

Yeah it never hurts to take a break and work on simpler projects to get practice

[@JanBeta]

Yeah, probably would have been a good idea to practice on something less valuable. The through-hole caps in these Amigas are particularly non-trivial to desolder so I don’t blame anyone for messing those up, even if they had practice on other boards.

[@kristoferkoessel4354]

@@JanBeta Yeah although I can’t imagine it’s easy to work on an Amiga, the solder joints are pretty small compared to stuff I see usually in amplifiers and studio modulation

[@JanBeta]

@kristoferkoessel4354 It’s a multi layer board, too, with internal layers for voltages and ground that suck up a lot of heat. Pretty tough to get the solder to melt all the way through, even more so in case there already is corrosion.

[@kristoferkoessel4354]

@@JanBeta Man I heard the batteries on the amiga can be an absolute pain as no one in the right mind actually changed the Varta batteries before they leaked, I own an ams dmx computer controlled delay for music production and it actually takes the same varta batteries that leak funnily enough. I don’t know if the A 1200 has a varta but I know the 2000 does and it leaks horribly from what I’ve seen. I can’t imagine cleaning corrosion like that so I swap the 150 mA Vartas every two years, good luck to you!

[@Blitterbug]

How the hell... Someone have their soldering iron set to nuclear mode?? Yes it's a hard job but that's catastrophic damage.

[@jaycee1980]

Wow. I dont understand why people carry on trying to do the job when they are causing damage... surely thats the time to realise you can't do the job properly and STOP. No doubt the through hole capacitor pads/ through hole plate was removed due to not enough heat used. Yes, not enough heat. I usually preheat the area around the through holes on the back of the board before desoldering with my desoldering station. If they have damaged the through hole plating, thats going to be bad as the A1200 is a 4 layer board.

[@JanBeta]

It's always a good idea to practice with something useless before attempting to work on an Amiga, I guess. I stripped quite a few obsolete DVB-T tuners and broken routers for practicing surface mount desoldering/resoldering. :D

[@jaycee1980]

@@JanBeta Exactly what I did too :)

[@Breakfast_of_Champions]

🐮🐮🐮!!!

[@andrejgerbec8645]

God, what a mess 😂

[@JanBeta]

Glad I could fix this poor thing.

[@psteier]

First :D