Sega Mega CD Repair (Sega CD) - Recap of Recapping

[@GadgetUK164]

It's "Kapton tape" btw =D I always miss pronounce a lot of things on my videos. eg. Scotty Diode :o)

[@RetroSalesAustralia]

Great video! Well, good and bad. The bad part is it reminded me I need to recap mine and I can't be arsed.

[@GadgetUK164]

Thanks, and hahaha - yes, that was where I was with this repair! Kept putting it off, putting it off etc.

[@Neffers_UK]

For cleaning small areas I make my own little cleaning swabs using chamois leather and wooden lollipop sticks. Trim off the end of a lollipop stick to make itsquare, sand the stick down across its width, like big fat toothpick. Epoxy the slope (not too much epoxy or the chamois will absorb it and leave a hard pad), cut a bit of chamois to fit, clamp with a peg, leave to cure. Trim off the excess once cured, and then you can use a blade to split it down its length several times to create swab sticks of varying widths.

[@GadgetUK164]

Thanks, that's an excellent idea =D =D

[@Neffers_UK]

No probs, with decent sticks you can get them really rather thin, a cheaper chamois tends to work better, seeing as they are usually a lot thinner than ones from Halfords etc. I was shown this by an old ham radio guy.

[@katakisLives]

No way I'm gonna try that! I'd bugger it up for sure! If I was to get this done I'd have to find someone online to do it

[@TheDefpom]

If it's a dual rail supply the + could go to the ground... so as long as it's not a negative supply your trick is fine.

[@electronash]

TheDefpom Normally, the silkscreen should still denote the orientation of the cap itself (or other polarised component.) So, for negative rails, the "+" of the cap may be connected to ground, but still marked OK on the board.

[@electronash]

TheDefpom Oh, I watched the rest of the vid. lol You are right for pointing that out, as a cap on a negative supply rail will have it's "+" (positive) terminal connected to ground (as we said). In those cases, checking the cap pads for continuity to ground of course won't work.

[@electronash]

(and I think the Mega CD / Sega CD might have a negative supply rail for the opamps on the "analog" board?) That would require a DC-DC converter in the unit to generate that neg rail, so I'm not sure, as I haven't looked at the service manual / schematics in a while.

[@GadgetUK164]

Thanks!!! Yes - I always miss things out and make mistakes in my videos. There are of course lots of other scenarios where it could be tricky working out which way an electrolytic goes around depending on the circuit there. But a -ve supply rail is a fairly common scenario to consider. On the logic board there I think it's all +ve, and the only negative will be related to the op amp as you say - on the little PCB at the back with power input etc.

[@GadgetUK164]

Yes, its a valid point! In general its still a good technique for that rare occasion you mess up (chances are for one cap you will be OK), and if you accidentally put it in the wrong way - it will give you a nice loud reminder of that fact later ;)

[@oldcarguy700]

Hello my Sega cd1 doesn’t play background music. On Sega cd all I hear are the jumps and coins. Main board caps are replaced and laser is new. Still nothing. Any idea? Thanks

[@GadgetUK164]

Possibly the sub board (the board that has the power connector and audio connectors) - console5.com/techwiki/images/c/c2/PC_BD_MEGA-CD_SUB_BD_171-6115C-Schematic-1_of_1.png Maybe a corroded trace around there, bad cap, bad ribbon connection to main board, or perhaps a bad DAC or opamp on that PCB!

[@oldcarguy700]

@@GadgetUK164 thank you for the reply. That’s my next plan of attack. I read that caps 3/13/14 could be bad and affecting the sound. I’m not super skilled in soldering so I may have my guy change them all out for me on that power board. Thanks again.

[@aphexteknol]

Excellent job you did cleaning up your previous "get it working NOW" repair. Really looks tidy so far.

[@GadgetUK164]

Thanks! That 'get it working NOW' repair really left me with a new opinion that temporary fudge repairs like that aren't a good idea lol. Just because I kept putting off the proper work for so long and I could have just ended up not bothering, or forgetting lol.

[@spidermcgavenport8767]

Thank you, GadgetUK164, thank you for this Sega CD recapping repair video.

[@spidermcgavenport8767]

Sir, I would be curious about the memory on the Sega Cd for saved games. Would there ever be a possibility for a mod to allow for downloading of those save files to a more modern memory mod for PC storage of game saves? I only ask this is because I do like to hexedit Eye of the Beholder and its save files. Or on the alternative allow for a cart Hexeditor type device? Theories?

[@GadgetUK164]

You can already do that if you have the Mega Everdrive! It works as a memory cart and you can copy the saves to/from the Sega CD save SRAM. I do that just to back up my saves, but it's possible to modify that save file too.

[@timstah8450]

Great Video! I enjoy your in depth explanations.

[@GadgetUK164]

Thanks =D

[@Four_X]

Always nice to revisit a console you've repaired \ modded some time back. I had one recently. It was a friends RGB modded Master System II I modded back around 2006-ish (dead z80 this time). Wow, it looked a messy inside, not my best work. I suppose your standards increase over time that and you just get better at doing repairs \ mods.

[@GadgetUK164]

Yes, I think you're right - our standards and skills do increase with every mod and repair that we do. I do find myself going back to things to perfect them recently. Sometimes I horrify myself when I look back at some bodge I did which was supposed to be temporary! I am staring to re-think the temporary repair approach lol, and perhaps I should just slow myself down and just do a proper job right from the start rather than occasionally rushing something and planning to revisit it.

[@intel386DX]

I replaced all caps and cleaned the board ,but still hangs on the BOOT screen :(

[@GadgetUK164]

You might have a damaged trace there or bad via perhaps?

[@intel386DX]

@@GadgetUK164 the pittiest thing is that the board worked normal with the old caps (I did not checked them) and after a wiele it started to glitch the screen and hangs on the boot screen. Then I noticed the lacage and replaced then and cleaned, but as I sead no change :(

[@Beaps73]

I'm not kidding, you are the reason why KZbinr of the month of certain channels is a load of bs. I can watch your vids day in day out and I never see you get the memtion/credit that you deserve. Please keep up the hobbie/hard word my man. Brilliant

[@GadgetUK164]

Thanks mate, really appreciated!!! =D There comes a point when I wonder about the value of doing these videos - I've actually skipped filming 3 or 4 things I've worked on recently, just due to lack of motivation.

[@Beaps73]

GadgetUK164 - Retro Gaming Repairs & Mods No mate please keep up the vids. I get an alert as soon as you upload a video and I'm on it like a flash. Never dull, always intriguing.

[@SianaGearz]

GadgetUK164, oh pity. I feel this is a pretty tiny community, a niche within a niche, but the more important and welcome your work is.

[@Neffers_UK]

@Gadge, please don't undermine the value of your vids, they are informative and of decent quality. In the future there could be some guy or girl tearing their hair out over something that you may have chosen not to document, no matter how simple it may seem, to them it would end a ton of frustration. Like if they searched and the guy who posted a problem to a forum, then came back and marked it as solved with no explanation as to how it was solved - one of many pet hates of the internet!

[@chadc437]

GadgetUK164 - Retro Gaming Repairs & Mods I watch all of your videos and have learned a fair amount from you. Please, keep up the great work.

[@johnny19817]

Hello. My Mega CD started buzz noises. Do you know which caps should I replace?

[@GadgetUK164]

All the caps on the logic board should be replaced on these (before they kill the system). Audio issues generally means the back sub board (the one with all the audio connectors and power connector etc) needs recapping.

[@seganutt]

update mega CD is reading audio CDS but the sound is distorted really bad but audio is fine on bios screen any idea's

[@GadgetUK164]

Have you checked the caps on the digital board - as shown in this video?

[@GadgetUK164]

Actually, thinking about it - check the caps on the audio / power board at the back as well.

[@james276]

Very neat job, Need to do the same on mine and also do the region switchless mod. Just a quick question, My Mega CD image jumps and jitters in pal mode but is fine when i switch the megadrive to ntsc. Could this be due to the lcd tv i'm using?

[@GadgetUK164]

Thanks =D That's very strange! Is your TV a european model? I could perhaps understand the TV glitching a little with sync on a PAL Megadrive switched into NTSC (since the fps ends up 59.3Hz or something daft as opposed to the 59.9 or whatever it's suppose to be. But if its a european TV, with a PAL Megadrive and you find switching into 60Hz is OK and yet 50Hz flickers - that's a bit wierd lol. That would make me wonder if perhaps the capacitor and resistor size on your scart cable could be the issue. Might be worth checking what cap and resistor on are pin 20 of your SCART cable.

[@TruthSword7]

Is it necessary to have a fume hood set up in order to do recapping work like this?

[@GadgetUK164]

It's certainly a good idea if you are doing lots of soldering, or if you are working in an area that is not well ventilated.

[@HuntersMoon78]

A fume hood is massive overkill for a recap job.

[@BrooksterMax]

Hiya, thanks for sharing does the Model 2 suffer in the same way that the Model 1 does with caps as shown here?

[@GadgetUK164]

From my experience they are much much more reliable on the model 2 CD - They tend to be through hole. You can see a photo here:0 www.the-liberator.net/site-files/retro-games/hardware/SEGA-Mega-CDII-CD-II-2/Sega-Mega-CD2/Sega-Mega-CD2-015-Motherboard.JPG

[@BrooksterMax]

Thanks kind sir, I have both models. The Model 1 is actually my original one from back in 93 from Comet! With this video and knowledge, I'll be cracking open the case and looking to take care of it now.

[@GadgetUK164]

Ahhhh, Comet! Shame they went under - I bought nearly all of my original systems from Comet - SNES, Megadrive, Amiga 500+ etc.

[@StRoRo]

Nice one. I need to open my multi mega and check it out. I also need to remove the internal battery while I'm there. I don't want that to leak.

[@GadgetUK164]

Yes - good idea on the battery! I have swapped mine out too but didn't mention it in this video.

[@StRoRo]

Is it work removing it completely or swapping it?

[@GadgetUK164]

I just swapped it for a new one! They don't tend to leak that type of cell - although they can after a very long time. I use the save support so the battery is essential for me.

[@seganutt]

Hi what size are the surface cap's u are using

[@GadgetUK164]

Mentioned early in the video there!

[@RetroConsolas_]

Great video, thanks!

[@seganutt]

i just recaped my japanese mega CD model 1 checking it after every cap i put in working ok got done to the thrid last one now control pad is not responding with the mega CD at all what have done wrong ? took the cap off again replaced it with a new thinking it be a bad cap still no good have tried 3 different japanese megadrive with it , control pad working fine with megadrive games im at a loss

[@GadgetUK164]

Sorry, I see you've recapped it lol - I've read these messages in reverse order... I would re-inspect the work you've done, look for particals of solder etc, make sure there's no flux or corrosion on there. Clean the PCB edge up too - the bit that joins the system to the Megadrive / Genesis.

[@neozeed1984]

nice work. I've gotten service manuals for sega but havn't been able to find one for pce duo.

[@GadgetUK164]

Thanks! Same here - I would love to see a PCE duo service manual! I am also still looking for a 3DO service manual, and a schematic for 2, 4 or 6 slot Neo Geo MVS.

[@Neffers_UK]

Have you tried KLOV forums for MVS related docs? Might be a long shot but ya never know.

[@GadgetUK164]

Thanks, I will try over there! I suspect there are none in public circulation because you cannot find anything in google.

[@seganutt]

Does 4x5mm sound right

[@GadgetUK164]

See at 01:00 - 3mm diameter, 5.5mm height, 10uF 16v.

[@RockstarRunner7]

The Tower of Power! Nice work, looks very tidy now. My friend is looking at my model 1 cd, some sort of poor connection issue I think.

[@GadgetUK164]

Haha - yes, thank god the master system adapter doesn't work on top of the 32x - I wonder if Sega deliberately stopped that from working that way. I've occationally had a bad connection issue with my Mega CD once or twice - they make an aweful connection to the Megadrive sometimes.

[@Nalleman79]

Great video! And thanks. Just scrolled around in youtube and found your video. Did check my megacd frontloader and lucky i did! All 10 of those 10uf were leaking bad! Ordered som new and have a nasty job ahead of me cleaning everything =)

[@GadgetUK164]

Thanks =D Glad you caught your Mega CD in time!!! Eventually that corrosion will eat through traces and can pretty much kill the Mega CD.

[@Nalleman79]

Did the job and it still work like a charm. Scary that you dont notice anything when they are leaking. Dont the picture or sound show any indication that they are leaking?

[@refractionpcsx2]

Nice job! So with SMD's like that, it's perfectly possible to just use a soldering iron? I do worry that I'm gonna get an A1200 with faulty SMD caps and I'm not gonna be able to replace them as I don't have a hot air gun lol

[@Neffers_UK]

Simple answer? Yes. Longer answer... You can get SMD "training kits" from ebay cheap. Solder a few things and see how you fare when removing them. Much better to practice on something disposable. Hot air is great for removing PLCC and similar components with many legs, but for things with two or three spots a soldering iron with your preferred tip is good enough. I'd suggest adding fresh solder to the existing solder joints before trying to remove them. Old solder can be stubborn due to oxides etc.

[@refractionpcsx2]

Thanks for the tips Neffers!

[@Neffers_UK]

No probs man. There's looads of hints and tips out there, and thanks to the interwebs, it doesn't take long to find many of them ;)

[@electronash]

RefractionPCSX2 Only problem with heating only one pad / leg at a time is that it can rip the pads up, even if you very gradually "tilt" one side of the cap while the solder is molten (and then the opposite side etc.) I've done that a few times and lifted some pads, no matter how careful I was. The "ideal" way, when the SMD parts are flat on the board, is to use a hot air station, or the two-prong "soldering tweezers", as Mr GadgetUK164 mentioned. Personally, I would NEVER recommend twisting any component off the board. It's a define no-no in electronics reworking. I would sooner recommend the snips method, but even that is less-than-ideal. (I have used that method on my own stuff, with fairly good success, but there's still a risk of ripping up pads / traces.)

[@GadgetUK164]

Yes, as Neffers and ElectronAsh have said, you can totally do it with a soldering iron. Just be careful with the removal - that's the hard part, if you can get them off without any damage, you're onto the home run. If you attempt it, just take your time and make sure you have good flux, desolder braid, and kapton tape.

[@TheHighlander71]

Some really cramped soldering there Chris. It looked a million times better afterwards.

[@GadgetUK164]

Thanks for your continued support, much appreciated =D

[@chrisw8069]

Nice work, but why use those same type of capacitors?

[@GadgetUK164]

It's true that it can be easier to solder through hole capacitors instead, but when the pads get damaged from corrosion they can have a weak connection to the PCB - so if you solder through hole caps on there, the weight of the cap can move / damage the pads - especially when the console is sent in the post etc (any knocks and the cap moves and can lift those weakly adhered pads. Plus it looks better with the correct SMD parts.

[@GadgetUK164]

And its not the case that all SMD electrolytics will leak btw - lots of caps from the 90's suffered from leaking in later years. More modern caps may or may not do that in future (I hope NOT lol).

[@chrisw8069]

I am sure they are better than the garbage from back in the day, but thanks to Sega and NEC I refuse to use SMD

[@reloadedrussty10]

Are the lasers readily available for these? I'd buy one but I don't want it to go the way of the dreamcast (no lasers)

[@electronash]

Russell Brunskill There is a replacement Samsung laser which can be made to work in the most common Dreamcast GD drives, IIRC? If they're not an exact match, I found a similar pickup before where you just had to trim one "pin" off the ribbon cable to use it. I could be wrong, but from memory, I think the part number is SPU-3200 for the replacements? (on phone atm, so a pain to check. lol) Have a search on AliExpress for "Dreamcast laser", or similar.

[@reloadedrussty10]

ElectronAsh I've actually done what you earn suggested before, I tore up some old cd-rom drives until I found a laser that worked. The problem is the actual lens is lower than the dreamcasts throwing the focus out so you need to up the power some.

[@electronash]

Russell Brunskill Ahh, fair enough. I haven't look into that stuff for quite a few years tbh. I've been too busy working on the Dreamcast HDMI and GD Emu stuff. :p

[@SianaGearz]

Drives came from two manufacturers, Yamaha and Samsung, so there's two different laser kits. I think SPU is the round one and doesn't fit half the consoles. The other is Sanyo and is super rare now, but should fit both. Don't quote me on this, I'm speaking from a long hazy memory.

[@electronash]

Siana Gearz Tell me about it. lol I've forgotten more than I've learned, in recent years. :p

[@strikermaximus365]

Led light mod would be nice

[@seganutt]

any games will not read at all this suxs i payed crazy money for it now it might be screwed

[@GadgetUK164]

Could be the laser, but if its reading audio discs I would suspect the caps on the digital board.