The component you are unsure about is a crystal, normally used for a specific frequency oscillator reference. It looked like you were measuring the resistance of the pot while the unit was powered up which is a NO NO. NEVER measure resistance of a component while power is applied to the board as you will possibly damage your meter, the board or both.
I got a black Dreamcast from Best Buy for 50 bucks back in 2001. Definitely worth the purchase. I played the absolute hell out of that thing and it still works like new today. Meanwhile my PS2 and Xbox all broke within a few years.
A tip from an electronic engineer: when you're measuring the resistance with the DMM (digital multimeter), the resistor/potentiometer mustn't be powered. That's because the DMM imposes an adjusted current into the resistor, it reads the voltage drop across the resistor itself and after that uses the Ohm law to calculate the resistance. If that resistor is powered up, another current is adding to the adjusted current from the DMM, so the reading is far off! Edit: that cilindrical thing that you couldn't identify (in the disc unit board) is a crystal oscillator
@Brandon Kick If you are testing individual component resistance than I believe you would be correct. I have never checked/set laser pots, but I do know whenever there is power to the system this will throw off the DVOM's reference voltage it uses to check resistance.
Love the show vince. True though: Always turn off to test resistance. The multimeter will test resistance by feeding a small current through the circuit. This current and any current coming from the dreamcast will interact. Not only will the reading be wrong but you could potentially also damage the dreamcast.
It's almost impossible to do resistance checks with the part in circuit as external components will affect the readings. Parallel resistances !!! However the potentiometer readings he had from the Internet were probably taken with the pot in circuit so although not accurate to the individual pot we're usable for reference in circuit measurement only.
Hey Vince, I believe you really need to test and swap the OTI-9220 chip, which is the big square chip at the back of the board where you did replace caps. This chip is actually the GD-ROM controller itself. It does control spinning, tracking and focus among other things.
Oh OK, I looked online but I couldn't find any information. Maybe I can revisit this one again if I can get hold of one of them OTI chips. Thanks for sharing this info, after spending so much time on this it would be nice to get it working :-)
My worry would be that if I take the chip from the good CEX dreamcast and then damage the chip and I can't buy a replacement then I would be left with 2 faulty Dreamcasts. I changed the chip on the video because I knew you could buy them really cheaply online :-)
@@Mymatevince You can also oversolder OTI legs, sometimes its 1-2 leg with bad conection (have got lucky few times). But it is likely Hespelf is right and that damn chip is faulty.
Not sure if this was mentioned by anyone else but you can't do ESR readings with caps still on the board. Other devices like inductors and what not will affect the reading. You would have to remove a pin or remove the cap to do the test properly. Same thing with doing resistance readings as well. Which is why testing for voltages is your best friend.
You can buy RGB cables, composite cables, and VGA cables (or make your own like I did). As the laser diode ages it starts to weaken to the point it cannot read a disc. Some people tweak the laser voltage using the potentiometer on the drive PCB but if that works it wont last long. You are better trying to replace the laser unit completely. The best way to adjust the laser voltage is with an oscilloscope - probe the RF pad and adjust based on the eye pattern displayed. You can see an example of how to do that in some of the CD system repairs I've done (PC Engine CD-ROM, Amiga CD-32, Saturn, PS1 etc). The big problem with the Dreamcast is there are few 'new old stock' lasers left I think. You can fit an "SD Card" drive emulator into these too - to replace the drive with an SD card. Suprising you found that it appears the original laser is OK! That's quite rare! I would be looking at the SMD caps next on the drive controller board. It could also be a fault with the BTL / H-bridge driver chip - maybe focus or tracking related. The caps on the drive PCB are electrolytics (just surface mounted) - so your replacements would work. The voltage rating won't affect anything as you say (as longer as they are higher voltage rather than lower). Worth getting some molycot onto the gears and mechanical parts on these - they really grind away when they get dry. The other thing I would point out is (and this is only advice - everyone has different ways of doing things, its just my opinion!) - Don't solder chips like that with hot air - use hot air to remove it, then clean the pads up with braid on the PCB, then put the new chip on there (if its an old replacement chip, use braid and flux on the underside of the legs first to remove any solder on the legs), then position it, use the soldering iron to 'tag' diagonally opposite corners. Inspect the chip placement to make sure its the right way around and all pins aligned. Then use some good flux (chip qwik) and drag solder manually. You would get better connections that way! Very interesting to see that the chip worked OK on the 'working unit' though - that rules that out. When it was trying to spin it sounded incredibly noisey to me - I would be inspecting / lubricating the gears and stuff, maybe swap out the motor to see if that has a relation to the problem too. Sorry I've posted pages of text here lol. The point where the drive is hitting the edge over and over - looks like you found the switch wasn't working there? That is critical so the drive logic knows its at the start of the disc. Did you check all your cap connections were OK, and that the replacement ribbon was OK too at that point? The component that you didn't know what it was (silver cylindrical with 2 pins) is a crystal.
The reason adjusting the laser isn't really a nice fix is if you have to move it by more than a few %, that proves the laser is actually dieing. Typically a laser will output its optimum value for 90% of its life and then gradually drop, increasing the voltage overdrives it to output at 100% again, which means its life will shorten as a result as it gradually drops even faster to a point where it won't read again. If you needed to adjust a very small amount (eg. by less than 5%), you may get a few years out of it. It's frustrating when people 'tweak' these though and then sell them on as 100% working, because they just won't last.
No need to apologise Chris, pages of text means plenty of info so that is good. I should be apologising for the length of the video but this failed fix went on and on and on. I thought I did the caps OK but maybe when I was removing the surface mount ones I might have damaged a pad. Pretty sure the ribbon cable was fully pushed in. I might dig this Dreamcast out again as this video was actually done a couple of months ago and check it over again. I had an interesting message from hespelf, here it is "Hey Vince, I believe you really need to test and swap the OTI-9220 chip, which is the big square chip at the back of the board where you did replace caps.This chip is actually the GD-ROM controller itself. It does control spinning, tracking and focus among other things." This could be the problem. I had a quick look on Google for the OTI chip and didn't find any for sale but I only looked for a couple of minutes. I didn't check the SMD caps on the drive board. I haven't heard of Molycot but if it works on various different plastic gears then I will get some. The old 1979 BigTrak that I got working in another video could use some of that as well :-) With the drag soldering I did have a little bit of practice on the PS4 from hell so in future I will try and get more used to it :-) After the advice you gave on the MegaJoy2000 (N64 controller with the NES games) I now recognise that component as a crystal. Thanks for the advice on the laser, I thought it may be a short term fix. I think I will revisit this one :-) Cheers for the help and tips.
@@Mymatevince rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F253726296640 Better than gdrom more cost effective than getting a working replacement gdrom drive The device listed above plugs directly into where the gdrom plugs in This allows you to get your broken dreamcast up and running without a working gdrom
Thanks for the video, it's interesting to watch your adventures trying to fix all of this broken hardware. Your narrative feels like story telling, really good. So, if you turn a pot too much, then kiloohms turn into killerohms and kill the laser :)
An easy test for laser activity Vince.. pop a sheet of tissue paper over the laser which means you can look at it without risking your eyes...plus the paper will diffuse the laser light and illuminate (assuming usually red for CD) if the laser is functioning. rgds Evan
Thanks Vince. You prove again that you would go further than I would, I would have written it off as a bad laser but you proved it to be a fault on the board. I must learn to dig deeper when fault finding. I love your videos but one thing that really bugs me, and this should be taken as advice and not a put down is that when you say "killer ohms" it should be "kilo ohms". Keep up the good work.
if you ever need to look directly at the laser light in the future and your worried about what it might do to your eyes you can use your phone's camera to view the laser because it can't reproduce the exact wavelength of the laser.
Best thing about the Dreamcast Vince not sure if anybody has mentioned yet but the ability to play copied games was a huge plus! Saved so much money! Soldier of Fortune great game for the Sega Dreamcast!
There are several mods that can be done on the Dreamcast, one of them being an SD card reader in place of the GD-ROM drive. Keep it for yourself and replace the GD-ROM with an SD card reader. You can also replace the stock fan with a high performance fan, as well as other case mods.
@@Lonngridgeway yeah you can use .GDI or .CDI files but you need to format the card as FAT32 and the folders have to be named like music tracks "01 ; 02 ; 03 ; etc." and the disc image files have to conform to the legacy 8.3 file naming scheme to properly boot. add the games you want and then use folder 01 for the GD EMU boot disc and from there you can select and pick the games with names/album art you want to play.
This is why having a 3d printer to create broken and missing parts makes this job so much better. A lot of people create the parts and share them online
I just noticed something. I'm not sure if it's like that on the Dreamcast laser too, but usually with potentiometers, the two pads that are close together on the same side, are the right and the left side of the wiper You're moving while turning the pot and the single padis connected to the wiper itself. So to take any meaningful measurements where you see changes, you measure between the right side or left side of the wiper and the wiper itself.
Older video but I appreciate how you post your failures as well as your successes. Well, not ever really a failure when you get to learn but you know what I mean. A lot of other channels will only post what they've successfully fixed and that's a bit disingenuous, IMO. Anyway, I hope you had better luck with this since.
A very interesting video! just a few things in case you fancy doing a dreamcast again :D The capacitors you removed are surface mounted electrolytic, replacing them with through hole radial electrolytic is fine it's just a little ugly in comparison but if it works it works, make sure to never plug in a dreamcast controller whilst the system is turned on, it has a high tendency to either break the controller or break the dreamcasts port board by blowing it's capacitors (or the resistors in the controller). If you ever come across dreamcasts that are listed as turns itself off after a while thats another very common fault, when the system gets hot the metal pins connecting the power supply to the motherboard expand and short out, they also often get corroded or dirty so you just need to polish them, re-tension the clasps on the connector and bend the pins back gently towards the rear of the console. As for GD-rom drives they are notoriously fickle and spares are unavailable as they only ever got used in dreamcasts and the sega naomi arcade machine, typically it's the laser that dies so its very odd to have the drive board be faulty, I'd be interested in you installing the ISO loading drive replacement devices though.
Thanks for all the tips. I just Googled the ISO loading drive replacement and the very quick look I had was showing them for sale at £70ish. I will have another look later to see if cheaper alternatives are available on eBay :-)
i was cringing when he was replacing those caps with different type... when you get to Amiga's please make sure you replace the caps right or u have whole community after you ! ha
That cylinder component about 1 hour and 5 min into the video is a crystal for timing. On the other board it had a surface mount one fitted so that could cause problems if faulty also heat affects the value if faulty . If you have Hz or FREQ symbol on the multimeter you might be able to read the value. Falling that you could give chris a bell he's pretty clued up with type of thing. Good luck with the repair 👍🏻
When it comes to the dreamcast and reading disks, I think one of the tips you can employ is checking the settings and seeing if auto start is on. it may actually save you (or anyone) a lot of headaches. IF auto start is OFF then the game won't auto load when you're in the dreamcast main menu (or when the system is powered on) I believe this also stops the disc from spinning AFTER the " please wait reading disc" message although I could be wrong.
Hey vince, just a heads up, use cut led leads attached to the alligator clips for more accurate esr readin. When you add legnth to the cable you add resistance.
Wasn’t just the PS2. It was part of it yes but after. Biggest was money. Just wasn’t getting back what they were spending making it etc. still a good system though.
That postage thing reminds me of the time I bought my typewriter for 30$ with free shipping, the guy paid 40+$ on shipping so the guy I bought it from pretty much lost money
That silver cylinder you point to at the end might be a quartz oscillator crystal. It could of possibly blown out. Try swapping them and see if they work.
In interested in that to because he paid no attention to it. VINCE WE NEED A REVISIT!! your in quarantine nows the time. Get that silver cylinder tester or swap it out from the working dreamcast.
I’m watching this also three years later and the cylinder “crystal oscillator” at time stamp 1.04:56 near c126 is attached at two points and on the other board time stamp 1.04:47 near c126 black rectangular chip is attached at four points . I bet that “cylinder” crystal oscillator was put in in an attempt to repair it and it is wrong. If I recall the board with the rectangular black chip at c126 is the new working one. You might as well swap that if you still have them. Good luck
Another really good fix it video vince....... im really enjoying your channel .......thankyou for taking the time and sharing... i find all your videos interesting and entertaining....
Hi. When you put that chip onto the 'bad' board, make sure that you cleaned the flux off completely. I built a kit with some surface mount components recently, and until the flux was cleaned off completely, the board I built did not work. Just a thought.
Louis Rossmann is a good go-to guy to watch for micro-soldering and he uses a micro-soldering pencil for touching up small solder joints :) they also sell "hot tweezers" for taking off small resistors and capacitors.
I find your logic when troubleshooting very similar to my own thinking, very entertaining to watch for some reason! It does however baffle me when you get stuck on an idea that has no reasoning to it whatsoever and I think you even know yourself that its a lost leader but continue with it anyway. Perfect example was your playing with the lid switch at the beginning of this one, you know its not going to have an effect how much you press it as its either working or it isn't (on or off) which you prove in seconds but then stay faffing with it for another 5 -10 mins for no reason, these vids could be a lot shorter and easier to watch if you took out these moments... just my 2 cents! keep up the great vids matey :)
Ofcourse this was entertaining to watch, I know nothing about fixing things but i love to watch it. Always if you post a trying to FIX video, in the beginning of those video's i'm full of excitement, is he gonna fix it this time ? And if not i'm like " Ooh, at least we learned something about it :D So, yes even if it is a "Fail", for me it's still entertaining.
Check to see if the wires hooked up to the switch that control the laser movement is broken. If you need any parts vince I have plenty. I have been doing video game system repair since 2001.
Funnily enough I've fixed a Dreamcast that had the exact same issue, I just replaced the gdrom board with a spare though so I never really bothered to fault find it.. I wonder what causes them to go bad. Congrats on fixing it though, Dreamcasts are neat little game consoles!
Haven't tested myself with an actual CD-ROM/DVD-ROM laser BUT with an optic fiber you can check the light using the camera of your smartphone. It's a nice trick which I use from time to time when connecting servers for a fibre card.
Hoped right till the end you were going to fix this🥺 The reason the disc stops is because the CPU is not receiving days from the laser so it defaults to motor stop. Since the laser is good the problem must lie in the coding/encoding bitstream and nothing to do with the motor speed.
I love watching you try to fix these sorts of devices. I think it'd be a hell of a video for you to pick up a nitro RC off eBay and get *that* running again.
@@Mymatevince Unexpected reply, but hah, nice to bump into another RC nut. Hmm, perhaps you can find a suitable bash spot to run them that won't piss anyone off? Maybe a friend that's got access to a farmer's unused field or a football pitch that would allow it? Hell, if there wasn't an oversized mud puddle in the way I'd even offer up my own yard for it, I run my own there all the time(IN fact I ran two of them just yesterday) and I'm rural enough that nobody gets annoyed by the racket. I would suggest tinkering with electric RCs but it really wouldn't make a very interesting video if one of them is bought broken and resuscitated like it would coaxing an old engine back into life. Anyway, keep up the awesome repair vids. I love seeing things get fixed that most people would just discard and replace.
I didn't read anyone mention it, but you are not supposed to plug and unplug controllers into a DC when it's on. There is a fuse in the controller port board that can blow which will make the controllers not able to communicate with the console. Something about the power for the VMUs.
Im glad your doing a dreamcast, you can use av cables which is far better quality and it has dialup internet but can be upgraded to a broadband which was only available in japan and maybe the u.s.
Wow dreamcasts are loud ! I'm not sure about the dreamcast, but in optical disc based systems, when the drive doesn't seem to work, it's almost always the laser which is at fault. More modern drives won't spin the disc until the laser has focus on it, which usually causes people to assume the motor is at fault when it's the laser. The motor is easy to test and pretty much never fails anyway ! One thing I do know about the dreamcast however, is that the controllers are not "hot-swappable" ! This means that they should not be plugged in / plugged out while the dreamcast system is turned on , it can do damage to the controller and the dreamcast ! So always be sure to have the system turned off before change controllers. Great video as alway Vince ! :)
That little silver cylinder you could not identify was a crystal. Looked post production because of the solder joints on it. May have been needed to balance that circuit after inspection. Some components do look different in that area.
Hey Vince maybe check the height of the spindle with the working one as sometimes they can be pushed down over the years. I know that's a common fault on the Saturn. In the past I would just raise the spindle with a pair a pliers. Obviously if the disc is the wrong height it wont read.
That is one thing that I didn't think to check, someone else mentioned a possible faulty chip so I might look into that and also compare the height to see if it is possible to get it working again. Thanks for sharing the tip :-)
Hey Vince, my hunch is that it thinks there isn’t a disc in the drive. Whatever signal gets sent to tell it to keep spinning the disc/that there is actually a disc in the drive isn’t being sent so it just stops the disc spinning as it thinks nothing is there. Maybe the port the ribbon cable goes on has a loose connection/solder on bad board that isn’t putting data to it so it thinks no cd is in it?
Dreamcast does have online play and servers are even still up today to play Dreamcast online. There is a simple to put together device called the Dreampi that lets you play Dreamcast online using modern internet connection. Dreamcast also supports 480p video over VGA so video quality is pretty high, you don't want to use a cheap RF video cable.
Just wanted to comment Vince regarding the capacitor values. You highlight the value being the same but the voltage not mattering as long as same or higher. That’s not true, you can get away with a small increase in voltage value but you need to be able to charge the dielectric plates, and if the value is too high which 6.3v to 25v is the capacitor will not work correctly. Also when measuring capacitors, remove them from the board otherwise you are measuring the capacitance of the circuit not the capacitor itself. Hope that’s helpful. Additionally, those capacitors you removed from the board are SMD electrolytics same as the discrete ones but smaller 👍 the component which you pointed to at the end of the video is a crystal, used for clock pulse for timing. You would need an oscilloscope to check it for the sine wave.
You have a working unit -- that is great. Get a cup of tea, notepad and Fluke and begin taking measurements on both units, and write them down. When you find different readings, investigate. When you have no schematics or test point data, this technique really helps to find a next step. Cheers
Vince - try bridging the lid switch to always closed and see what happens. The lid switch not making proper contact (due to grime build up) is the cause of a lot of problems similar to this. The solution is to take the switch apart and clean it.
Hi Vince, I know this video has been out there 11 months or so and you may have had this suggested before. Have you considered buying yourself a lab/workbench isolation transformer? it would make things far safer for you when you have items in bits with 230V going in. also you can use them although its not the true purpose to lower mains to 100v or so when testing imported products from us etc. Just thought I'd mention it enjoying the vids all the best Sean
Damn..I really wanted this fix to work. Was on the edge of my seat ready to shout "Result!" during the last 20 mins or so! Oh well. You win some you learn some. Cheers Vince
When you wanted to change the chips around I was thinking it’s a bad idea. Just be happy you have 1 working Dreamcast. If it ain’t broke then don’t fix it. Just asking for trouble.
sometimes simply touching the soldering iron on the pins of the chips to re flow the solder can fix a problem.iv'e never tried it with a dream cast though.
The nostalgia! THS NOSTALGIA!! I still have my dreamcast, the very first consol i had snd dtill love it till this day, the only severe fault with it ive had was myself
That dreamcast laser mechanism was so noisy it would alert you to an incoming battle in Skies of Arcadia. The transition sounds would startle you if you didn't have that split second drive noise warning.
DreamCasts were really noisy little boxes. Sega probably could have afforded to make it a little bigger, if it meant the sound factor could have been muffled. Still, a great, little internet browsing machine for it's day. (No anti-virus needed. No HDD or solid state chips to save virii in.)
1:31:47 That looks like a quartz crystal oscillator, though from what I could see from the video I could not find any information about the component by searching on the component number, and going off on some of the clock frequencies (master and those based off of other clock frequencies) in the DreamCast I could find on the internet, I was also unable to find a logical speed the oscillator would be responsible for (measuring the oscillator frequency with an oscilloscope might prove to be difficult, since some of the oscillator frequencies can be up to a 100 Megahertz and it would require a very expensive oscilloscope to be able to measure that). If you have a scope, have you measured the incoming power of the drive controller for distortions? The laser head jamming itself against the end of it's reach looks/sounds like a controller that's absolutely confused because of a power supply feeding it high-frequency rubbish it perceives to be the switching voltage it tries to correct (and fails) or makes it fail becoming stable for operation. This is also commonly seen in TFT's TV's when the power supply goes bad and the boards supplied by it can't start up properly, even though when you get a multimeter out you will probably read a reasonably stable whatever voltage you might expect to find going off on voltages printed on the PCB or the datasheet, but when looking at those same power lines with a scope they might be "contaminated" with high frequency interference. I also found a pretty interesting guide that talked about "sleepy crystals" (not sure if it applies to every quartz crystal from every manufacturer, but I'm reasonably sure it does) and could make their resistance go higher than wanted when the appliance it is in has been left unused for a good while and could be solved by making the crystal experience "hard mechanical shock" or being "driven hard electrically" (I assume the last while being removed from the board).
at 1:13 you are measuring 2 ohms equivilent series resistance, not the capacitance but out of spec anyway. these caps are known to go bad and often leak etching the traces away
I know this is ancient history now, but if you still have both GDROM boards you could run through and get diode readings from the good board (positive to a ground point, and negative probe to test points) and then compare these to readings from the bad board to scope down where the problem is. I was hoping you were going to get to the bottom of it!
I have a dreamcast that won't read discs either, a gear on the motor that moves the laser assembly got cracked and won't move it back and forth anymore, its hardly noticeable to the naked eye, but it is there. And the Dreamcast does have a visible laser light as i looked up the potentiometers too, but i decided not to adjust it.
Love your tenacity Vince. Not sure if I missed it, but did you try the bad board on the good Dreamcast after doing the recap and chip swap? If it works on the good Dreamcast, then it might suggest the laser or the motor itself is faulty? Sorry if you already tried that combination; I was half watching and tinkering in my workshop so I might have missed it!
Nice and very patient work. Love the way the desk gets messier and messier as the vid goes on. A bit like my kitchen table lol. I don't own a Dreamcast and no expert on lasers but, fwiw, I think you were on the right track. Maybe need to seat that chip down properly by taking it of, wicking the solder off the pads, seating the chip flat and trying again by drag soldering it. Maybe just wait for the new chip to be sure as you don't want to damage the pads. It looks to me like when you changed the chip the behavior changed radically. Maybe one of the pins was linked to the endstop switch and isn't now connected so it doesn't realize it has hit the end? You lost nothing changing the caps. They were on the way out anyway and would have eventually damaged the board by leaking electrolyte which can eat through traces. Keep it up and don't throw it across the room .... yet lol ;)
FYI if you use your mobile phone camera you can see led's here is a tip try your tv remote control. Turn on your phone camera and point your tv remote at it you will see the led light up unless your remote is faulty or batts are dead.
Inspect the internals Of the unit before connecting to the MAINS SUPPLY ⚡as an Example, metal pieces or metal screws rattling around can cause SHORT CIRCUIT'S and make the job an even more expensive repair.also get yourself an ESD Lead as (Electrical static Discharge) can damage ESD Sensitive components if handled. You will need a service manual to determine (voltage value readings) as its pointless guessing as you need to know the correct voltage read outs at each rail to determine any power shortages 👍. When a game is detected you will hear a clearable beep from the unit as the laser spins
Hey Vince...Nice video now that you are buying more old devices you should try also that process to clean and return the original color from the plastic.... Like for example the Guy from "the 8-bit Guy" does...
The component you are unsure about is a crystal, normally used for a specific frequency oscillator reference. It looked like you were measuring the resistance of the pot while the unit was powered up which is a NO NO. NEVER measure resistance of a component while power is applied to the board as you will possibly damage your meter, the board or both.
I got a black Dreamcast from Best Buy for 50 bucks back in 2001. Definitely worth the purchase. I played the absolute hell out of that thing and it still works like new today. Meanwhile my PS2 and Xbox all broke within a few years.
A tip from an electronic engineer: when you're measuring the resistance with the DMM (digital multimeter), the resistor/potentiometer mustn't be powered. That's because the DMM imposes an adjusted current into the resistor, it reads the voltage drop across the resistor itself and after that uses the Ohm law to calculate the resistance. If that resistor is powered up, another current is adding to the adjusted current from the DMM, so the reading is far off!
Edit: that cilindrical thing that you couldn't identify (in the disc unit board) is a crystal oscillator
Thanks for the tips :-)
...when you're measuring the resistance with the digital multi meter (DMM), the resistor...
Exactly!!
I love the honesty of this restoration channel. He is not an expert and also not assuming to be. I subscribe.
A failure? Sir your tenaciousness is inspiring!
You cannot do resistance checks with power to the circuit. It will throw all the readings off.
@Brandon Kick If you are testing individual component resistance than I believe you would be correct. I have never checked/set laser pots, but I do know whenever there is power to the system this will throw off the DVOM's reference voltage it uses to check resistance.
I was thinking that the entire time he was doing that
Love the show vince. True though: Always turn off to test resistance. The multimeter will test resistance by feeding a small current through the circuit. This current and any current coming from the dreamcast will interact. Not only will the reading be wrong but you could potentially also damage the dreamcast.
Hopefully he sees this comment/thread.....Liked.
It's almost impossible to do resistance checks with the part in circuit as external components will affect the readings. Parallel resistances !!! However the potentiometer readings he had from the Internet were probably taken with the pot in circuit so although not accurate to the individual pot we're usable for reference in circuit measurement only.
Hey Vince, I believe you really need to test and swap the OTI-9220 chip, which is the big square chip at the back of the board where you did replace caps.
This chip is actually the GD-ROM controller itself. It does control spinning, tracking and focus among other things.
Oh OK, I looked online but I couldn't find any information. Maybe I can revisit this one again if I can get hold of one of them OTI chips. Thanks for sharing this info, after spending so much time on this it would be nice to get it working :-)
My worry would be that if I take the chip from the good CEX dreamcast and then damage the chip and I can't buy a replacement then I would be left with 2 faulty Dreamcasts. I changed the chip on the video because I knew you could buy them really cheaply online :-)
@@Mymatevince You can also oversolder OTI legs, sometimes its 1-2 leg with bad conection (have got lucky few times). But it is likely Hespelf is right and that damn chip is faulty.
@@Mymatevince Isn't the CEX one under warranty ;-) ;-) I'm sure no one there watches youtube j.k
@@jmarynicz Just what I was thinking! Whack the knackered board in and take it back for a replacement, cex probably bought it for £5 anyway lol ;)
"It's quite loud." Haha, welcome to the Dreamcast ;)
Not sure if this was mentioned by anyone else but you can't do ESR readings with caps still on the board. Other devices like inductors and what not will affect the reading. You would have to remove a pin or remove the cap to do the test properly. Same thing with doing resistance readings as well. Which is why testing for voltages is your best friend.
You can buy RGB cables, composite cables, and VGA cables (or make your own like I did). As the laser diode ages it starts to weaken to the point it cannot read a disc. Some people tweak the laser voltage using the potentiometer on the drive PCB but if that works it wont last long. You are better trying to replace the laser unit completely. The best way to adjust the laser voltage is with an oscilloscope - probe the RF pad and adjust based on the eye pattern displayed. You can see an example of how to do that in some of the CD system repairs I've done (PC Engine CD-ROM, Amiga CD-32, Saturn, PS1 etc). The big problem with the Dreamcast is there are few 'new old stock' lasers left I think. You can fit an "SD Card" drive emulator into these too - to replace the drive with an SD card.
Suprising you found that it appears the original laser is OK! That's quite rare! I would be looking at the SMD caps next on the drive controller board. It could also be a fault with the BTL / H-bridge driver chip - maybe focus or tracking related. The caps on the drive PCB are electrolytics (just surface mounted) - so your replacements would work. The voltage rating won't affect anything as you say (as longer as they are higher voltage rather than lower). Worth getting some molycot onto the gears and mechanical parts on these - they really grind away when they get dry.
The other thing I would point out is (and this is only advice - everyone has different ways of doing things, its just my opinion!) - Don't solder chips like that with hot air - use hot air to remove it, then clean the pads up with braid on the PCB, then put the new chip on there (if its an old replacement chip, use braid and flux on the underside of the legs first to remove any solder on the legs), then position it, use the soldering iron to 'tag' diagonally opposite corners. Inspect the chip placement to make sure its the right way around and all pins aligned. Then use some good flux (chip qwik) and drag solder manually. You would get better connections that way! Very interesting to see that the chip worked OK on the 'working unit' though - that rules that out.
When it was trying to spin it sounded incredibly noisey to me - I would be inspecting / lubricating the gears and stuff, maybe swap out the motor to see if that has a relation to the problem too. Sorry I've posted pages of text here lol. The point where the drive is hitting the edge over and over - looks like you found the switch wasn't working there? That is critical so the drive logic knows its at the start of the disc. Did you check all your cap connections were OK, and that the replacement ribbon was OK too at that point?
The component that you didn't know what it was (silver cylindrical with 2 pins) is a crystal.
The reason adjusting the laser isn't really a nice fix is if you have to move it by more than a few %, that proves the laser is actually dieing. Typically a laser will output its optimum value for 90% of its life and then gradually drop, increasing the voltage overdrives it to output at 100% again, which means its life will shorten as a result as it gradually drops even faster to a point where it won't read again. If you needed to adjust a very small amount (eg. by less than 5%), you may get a few years out of it. It's frustrating when people 'tweak' these though and then sell them on as 100% working, because they just won't last.
No need to apologise Chris, pages of text means plenty of info so that is good. I should be apologising for the length of the video but this failed fix went on and on and on. I thought I did the caps OK but maybe when I was removing the surface mount ones I might have damaged a pad. Pretty sure the ribbon cable was fully pushed in. I might dig this Dreamcast out again as this video was actually done a couple of months ago and check it over again. I had an interesting message from hespelf, here it is
"Hey Vince, I believe you really need to test and swap the OTI-9220 chip, which is the big square chip at the back of the board where you did replace caps.This chip is actually the GD-ROM controller itself. It does control spinning, tracking and focus among other things."
This could be the problem. I had a quick look on Google for the OTI chip and didn't find any for sale but I only looked for a couple of minutes.
I didn't check the SMD caps on the drive board. I haven't heard of Molycot but if it works on various different plastic gears then I will get some. The old 1979 BigTrak that I got working in another video could use some of that as well :-)
With the drag soldering I did have a little bit of practice on the PS4 from hell so in future I will try and get more used to it :-)
After the advice you gave on the MegaJoy2000 (N64 controller with the NES games) I now recognise that component as a crystal. Thanks for the advice on the laser, I thought it may be a short term fix.
I think I will revisit this one :-)
Cheers for the help and tips.
@@Mymatevince
rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F253726296640
Better than gdrom more cost effective than getting a working replacement gdrom drive
The device listed above plugs directly into where the gdrom plugs in
This allows you to get your broken dreamcast up and running without a working gdrom
Looks great but the price is really high. I will do some research into it as a lot of comments have mentioned it. Thanks for the link :-)
@@Mymatevince absolutely no worries bud item well worth it keep up awesome content
I love how much you try and how in depth you go !!!! I'm same with cars have to know the fault
Thanks for the video, it's interesting to watch your adventures trying to fix all of this broken hardware. Your narrative feels like story telling, really good.
So, if you turn a pot too much, then kiloohms turn into killerohms and kill the laser :)
An easy test for laser activity Vince..
pop a sheet of tissue paper over the laser which means you can look at it without risking your eyes...plus the paper will diffuse the laser light and illuminate (assuming usually red for CD) if the laser is functioning.
rgds
Evan
Thanks Vince. You prove again that you would go further than I would, I would have written it off as a bad laser but you proved it to be a fault on the board. I must learn to dig deeper when fault finding. I love your videos but one thing that really bugs me, and this should be taken as advice and not a put down is that when you say "killer ohms" it should be "kilo ohms". Keep up the good work.
if you ever need to look directly at the laser light in the future and your worried about what it might do to your eyes you can use your phone's camera to view the laser because it can't reproduce the exact wavelength of the laser.
I will be sure to remember this.
You can use any digital camera to look at the infra red laser because it is near infra red. You can also see the infrared from your TV remote.
Vince desperately needs to learn how to edit. ALL his videos are waaaaaaaaaaaaaaaaaaaay too long.
or get special laser operating googles. They are a thing and come with specialist and high power hobby handheld lasers
@@SDMF5000 but thats good more content to enjoy
God bless your wife. She seems to be supportive of your desire for knowledge. Allowing you to buy another Dreamcast just to learn more about them!
To true but don't think it's about allowing he's a grown man more supporting of his hobby.
@@laylajonesCD That statement has been made by someone who obviously isn't married! ;-)
This must be cuckest comment i ever have seen
In case you need ribbon cables, you can find them in old CD-ROM's and usually they fit in consoles that have optical unit. Great video as always
Your tenacious approach to fixing, or attempting to fix things is fantastic.
Best thing about the Dreamcast Vince not sure if anybody has mentioned yet but the ability to play copied games was a huge plus! Saved so much money! Soldier of Fortune great game for the Sega Dreamcast!
There are several mods that can be done on the Dreamcast, one of them being an SD card reader in place of the GD-ROM drive. Keep it for yourself and replace the GD-ROM with an SD card reader. You can also replace the stock fan with a high performance fan, as well as other case mods.
Bingo! That's what I'd do with it!
@@Lonngridgeway
Yes. I believe you can use GDI files as well as CDI.
Simply plop them on the card and put them in the system and you're good to go :)
@@Lonngridgeway yeah you can use .GDI or .CDI files but you need to format the card as FAT32 and the folders have to be named like music tracks "01 ; 02 ; 03 ; etc." and the disc image files have to conform to the legacy 8.3 file naming scheme to properly boot. add the games you want and then use folder 01 for the GD EMU boot disc and from there you can select and pick the games with names/album art you want to play.
I like your curiosity approach to fixing stuff.
Another interesting video, I have always had an interest in electronics, but never gained any general knowledge, with these videos I'm learning a lot.
This is why having a 3d printer to create broken and missing parts makes this job so much better. A lot of people create the parts and share them online
I really admire your persistence Vince!
I just noticed something. I'm not sure if it's like that on the Dreamcast laser too, but usually with potentiometers, the two pads that are close together on the same side, are the right and the left side of the wiper You're moving while turning the pot and the single padis connected to the wiper itself. So to take any meaningful measurements where you see changes, you measure between the right side or left side of the wiper and the wiper itself.
Eventhough it was a fail to fix video I really enjoyed every minute of it thanks vince come back to it when you got time
Thank you :-)
Older video but I appreciate how you post your failures as well as your successes. Well, not ever really a failure when you get to learn but you know what I mean. A lot of other channels will only post what they've successfully fixed and that's a bit disingenuous, IMO.
Anyway, I hope you had better luck with this since.
i hope there’s a part 2 this was really interesting
mate you have the patience of an absolute saint. awesome work again dude.
I've worked on many of the North American models. I'm 19 turning 20, I'm from the US and I absolutely love them!
A very interesting video! just a few things in case you fancy doing a dreamcast again :D
The capacitors you removed are surface mounted electrolytic, replacing them with through hole radial electrolytic is fine it's just a little ugly in comparison but if it works it works, make sure to never plug in a dreamcast controller whilst the system is turned on, it has a high tendency to either break the controller or break the dreamcasts port board by blowing it's capacitors (or the resistors in the controller). If you ever come across dreamcasts that are listed as turns itself off after a while thats another very common fault, when the system gets hot the metal pins connecting the power supply to the motherboard expand and short out, they also often get corroded or dirty so you just need to polish them, re-tension the clasps on the connector and bend the pins back gently towards the rear of the console.
As for GD-rom drives they are notoriously fickle and spares are unavailable as they only ever got used in dreamcasts and the sega naomi arcade machine, typically it's the laser that dies so its very odd to have the drive board be faulty, I'd be interested in you installing the ISO loading drive replacement devices though.
Thanks for all the tips. I just Googled the ISO loading drive replacement and the very quick look I had was showing them for sale at £70ish. I will have another look later to see if cheaper alternatives are available on eBay :-)
@@Dan-TechAndMusic certainly best not to have to fix this problem if you don't cause it in the first place :D
i was cringing when he was replacing those caps with different type... when you get to Amiga's please make sure you replace the caps right or u have whole community after you ! ha
That's the dumbest design flaw I've ever heard.
I am really enjoying this video, have not reached the end yet, but those capacitors that were removed were Surface mount electric capacitors.
1:31:35 r118 looks like a crystal for timing I think, but location number id is r118 meaning resistor. tough fix.
Looks like a crystal to me. Used as a reference / oscillator for one of the chips.
That cylinder component about 1 hour and 5 min into the video is a crystal for timing. On the other board it had a surface mount one fitted so that could cause problems if faulty also heat affects the value if faulty . If you have Hz or FREQ symbol on the multimeter you might be able to read the value. Falling that you could give chris a bell he's pretty clued up with type of thing. Good luck with the repair 👍🏻
These videos are fascinating! Keep 'em coming!!
When it comes to the dreamcast and reading disks, I think one of the tips you can employ is checking the settings and seeing if auto start is on.
it may actually save you (or anyone) a lot of headaches.
IF auto start is OFF then the game won't auto load when you're in the dreamcast main menu (or when the system is powered on)
I believe this also stops the disc from spinning AFTER the " please wait reading disc" message although I could be wrong.
i am going to recommend for older electronics that you use proper ESD protection. modern electronics are fairly immune to it, but older stuff is not.
Hey vince, just a heads up, use cut led leads attached to the alligator clips for more accurate esr readin. When you add legnth to the cable you add resistance.
I still really love the Dreamcast even though it failed when the PS2 released, but nice work on the Dreamcast Vince!
I love your fix it videos!
Wasn’t just the PS2. It was part of it yes but after. Biggest was money. Just wasn’t getting back what they were spending making it etc. still a good system though.
your right. :)
That postage thing reminds me of the time I bought my typewriter for 30$ with free shipping, the guy paid 40+$ on shipping so the guy I bought it from pretty much lost money
Lmaoooo
That silver cylinder you point to at the end might be a quartz oscillator crystal. It could of possibly blown out. Try swapping them and see if they work.
i think that's what it is, because thats how it controls everything, the motor and the frequency of the laser, it's all from that crystal
In interested in that to because he paid no attention to it. VINCE WE NEED A REVISIT!! your in quarantine nows the time.
Get that silver cylinder tester or swap it out from the working dreamcast.
I’m watching this also three years later and the cylinder “crystal oscillator” at time stamp 1.04:56 near c126 is attached at two points and on the other board time stamp 1.04:47 near c126 black rectangular chip is attached at four points . I bet that “cylinder” crystal oscillator was put in in an attempt to repair it and it is wrong. If I recall the board with the rectangular black chip at c126 is the new working one. You might as well swap that if you still have them. Good luck
You are a very persistent person on projects. Really really good. Excellent fault finder. Great work Vince and very informative.
Another really good fix it video vince....... im really enjoying your channel .......thankyou for taking the time and sharing... i find all your videos interesting and entertaining....
Hi. When you put that chip onto the 'bad' board, make sure that you cleaned the flux off completely. I built a kit with some surface mount components recently, and until the flux was cleaned off completely, the board I built did not work. Just a thought.
Louis Rossmann is a good go-to guy to watch for micro-soldering and he uses a micro-soldering pencil for touching up small solder joints :) they also sell "hot tweezers" for taking off small resistors and capacitors.
I find your logic when troubleshooting very similar to my own thinking, very entertaining to watch for some reason! It does however baffle me when you get stuck on an idea that has no reasoning to it whatsoever and I think you even know yourself that its a lost leader but continue with it anyway. Perfect example was your playing with the lid switch at the beginning of this one, you know its not going to have an effect how much you press it as its either working or it isn't (on or off) which you prove in seconds but then stay faffing with it for another 5 -10 mins for no reason, these vids could be a lot shorter and easier to watch if you took out these moments... just my 2 cents! keep up the great vids matey :)
not necessarilly bad.
it only adds to the interaction
between audience and entertainment imo.
longer video to sit through and enjoy a sandwitch.
“It’s not worth dying over a Dreamcast.” Great line.
CheatingSoi He's wrong though haha!
Oh you bet it's worth it
What about a Dreamcast 2?
Oh it's worth every breath if you can get it working
Dreamcast 2 aka Xbox.
Ofcourse this was entertaining to watch, I know nothing about fixing things but i love to watch it.
Always if you post a trying to FIX video, in the beginning of those video's i'm full of excitement, is he gonna fix it this time ? And if not i'm like " Ooh, at least we learned something about it :D So, yes even if it is a "Fail", for me it's still entertaining.
Check to see if the wires hooked up to the switch that control the laser movement is broken. If you need any parts vince I have plenty. I have been doing video game system repair since 2001.
Funnily enough I've fixed a Dreamcast that had the exact same issue, I just replaced the gdrom board with a spare though so I never really
bothered to fault find it.. I wonder what causes them to go bad. Congrats on fixing it though, Dreamcasts are neat little game consoles!
Haven't tested myself with an actual CD-ROM/DVD-ROM laser BUT with an optic fiber you can check the light using the camera of your smartphone.
It's a nice trick which I use from time to time when connecting servers for a fibre card.
I fell asleep watching a guy fix 12 PlayStations 4 and woke up to you fixing this
Did you ever revisit this, Vince? 1.5hrs of my life gone and it’s still broken!!! I need closure 😩
Probably a dumb question, but did you tested the new ribbon cable on the working system?
Hoped right till the end you were going to fix this🥺
The reason the disc stops is because the CPU is not receiving days from the laser so it defaults to motor stop. Since the laser is good the problem must lie in the coding/encoding bitstream and nothing to do with the motor speed.
First to say 👋 just wanted to say I really enjoy your videos and keep up the great work.
I love watching you try to fix these sorts of devices. I think it'd be a hell of a video for you to pick up a nitro RC off eBay and get *that* running again.
Don't tempt me...I love RC stuff. The noise of the Nitro would get me in trouble with the wife and the neighbours though :-)
@@Mymatevince Unexpected reply, but hah, nice to bump into another RC nut. Hmm, perhaps you can find a suitable bash spot to run them that won't piss anyone off? Maybe a friend that's got access to a farmer's unused field or a football pitch that would allow it? Hell, if there wasn't an oversized mud puddle in the way I'd even offer up my own yard for it, I run my own there all the time(IN fact I ran two of them just yesterday) and I'm rural enough that nobody gets annoyed by the racket. I would suggest tinkering with electric RCs but it really wouldn't make a very interesting video if one of them is bought broken and resuscitated like it would coaxing an old engine back into life.
Anyway, keep up the awesome repair vids. I love seeing things get fixed that most people would just discard and replace.
It was a valiant effort, you can't beat them all. I'm sure you still got some knowledge from it.
I didn't read anyone mention it, but you are not supposed to plug and unplug controllers into a DC when it's on. There is a fuse in the controller port board that can blow which will make the controllers not able to communicate with the console.
Something about the power for the VMUs.
Im glad your doing a dreamcast, you can use av cables which is far better quality and it has dialup internet but can be upgraded to a broadband which was only available in japan and maybe the u.s.
Wow dreamcasts are loud !
I'm not sure about the dreamcast, but in optical disc based systems, when the drive doesn't seem to work, it's almost always the laser which is at fault.
More modern drives won't spin the disc until the laser has focus on it, which usually causes people to assume the motor is at fault when it's the laser. The motor is easy to test and pretty much never fails anyway !
One thing I do know about the dreamcast however, is that the controllers are not "hot-swappable" !
This means that they should not be plugged in / plugged out while the dreamcast system is turned on , it can do damage to the controller and the dreamcast ! So always be sure to have the system turned off before change controllers.
Great video as alway Vince ! :)
Thank you for the tip :-)
That little silver cylinder you could not identify was a crystal. Looked post production because of the solder joints on it. May have been needed to balance that circuit after inspection. Some components do look different in that area.
really enjoyed the video m8. As always great job.
every time i watch one of vince's vids i feel like watching another episode of hyouka.
Hey Vince maybe check the height of the spindle with the working one as sometimes they can be pushed down over the years.
I know that's a common fault on the Saturn. In the past I would just raise the spindle with a pair a pliers. Obviously if the disc is the wrong height it wont read.
That is one thing that I didn't think to check, someone else mentioned a possible faulty chip so I might look into that and also compare the height to see if it is possible to get it working again. Thanks for sharing the tip :-)
Hey Vince, my hunch is that it thinks there isn’t a disc in the drive. Whatever signal gets sent to tell it to keep spinning the disc/that there is actually a disc in the drive isn’t being sent so it just stops the disc spinning as it thinks nothing is there. Maybe the port the ribbon cable goes on has a loose connection/solder on bad board that isn’t putting data to it so it thinks no cd is in it?
I've always had good luck adjusting the height of the spindle, the part where the disk clips in. It's just on with pressure.
fixed a boombox that way once!
Dreamcast does have online play and servers are even still up today to play Dreamcast online. There is a simple to put together device called the Dreampi that lets you play Dreamcast online using modern internet connection. Dreamcast also supports 480p video over VGA so video quality is pretty high, you don't want to use a cheap RF video cable.
Just wanted to comment Vince regarding the capacitor values. You highlight the value being the same but the voltage not mattering as long as same or higher. That’s not true, you can get away with a small increase in voltage value but you need to be able to charge the dielectric plates, and if the value is too high which 6.3v to 25v is the capacitor will not work correctly. Also when measuring capacitors, remove them from the board otherwise you are measuring the capacitance of the circuit not the capacitor itself. Hope that’s helpful. Additionally, those capacitors you removed from the board are SMD electrolytics same as the discrete ones but smaller 👍 the component which you pointed to at the end of the video is a crystal, used for clock pulse for timing. You would need an oscilloscope to check it for the sine wave.
I've got 5 Dreamcasts. But then again i am a SEGA nut. Brilliant console way ahead of its time. Hope you get a fix for it M8. 👍
Was a underrated console you can get an cables and they tend to be noisey maybe not that noisey hope it works out in the end
Segaaaaaa
I thought the fridge repair was interesting but this is the best video of the year, so much excitement and action!
You have a working unit -- that is great. Get a cup of tea, notepad and Fluke and begin taking measurements on both units, and write them down. When you find different readings, investigate. When you have no schematics or test point data, this technique really helps to find a next step. Cheers
Vince - try bridging the lid switch to always closed and see what happens. The lid switch not making proper contact (due to grime build up) is the cause of a lot of problems similar to this. The solution is to take the switch apart and clean it.
Hi Vince, I know this video has been out there 11 months or so and you may have had this suggested before. Have you considered buying yourself a lab/workbench isolation transformer? it would make things far safer for you when you have items in bits with 230V going in. also you can use them although its not the true purpose to lower mains to 100v or so when testing imported products from us etc. Just thought I'd mention it enjoying the vids all the best Sean
if the laser stops reading, reduce the resistance. Resistor on the laser head, spin it a little bit, try 700ohm, 650ohm and so on
Damn..I really wanted this fix to work. Was on the edge of my seat ready to shout "Result!" during the last 20 mins or so! Oh well. You win some you learn some. Cheers Vince
When you wanted to change the chips around I was thinking it’s a bad idea. Just be happy you have 1 working Dreamcast. If it ain’t broke then don’t fix it. Just asking for trouble.
Another great video from another great Legend with a special loving care for the device Dreamcast but it's failed miserably
Hi Vince great video nobody can say that you give up easily
The rf modulator you could buy separtley the dreamcast came with composite cables
"Right, although this sounds like a silly thing to do, I've looked online..."
keep in mind that by the time the dreamcast came out, there were no lcd tv screens. the thing is purely made für CRT, thats where it really shines!
Not true it had native vga support too
sometimes simply touching the soldering iron on the pins of the chips to re flow the solder can fix a problem.iv'e never tried it with a dream cast though.
The nostalgia! THS NOSTALGIA!! I still have my dreamcast, the very first consol i had snd dtill love it till this day, the only severe fault with it ive had was myself
I think the lil odd capacitor the long one looks like a replacement at sum point so worth to test and replace
That dreamcast laser mechanism was so noisy it would alert you to an incoming battle in Skies of Arcadia. The transition sounds would startle you if you didn't have that split second drive noise warning.
DreamCasts were really noisy little boxes. Sega probably could have afforded to make it a little bigger, if it meant the sound factor could have been muffled. Still, a great, little internet browsing machine for it's day. (No anti-virus needed. No HDD or solid state chips to save virii in.)
1:31:47 That looks like a quartz crystal oscillator, though from what I could see from the video I could not find any information about the component by searching on the component number, and going off on some of the clock frequencies (master and those based off of other clock frequencies) in the DreamCast I could find on the internet, I was also unable to find a logical speed the oscillator would be responsible for (measuring the oscillator frequency with an oscilloscope might prove to be difficult, since some of the oscillator frequencies can be up to a 100 Megahertz and it would require a very expensive oscilloscope to be able to measure that).
If you have a scope, have you measured the incoming power of the drive controller for distortions? The laser head jamming itself against the end of it's reach looks/sounds like a controller that's absolutely confused because of a power supply feeding it high-frequency rubbish it perceives to be the switching voltage it tries to correct (and fails) or makes it fail becoming stable for operation.
This is also commonly seen in TFT's TV's when the power supply goes bad and the boards supplied by it can't start up properly, even though when you get a multimeter out you will probably read a reasonably stable whatever voltage you might expect to find going off on voltages printed on the PCB or the datasheet, but when looking at those same power lines with a scope they might be "contaminated" with high frequency interference.
I also found a pretty interesting guide that talked about "sleepy crystals" (not sure if it applies to every quartz crystal from every manufacturer, but I'm reasonably sure it does) and could make their resistance go higher than wanted when the appliance it is in has been left unused for a good while and could be solved by making the crystal experience "hard mechanical shock" or being "driven hard electrically" (I assume the last while being removed from the board).
at 1:13 you are measuring 2 ohms equivilent series resistance, not the capacitance but out of spec anyway. these caps are known to go bad and often leak etching the traces away
I know this is ancient history now, but if you still have both GDROM boards you could run through and get diode readings from the good board (positive to a ground point, and negative probe to test points) and then compare these to readings from the bad board to scope down where the problem is. I was hoping you were going to get to the bottom of it!
I have a dreamcast that won't read discs either, a gear on the motor that moves the laser assembly got cracked and won't move it back and forth anymore, its hardly noticeable to the naked eye, but it is there. And the Dreamcast does have a visible laser light as i looked up the potentiometers too, but i decided not to adjust it.
Love your tenacity Vince. Not sure if I missed it, but did you try the bad board on the good Dreamcast after doing the recap and chip swap? If it works on the good Dreamcast, then it might suggest the laser or the motor itself is faulty? Sorry if you already tried that combination; I was half watching and tinkering in my workshop so I might have missed it!
Thank you, yes the problem was definitely on the bad board, the laser and motor is fine :-)
Nice and very patient work. Love the way the desk gets messier and messier as the vid goes on. A bit like my kitchen table lol. I don't own a Dreamcast and no expert on lasers but, fwiw, I think you were on the right track. Maybe need to seat that chip down properly by taking it of, wicking the solder off the pads, seating the chip flat and trying again by drag soldering it. Maybe just wait for the new chip to be sure as you don't want to damage the pads. It looks to me like when you changed the chip the behavior changed radically. Maybe one of the pins was linked to the endstop switch and isn't now connected so it doesn't realize it has hit the end? You lost nothing changing the caps. They were on the way out anyway and would have eventually damaged the board by leaking electrolyte which can eat through traces. Keep it up and don't throw it across the room .... yet lol ;)
Thanks, I will need to have another look at this Dreamcast as since the video a viewer mentioned that one of the legs was loose on the chip I did :-)
Looks like the switch u was on about not turning laser off or on maybe ?
Great vid kept me entertained for an hour and a half ,I have still got my original Dreamcast still works as well.
1:22:19 pin moved when you pushed on it by the b Maybe that's the switch not working
That is dedication though systematic dismantling and reassembling to fault find.
Hey Vince, you can try to remove the disc drive and replace it with an SD card reader and do re-visit video! Love your content, thank you!
FYI if you use your mobile phone camera you can see led's here is a tip try your tv remote control. Turn on your phone camera and point your tv remote at it you will see the led light up unless your remote is faulty or batts are dead.
Inspect the internals Of the unit before connecting to the MAINS SUPPLY ⚡as an Example, metal pieces or metal screws rattling around can cause SHORT CIRCUIT'S and make the job an even more expensive repair.also get yourself an ESD Lead as (Electrical static Discharge) can damage ESD Sensitive components if handled. You will need a service manual to determine (voltage value readings) as its pointless guessing as you need to know the correct voltage read outs at each rail to determine any power shortages 👍. When a game is detected you will hear a clearable beep from the unit as the laser spins
Hey Vince...Nice video
now that you are buying more old devices you should try also that process to clean and return the original color from the plastic....
Like for example the Guy from "the 8-bit Guy" does...