juansolo Posted August 5, 2021 Author Share Posted August 5, 2021 (edited) Seemed only right to add the NTSC all-in-one mod to the doc. I'm fairly certain no one other than us will ever use it. But at least it's documented. AntiJackModDocV3-1.pdf Edited August 5, 2021 by juansolo Typos in the doc. 1 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted August 5, 2021 Share Posted August 5, 2021 1 hour ago, juansolo said: I'd put most of it down to a crappy camera, variable room condition and me being a point'n'click photographer. In the flesh there's little to nothing in it. 7800 chroma is going through a 1.6K resistor, maybe its too high a value. PAL machine without it was oversaturated. No problem experimenting with values. Oscilloscope time to check the levels. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 5, 2021 Author Share Posted August 5, 2021 24 minutes ago, marauder666 said: 7800 chroma is going through a 1.6K resistor, maybe its too high a value. PAL machine without it was oversaturated. No problem experimenting with values. Oscilloscope time to check the levels. I'll bring both machines over on Saturday to compare/contrast. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 7, 2021 Author Share Posted August 7, 2021 We've done some back to back comparisons. On a CRT there's genuinely nothing in it that you can see. However stick it on a large LCD panel and the UAV's filtering comes into play. Where our output is unfiltered and a little sharper, we're getting noticable jailbars. Comparitively the UAV output seems softer but is more pleasant. We might add the blurring cap that we've got on the PAL version of the mod, but probably not as strong. We might experiment there. I've tried to take these pics as similarly as possible... 4 Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 11, 2021 Author Share Posted August 11, 2021 Number 3 now has a socketted BIOS, re-flowed the cart slot, joysticks ports and switches, then swapped caps/buttons/ferrite ring/regulator/power jack. I'll pull out all the video section at the weekend and start fettling the video jacks. No big hurry at the moment while The Brewing Academy is on hiatus. We tried the blurring cap and a couple of other things on our mod and they did nothing for the jailbars. Both machines are likely to end up with UAVs with the chroma shift now. 1 Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted August 11, 2021 Share Posted August 11, 2021 Did you guys design up your own PCB for the chroma fix or did you want my gerber files on the latest revision I have? Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 11, 2021 Author Share Posted August 11, 2021 33 minutes ago, -^CrossBow^- said: Did you guys design up your own PCB for the chroma fix or did you want my gerber files on the latest revision I have? You already sent them to us and we've already got 5 from JLC, cheers. At least one will end up in number 3, number 2 might get the combined relay/shift as logically it gives the purest signal (not that you can tell), and we like the satisfying click from the relays. Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted August 11, 2021 Share Posted August 11, 2021 I've made a few changes to it since then but the ones I sent will work as they are the same as the initial batch I had made up as well. They ended up being quite a bit smaller than I expected. Well, I knew what the sizes were I had in place but it wasn't until they arrived that I could really see how small the boards came out. I still need to design an SMD version to have pre-popped so I don't have to mess with them myself. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 11, 2021 Author Share Posted August 11, 2021 Nice. Honestly I doubt we'll use up the 5 we've already got. NTSC 7800s are super rare here. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 21, 2021 Author Share Posted August 21, 2021 (edited) Jailbars begone! Pic on a 20" BVM (brutally revealing) via a Koryuu that just landed (no S-Vid in on the BVM). So @marauder666 has been tweaking the all-in-one mod, it's back in the game. I'll update the doc later today with the changes. Edited August 21, 2021 by juansolo 3 Quote Link to comment Share on other sites More sharing options...
+Muddyfunster Posted August 21, 2021 Share Posted August 21, 2021 Lovely. I've been thinking of getting Koryuu transcoder to work with my OSSC as they are NTSC and PAL. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 21, 2021 Author Share Posted August 21, 2021 Back to back with mine now, the verdict is that on a BVM, they're indistinguishable. On the panel with the mod, the bars are still there but way less apparent. The filtering on the UAV softens the picture enough for them to go completely. So essentially, if you're plugging into a telly, the mod is pretty much perfect. If you're ever plugging it into a planel and you want the the best picture possible from that set up, go UAV+Shifter. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 21, 2021 Author Share Posted August 21, 2021 1 hour ago, Muddyfunster said: Lovely. I've been thinking of getting Koryuu transcoder to work with my OSSC as they are NTSC and PAL. 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. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 21, 2021 Author Share Posted August 21, 2021 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 2 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted August 21, 2021 Share Posted August 21, 2021 I've noticed the NTSC 7800 is more sensitive to temperature changes. The colours always start off cool, and then warm up. I've ended up setting the colour trimpots when the system has been on 30 minutes. Also, theres some interference on solid colours which varies with temperature, I've noticed this on ZPH 7800, and it also occurred on Juansolo's with UAV through the Koryuu. Maybe the Koryuu makes it more visible than a straight S-video connection would. This could be related to the horrible colour rolling the PAL machine has which is also temperature related. I'm going to test the Koryuu with my NTSC SNES using S-video to confirm its the 7800. As it is now, the picture on the BVM with our own s-video mod is the best I've seen from a 7800, picture was better with UAV into a panel, but I'm not using it like that. I can put up with the little interference, its 100x preferable to the colour rolling on PAL. 1 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted August 21, 2021 Share Posted August 21, 2021 A pic for @Muddyfunster 2 Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 21, 2021 Author Share Posted August 21, 2021 Moar focus, moar res! 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 23, 2021 Author Share Posted August 23, 2021 I swear, last update. More tweaking has occurred. AntiJackModDocV3-3.pdf 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 25, 2021 Author Share Posted August 25, 2021 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 1 1 Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted August 25, 2021 Share Posted August 25, 2021 9 minutes ago, juansolo said: 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. I just added new 1/2" height alum heatsinks all four of the big ICs in mine the other night. Reports of TIA chips failing when left on over night and other changes related to heat, would indicate that they old ICs aren't holding up as well as they used to with heat build up 40 years later. Can't see how tall the one is in your pic, but I went with the 1/2" so that the top RF shielding could still be used. Quote Link to comment Share on other sites More sharing options...
juansolo Posted August 25, 2021 Author Share Posted August 25, 2021 (edited) 1 hour ago, -^CrossBow^- said: I just added new 1/2" height alum heatsinks all four of the big ICs in mine the other night. Reports of TIA chips failing when left on over night and other changes related to heat, would indicate that they old ICs aren't holding up as well as they used to with heat build up 40 years later. Can't see how tall the one is in your pic, but I went with the 1/2" so that the top RF shielding could still be used. 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. Edited August 25, 2021 by juansolo Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted August 25, 2021 Share Posted August 25, 2021 On the NTSC console at least, the two hottest components seem to be the 6502 and the TIA. The TIA really only cooks when playing 2600 games though as that makes sense since more of the TIA is in use in 2600 mode. The MARIA does get warm but not nearly to the degree (pun intended) that the 6502 does. But to be on the safe side since I had them, I just added the same 40dip sinks to each. Yes it doesn't cover the entire MARIA but it covers 8/10s of it and that is enough I should think. Quote Link to comment Share on other sites More sharing options...
+Muddyfunster Posted August 25, 2021 Share Posted August 25, 2021 Probably makes sense to heatsink those two on any refurb then. I have some spare heatsinks that I picked up when I refurbed my C64, I'll check but I'd guess they would fit the CPU in the 7800. Quote Link to comment Share on other sites More sharing options...
marauder666 Posted August 25, 2021 Share Posted August 25, 2021 The heatsinks we got off the fb-dimms are 10mm high. Pleased with the picture through the Koryuu, only issue is it decodes the s-video similar to a modern display. Can’t get the correct brown ground on Commando, which I can on the little pvm through s-video. The colour drift is interesting, in that it varies so much on NTSC, PAL doesnt. PAL needs setting to warm, cool stays cool. I’d rather have the drift than the very annoying colour rolling on PAL though. Will be looking at that next, but doubt it will end up satisfactory, a very non electronic solution, might end up with a dead console. 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted September 22, 2021 Author Share Posted September 22, 2021 Dropped in a Asteroids/region free bios from The Brewing Academy into my own machine. Think I'm done now. Quote Link to comment Share on other sites More sharing options...
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