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About juansolo

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  • Birthday 05/01/1972

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  1. I'll save him the hassle as I knocked together the layout for him There's another one I think he's going to try out that he found also.
  2. Couple of updates. Firmware 9.0 on the PS4 has finally cured the CMOS bomb which means now that games installed on there will continue to work even if the battery fails in the future. Essentially finally stopping it bricking itself. Now all we need is for Microsoft to dial back it's DRM on the Xbone that requires every game, physical or not to verify online when installed, or if you replace a hard drive (as I did then had to re-run all 200+ games installed on the system to get them to re-verify with MS so they can run without an internet connection). That bullshit will brick those in the future so we're still waiting for them to do the right thing there. The backwards compatibility thing on PCs is a bit more awkward. For example I've a pentium/3DfX PC that will run just about everything from the 1996-2000 period where that particular setup was dominant. Beyond that there are a lot of titles that struggle. Same goes for some DOS games. In the end I've got four PCs covering various eras and with those I can run pretty much everything. The good news is that 486 era aside, they're all super cheap to put together and take up very little space. GOG definitely helps, they've got a lot of old games fettled to run in DosBox and emulating 3DfX and what have you. But there are still plenty of things we have trouble running.
  3. Not intentionally, but it is going to Muddy.
  4. Mainly we're just doing it to limit the colour drift, it's pretty cool in the UK and the other chips don't get concerningly hot. The other bits arrived also to finish number 3 (@Muddyfunster's machine). The only differences here are that it's got both Composite and S-Video out. The board mounted phono is actually just acting as a frame for a 3.5mm stereo jack running Composite and audio out. Really pleased with the jack situation on this one as it's fully removable and solid without any extra screws or anyhing.
  5. Dropped in a Asteroids/region free bios from The Brewing Academy into my own machine. Think I'm done now.
  6. Hmmm, annoyingly it looks like the Pro Controllers are no longer available from AA. That's a bummer, I'd have ordered one with the game. Bah!
  7. Galaga, Joust, Food Fight, Centipede and Asteroids for commercial. All are brilliant, beyond that you've got to go homebrew as there's way more and it's even better: Space Invaders, Moon Cresta, Asteroids Deluxe, Frenzy, Dungeon Stalker, Pac-Man Collection/40th, Froggie, B*nQ, T:ME Salvo, Donkey Kong PK, Rikki & Vikki (sadly now unnavailable). Then you've got the homebrew that's in the works: Arkanoid, EXO, Galaxian, Knight Guy, Millie & Molly, Popeye, Slideboy, etc. It's a good time to have a 7800, but limiting yourself to commercial would be missing out.
  8. Science has been happening! The heat related colour rolling thing that goes on with the PAL MARIA we decided to quantify by sticking a temperature probe to it, and taking a load of measurements. Essentially what we had observed beforehand was that the colour rolling could be stopped by heating it up with a hairdryer to a certain temperature, going beyond this temp caused the colour to start rolling the other way. For no other reason we decided to find out what those temps were and if we could get the MARIA to stay at a temp that stopped the rolling... The MARIA cold / at room temperature was 70F / 21C It takes approximately 15 minutes for the temperature to stabilise (under load) at 115F (+45F) / 46C (+25C) The 'Happy Temp', achieved with a hairdryer, where the rolling stops on this particular machine is 134F (+19F) / 57C (+11C) None of these are horrific temperatures. Indeed the MARIA was still the hottest component on the board, that includes the regulator. So we thought we'd try some ways to raise the temperature of the MARIA to see of we could get it to it's happy temp. Now obviously don't go doing this as getting ICs hot on purpose is generally a bad thing. So with a bit of foam as cladding, we could raise the temp by 11F where it once again stabilised. No matter what we tried beyond that we couldn't get it to come up the remaining 8F, concluding that it would require active heating at this point and the whole thing was getting a bit silly. Still thought it might be interesting
  9. I doubt the ones we've used would fit under. Given all the other things going on, I'd wrote off ever re-fitting the shield long ago regardless. We've enough left to drop one onto the TIA also, I'll likely do that too then. Interestingly we'll be doing some other heat related experimentation at the weekend on the PAL 7800s. Not sure where that's gonna go, but it could be fun.
  10. NTSC is sometimes lovingly called Never The Same Colour (or Never Twice the Same Colour...) and that's the next problem we've found with the NTSC 7800. We suspect this is inherently part of the problem with the NTSC standard and how it handles phase as the PAL 7800's don't have this problem. Anyhow, this is a known problem in that after a peroid of time, the colour temperature drifts until it equalises some way away from where it was initially set. Using the 7800 Utility to set the colour when cold to match the greens, our 7800's started at cool and swung all the way over to hot in terms of colour temp when compared to Trebor's templates. So in an attempt to lessen the swing, we've added a heat sink to the MARIA. This has reduced the swing and it now stabilizes at warm and never makes it over to hot. Which is nice as warm is my preferred setting as it's most like the PAL 7800. The sinks came from some old 1MB server FB-DIMMs we had kicking around that we cut to size. Stuck on with 3M heatsink tape. Also, he changed another fecking resistor on the NTSC mod, I've told him to bloody stop messing with it now. Attached. AntiJackModDocV3-4.pdf
  11. I swear, last update. More tweaking has occurred. AntiJackModDocV3-3.pdf
  12. Essentially it boils down to a few things. The NTSC and PAL 7800s are very different machines in how they go about things. Some things they do are fundamentally different and because of this, they have different problems. The PAL machine first has 3 problems which dramatically effect it's PQ. First is that the MARIA and TIA have a shared colourburst clock which causes a large amount of diagonal rolling interference. The second is that the chroma (colour) signals from the TIA and MARIA are blended and have an effect on each other even though only one is used at a time. You can set one up well, but always at the expense of the other. The final problem we were unable to find a solution for, that's a colour rolling problem that appears to be inherent on the PAL MARIA and is heat related. That one varies from machine to machine and you just might be lucky to get a better one, but they all do it to a degree. A common composite mod addresses none of these issues and will get a marginally better than RF picture. A UAV on it's own was not really designed with the PAL machine in mind. You will get an improvement, certainly by virtue of it being S-Video also (which is what the 7800 generates in essence), but again, the underlying issues are not addressed, and the UAV isn't quite as well balanced for a PAL machine either resulting it a slightly overdriven luma signal. What the French RGB machine does is take the PAL luma and chroma signals as they would have been sent to a RF modulator and sends them instead to a very simple RGB encoder. Sadly this butchers the signal and can result in sub composite quality. I'd put it somewhere around a cheap composite mod, i.e. better than RF, but not by a huge amount. If you want to encode RGB from a PAL 7800's S-Video signal it's better to do so with something external like a Canon RGB-100. The PAL machine then is a little bit of a lost cause. In the investigating PAL video issues thread above that @marauder666 posted, we went on a bit of a deep dive on the PAL probalems and came up with some solutions. They take two forms. One is an all-in-one DIY mod which is really for someone experienced with veroboard and with some skill of soldering. That can either get you S-Video or composite and it's vastly better than any current stand-alone solution. The other this we came up with is an add-on board for the UAV that deals with the chroma blending and clock issues that the AIO has built into it. If you've already got a UAV it's an easier mod, but neither are really for tack and go solderers. The NTSC machine (covered in the second thread posted above) is a vastly superior machine in PQ terms. Out of the box it's dramatically better, just dropping a UAV into it gets massively better results than all the buggering about with the PAL machine. That too had a problem that certainly irritated me, in that it had fairly bad colour fringing on certain colours. Cleggy figured out that this was a timing mismatch between the luma and chroma and came up with a fix for that. That one @-^CrossBow^- now has a board for and is a really easy drop in to fix or it's also in the doc that we did if you're ok with veroboard. Again that's not all, the NTSC machine is much more susceptable to temperature variations, we're currently having a play in that area. But to be fair, at this point the picture is just damn good and we're being picky. I've attached the current version of the doc we knocked together for anyone who wants to DIY it and CBA to read through those two threads. AntiJackModDocV3-2.pdf
  13. Moar focus, moar res!
  14. Changes are that he put a 5.1k at the bottom of resistor ladder as picture was a little dark without adjusting monitor. Reduced 820R to 390R and 1k6 to 820R on the chroma inputs. Updated below and in the doc (attached). AntiJackModDocV3-2.pdf
  15. Yeah, Cleggy is using it because he hasn't got a NTSC card for the BVM, along with the lack of S-Video card. A PVM would be cheaper, even if you could find the cards to buy, which you can't.
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