Sorry some of the video is a little dark. With regards to removing chips with hot air, you can see an example in a previous PC Engine repair video:- ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-V1h5d7pXI24.html
Just got my 5th TG16 today and the seller also described those marks as “burns.” Sure enough, I found oily spots everywhere that a cable was touching, like when I moved the RF switch cable off of the RF switch. It’s really bad where the cables push down into the softened plastic, which had happened to the console shell at some point. Almost all of my TG16 consoles have those deep melted cable marks including some of my RF switches and other accessories. Someone on NintendoAge recently mentioned that his has those marks. I told him it was caused by plasticizers/plastic-softeners in the cable jackets. Suddenly other long-time collectors chimed in to say that they had the same problem and never realized this was causing it. Because people don’t know, a lot of collectors will unknowingly make it worse by packing their stuff away with cables contacting the plastic. Thanks for spreading awareness!
My CoreGrafx I has those ball bearings too.I thought it was for extra grip to what ever is plugged in to the ext.bus. port. I took opened up my Core Grafx I apart for a little inspection and I think it was the first time it was opened. The screws had that initial crack feel when unscrewing and the screws had little bits of plastic in the thread. I've been talking to a friend whose PC Engine only gets a white screen when turning on but we cant find a possible cause. After watching this video, the white screen could be the same chip you replaced. Great work as usual and very informative.
I would suggest he gets a copy of Space Harrier! My first PCE just gave a white screen, yet it would boot Space Harrier (and display nothing). I believe Space Harrier boots, loads stuff into RAM, starts the audio section playing the title music, then waits for a hblank, and that never happens when the GPU has completely failed. So it could help him identify the cause. If it doesn't boot, and voltages are OK, I would suggest either the 6280 (CPU) or WRAM.
GadgetUK164 - Retro Gaming Repairs & Mods Maybe Blazing Lazers too? I’ve got a TG16 that was described as “doesn’t boot” but I tested with Blazing Lazers and you can *hear* everything. It seems to boot, but it just boots to a blank screen. I left the attract mode demo loop running and one stage actually shows graphics (third loop of the title screen; 100% consistent). It looks like faded white pixels only but I can see the monochrome sprites and some of the level (bubble that change size so not exactly part of the background layer). It may work there because of the different color pallet that level uses, which made me pretty sure it was the HuC6260 VCE (Video color encoder) until I saw your video. I’ll check for an overheating 6270 and reflow everything. :)
I've had exactly the same remark on one of my videos lately about the plastic burn marks being caused by cables wrapped around a console. I too said in my video that I thought it could have been caused by a soldering iron. I like these PCEngine consoles because they're so small and powerful at the same time.
I have a tip for you Chris. White vinegar is good for removing surface rust from shields, you can soak the shield for a couple of hours while you're doing the repair on the system, it will stop the rust in its tracks. I'm RGB and 50/60 Hz modding a Sega Master System 2 at the moment with a rusted top shield. I have video of that fix and the mod coming soon.
Waiting patiently my own hot air desoldering station to arrive safely home, videos like this is giving me ideas! A perfect fix for a magnificent console! Well done again! :-)
Good call on the hot glue. Some of those dock pins push in with the normal force of being docked. I got a junk lot of three TG16 consoles recently. I straightened the pins on one and realized that it was pushing in most of the way with each insertion. I was testing with the official Turbo-CD dock because the original RF jack was broken off the modulator and I needed an alternate AV output (dock has composite). It works great but I obviously can’t let that pin bend back and forth like that. It’s a middle pin too so it’s probably shorting to a pin for the top row. Just need to find my GameBit drivers. :) It turns out that two of the three are perfectly functional except for broken RF jacks and you’ve given me a lead on what to do about the third one. Score! The third one was described as “doesn’t boot/blank screen” but you could hear Blazing Lazers boot and I was able to get monochrome graphics on at least one level. It was consistent too: just let the attract mode blindly loop through the title screen/intro three times and I’d see graphics on a particular stages it demonstrates. I suspected the HuC6260 VCE (Video Color Encoder) since it seems to be visible due to that stage’s color pallet and, well, there are still color anomalies. Since your VCE seemed fine and had an extremely similar issue I’ll definitely be looking for a HuC6270 and reflowing everything first. Hopefully I’m wrong since my source is out of 6260 but does have some of the other chips I might need, including 6270. :) Curious: you say your source no longer has HuC6270. Who was it? I’ll definitely share my source after I get done diagnosing but if it turns out I need a 6260 maybe they have that... or a better price on the chip I need. Can’t say my source so publicly just yet since I might be ordering their last one, but I know you’ve heard of ‘em!
Yes, it might seem a bit crazy using hot glue that way, but there really aren't many options to stop a "weakened" pin being push straight back in after pulling it out. And yes, that one that has music and sound but no graphics, sounds like the 6260. I have seen that black and white issue like that related to the 6270 though. I think my source was the Hong Kong Video Game Doctor.
Nice upload GadgetUK, I love these PC Engine videos. I got that SNES working with the CPU replacement finally, and a hoard of 6 boards from ebay to work on now :) Fibreglass pen added to my shopping basket, another great tool I don't have... Thanks for continued great content and advice.
Got another two working already! A PPU2 causing yellowish tinge to the picture on one, and one was covered in what looked like flux but must have been coca cola or something, super sticky when cleaning. Loads of isoprop later, a new fuse, and another success. So satisfying. Got a third with black and white picture, going to try replacing the crystal oscillator give the red screw a tweak... If that doesn't work ill be asking for help! =D
I suspect that someone spilled some coke or coffee and never checked if it went their consoles. Got a Core II myself from back in the day, but some store modded it (might have been console connections), drilled a hole in the right side to have a hard wired SCART lead coming out.
It’s totally amazing that we buy these things for about 200 bucks. The amount of technology is amazing in these things. Mass production is the only way to make these things cheap. How did the core graphics do in Europe? Is gaming big in Europe?
The PC Engine is very popular in europe now! But when these systems sold back in the 1990s, they didn't sell very well. We had the Turbo Grafx 16 (European and US versions) - which didn't sell anywhere near as well as the Super Famicom or Megadrive.
Good job you had a spare graphics chip there, I need to get used to the idea of soldering surface mount chips like that, it looks scary but you make it look so easy lol. I wonder if somebody spilt coke or something on that thing, it did look like a horrible brown liquid had dropped on it.
Yeah, I'm not so sure about it being flux, although flux does go a yucky brown colour, they would have had to have been really sloppy to get it all over the place like that.
These PC Engines often have that flux all around the chips there! Open up any white PCE or Core Grafx and typically it will be there around all the chips =/
I just opened up a Core Grafx 2 I got from Japan, and its motherboard was also covered in a flux-like brown residue! Do you have any clue what's going on with that? Did NEC have some really sloppy manufacturing process with the CG2? I wiped as much as I could off with IPA.
Great stuff Chris, not sure if this is a solution you'd ever consider but a few machines ive had with those gouges, i've used a scouring pad (the fibre one not metal) and been able to buff/smooth them out a bit, even removed some of the shallower ones.
That's a technique that can work well! I did a similar thing on a video yet to upload on the edge of the case, to flatten the damage etc. It can work well! =D
The 8/16 pin looks like an 8-bit/16-bit bus selector. If it's in 16-bit mode and was disconnected then it's likely that only the 8-bit registers worked correctly. It could explain why the intro didn't look right but while playing the game it was fine. The intro could be using the GPU in 16-bit mode while the game was using it in 8-bit mode probably to lower CPU usage for a more intense gameplay and graphics with tons of sprites and other things going on.
Yes, it does doesn't it! I don't think that was the issue though since its normally tied to 5v, and I believe if it slipped into 8 bit mode the graphics wouldnt have displayed correctly at all (since they are 16 bit). The problem was the SPBG pin I think.
Sorry to kinda hijack one of Your videos again... This one, comparing the Core Grafx II to my PC-Engine V.1, gave me an idea why Core Grafx II's are considered to be better when it comes to jailbars: Better shielding and the shielding being connected to the IFU-30, if you have one, via those spring loaded balls at the bottom of the Core Grafx II, which connect to grounding plates on the IFU-30. So I built my own shielding inside the PC-Engine V.1, using mainly copper tape and doublesided foam tape, when the copper tape needed to be pushed onto a contact area. I had no idea if this would make any difference at all but had a hunch the extra shielding and being connected to a common ground would.... And it did! Way better than any doucoupling capacitor mod I did before, which helped a bit too though. So we've been barking up the wrong tree the whole time for the most part? Here's the result and my "modwork" asri.imgbb.com/
Hey there Chris, do you know of a source for Hu62*0 chips nowadays? I have a PC Engine unit which only boots to a yellow screen regardless of what I try.
Makes you wonder how those marks actually appear doesn't it - I mean, is it because they are in a really hot and humid location where the plastic is softer or something? Or is there some huge pile of PCE systems with cables around them in a massive pile, and the weight and pressure of systems above causes the friction to occur?
I am wondering if you can really rule out the address lines? It seemed to me a palette was not loaded (the pixel data existed, otherwise you wouldn’t see the outline either), which is a specific write to a part of the memory. I’m not 100% up to speed regarding programming the PCE’s, but every other system I programmed works that way. Would also explain a reflow making it work again
It could be, I did wonder during editing, but the one thing that makes me think its not the addressing was reading this document:- www.emulatronia.com/doctec/consolas/pce/vdcdox.txt Whilst it talks about the tile having a pointer to a palette, I couldnt quite see how we would end up with totally black sprites if one data bit or one address bit was missing. The other issue here is that every game uses that VRAM in different ways - so addressing wouldnt behave exactly the same. If a conneciton on the databus was missing, the sprites wouldnt even look right I think. That was why I assume it was a control signal, perhaps that SPBG one (something related to toggle between sprites and background tiles?) - that may account for it.
It also seems to suggest the HuC6260 holds the palette data. But if the 8 bit bus between the 6270 and 6260 had a bit missing, the video would be really messed up.
Yeah, I never noticed before but if you look at the connections between the 6260 and the 6270 there are 9 bits! It has an 8 bit data bus I think, and that 9th connection is SPBG - must be to do with palette selection. I cannot be sure without testing that theory, but its the best bet I think. Useful when things like this happen though, because I learn more about the hardware. If I ever see a PCE with palette issues, I would know where to look now - probably the DAC, but I would probe that connection to check its toggling.
And looking back at that point where I went around the chip pinout there - CK was obviously clock! So there's very little other connections I think could have caused it. I am convinced SPBG was the issue!
Instead of using an air compressor to blow out Connectors I would highly recommend using a Paint brush that is "25mm to 30mm" or if yo Be Merry Can "1 inch" wide that is liberally dipped into IPA 99% Alcohol, it has to be the good stuff that will evaporate within minutes, There is never a time when too much IPA is a bad thing, when cleaning circuit boards that have inadvertently been given some coffee ;) well it looked like coffee, ANYWAY.. Air Compressors introduce a vapour onto surfaces that if missed can do more harm, specially ones that don't get daily purges that expel the water that builds up in them. One more thing, Invest in some Chrome or Silver Spray Paint, Failing that, You could use Matt Black Spray Paint by masking off contact areas to whatever shields, once sprayed, remove masked areas and if possible tin and clean the contact areas from flux followed by a deoxidising agent before reassembly.. Dropped a Iike Bro Err-Boss..
could it have been the connection to whatever pin carries the blue channel data for the graphics issue seen when you replaced the gpu? the jewels in lords of thunder were green when you were having the issue, but blue when it was fixed. also, with the rf shield, can you put something on to re-protect the corroded parts again?
It wasn't a specific colour bit - I believe it was the SPGB connection, the upper bit of the video data bus that is used to send palette data (as well as display output) to the DAC. So either the palette hadn't been initialised, or it was using the wrong palette. I suspect it had no palette, just whatever happened to be already set. That's why most games I tested it was just a solid black sillouette. Wiping with something like WD40 will protect it, so provided you get the rust off there it tends to not start rusting again. I've got systems I've done this with 5+ years ago here and they are still fine.
oh ok - i thought the silhouetting might have been because they were dark/shadowy figures which might have been using a lot of the blue channel to display. out of curiosity, do you know what colour is displayed if that channel is lost? eg if blue is the predominant colour (hardly any red or green) in the image - would it show as black or white? the monitor has to interpet the loss of such information in some way, doesnt it?
It works the same way as primary colours are mixed in the real world - eg. if you have only red and green, you will see yellow. www.quora.com/Will-mixing-of-red-green-and-blue-colours-give-white-colour
Would it be possible to actually tin the rusted part and smoothen it with the desoldering braid? Or, I have a liquid called liquid tin or something like that (I don't know the english name) which is what I use to protect etched PCB-s... you dip stuff in it and it covers it with a nice layer of tin. I'm not sure however if it would work for anything else but copper...but would be worth a try maybe...
You could do something like that - assuming the corrosion was cleaned off properly and flux good enough etc. But it would be incredibly hard to do as the shield will absorb a tonne of heat. Would need a very high power iron to do that. Maybe it could be treated with electrolysis?
Or that liquid tin... given that it would stick to it. I'm not sure however... If I run into something like this, I'll try it out and get back with the results :D My next patient will probably be a Sega Master System II... maybe its shielding will be a good candidate :)
I haven't tried, but one tinning option e.g. is pipe fitting solder paste - but its effectiveness on steel might be limited. It doesn't matter that the soldering iron is not up to the task, you just turn on your stove and place the part on there, that will heat it up to melt the tin and activate the paste. As far as just restoring shiny appearance of fresh steel, i think it can be done by electropolishing. But it won't be perfect because the steel sheet is originally zinc plated, and the rust wears that off. Here's an example: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-MG3i-2aruNM.html But zinc plating at home is possible too. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Wy6u2kikAA4.html
nice work. the pc engine is still one console I still need to get . a friend of mine had one back in the days and it was super fun. time to hit ebay i think :) dammit!
Hello, Your work is very very useful And I liked very much but the link with removing chips with hot air it doesn't work, when I click it opens my video manager. Anyway Keep up the good work!
I live on this video, ha, ha. Is it true using a MEGADRIVE PSU the 7805 inside the PCE converts the 9 or 10V to 5V. A therefore making the console draw only what it needs? Or is it a dick idea using a MEGADRIVE PSU?
You be careful using your magnifier in your conservatory leaving it on the floor. FIRE starter! You should never be used in a manner which could result in the Sun being imaged; if daylight is used as illumination, ensure the window faces north or away from the Sun.
I hate when the custom parts go, not like they grow on trees being donors much of the time. I have an NES with likely bad RAM chips, somebody needs to make reproductions of these chips, cars have them so why not game consoles? I'll keep fixing them until FPGA clones get cheaper. ^_^
