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It has been a LONG time since I've posted. I decided to upgrade my vertical MAME cab from an 2ghz Athlon and Windows 2000(!) to a Ryzen 5000. This thing has been going for nearly 20 years on the same version of MaLa. My front end setup is really simple, with just a Favorites and Complete lists and a simple Space Invaders moon backdrop as the background.

I've updated my gameroom and pulled stuff out of storage, so I probably don't have the time required to do the Beta justice but I'm really looking forward to progress reports and release. Thanks so much for doing this!

Edit to add: Just saw my last post was 10 years ago, and that was about MaLa too! I never ended up fully updating the machine because it was basically working find and MaLa wouldn't work with what I was considering.

Thanks for taking a look, I basically wrote a novel as to get as much detail documented as possible so no need to go through every single post.

I wasn't aware 100Ω resistors were commonly found on RGB and YUV lines. My project is done but the YUV input has always been just a bit dark, with crushed blacks while the menu overlay has always been bright. I was wondering if you ever saw that problem. At first I started using 75Ω terminating resistors like almost any other type of input mod, but the picture was way too dim, worse than it is now. So I figured the chip expected a higher signal level and did a 165Ω termination instead. Much better but the component input has still never looked 100% right. Like the signal clamp was off. Plus, I was getting some weird black streaks along the right edges of bright shapes against a dark background. I also maintained 1μF electrolytic capacitors in series and now realize ceramic disc capacitors with lower values are better to maintain the needed AC coupling, but improve frequency response a bit.

I've done RGB mods before and haven't had any such issues with the signal level, and I read where some ICs may have current limiting built in. But I'm guessing these Toshiba 88XX chips do not have that. I say that because as I was watching some DVDs last week the picture would start to drop out, but the sound would continue working. That issue got worse to the point where the picture was barely visible at all, and it affected the component and s-video inputs. So it seems something with the Y clamp circuit in the chip failed, maybe I burned it out doing this mod incorrectly.

I replaced the chip since I added a socket, then I encountered another issue where it would power on for about a second after I plugged it in then turn off and not respond. It would do the same thing regardless of what chip I put in it. I then found out I had severed the 5V rail where the keyboard connector is because the board is so cheaply made. This cut power to the microcontroller side of the chip. Glued and fixed that connection, but I don't want to re-do the component mod until I get the resistor situation corrected in case I did burn out the luma circuit in the old chip. Glad I was able to find spares on eBay for just a few dollars.

I also wanted to ask about the 391 capacitors on the cathode amplifiers, these are used for filtering according to the schematic Adrian Black on YouTube scanned in from his China kit board. He bought his in 2023, and he doesn't seem to have any blue streaking issues. I checked and the blue capacitor on mine is indeed a higher value so I'll be replacing it. I'm not sure if I'm seeing any symptom of that though. There is some noticeable smearing of the reds and blues when using s-video but that might just be chroma delay seen on these chips.

tps://github.com/misterblack1/yichuang_crt_board/blob/main/Chinese%20TV%20Board%20combined.png

Yeah I'm here. What do you want to know?

I read through the thread you linked, but didn't go back through all your old ones.

I've used a couple of those CRT kit boards before and honestly the build quality was terrible. As for the delivery, not really the manufacturers fault but, it seemed like the delivery drivers had used the boxes as footballs back at the warehouse. Despite being packed reasonably well with bubble-wrap and solid plastic frames around the chassis, both arrived with broken corners and traces from significant impacts. I got a full refund but FYI.

SO a bad experience. I rebuilt the broken traces on one of the units anyway, and got it working on a spare CRT, but yeah the quality was not there so I moved on to other projects. More parts for the spares bin. Maybe that was all part of the delivery trauma, it doesn't mean you can't get a good one, as YMMV.

I'm on Reddit too but not as active. My user name there is "Medic8ted".

I can go full desk top with a big video card. but with where I use my computer, (kitchen table) mini pc works well.I can go full pc but everything seems to have RGB lights. Not a fan of them. I do not need the bling

If you have the space, I would suggest reconsidering a small case.  Small is the current fad, but very limiting.  With these systems, you often see another (expensive) little box with a graphics card coupled to its own power supply, and external storage boxes.  So instead of a larger case, you simply get the same parts distributed across your table, sometimes with less efficient data transfers.  Cooling can also be another issue.  As for RGB, there are usually just one or two simple plugs you can unplug to get rid of them and the cost they add to the system isn't enough to be concerned about.

Your call.  But if modern gaming is what you are after, you WILL need a good GPU, and more importantly, a place for it to live.  And in that case, the GPU will be doing most of the heavy lifting.  So my recommendation is to find the middle ground.  A decent medium form-factor machine, with a CPU which doesn't bottleneck whatever GPU you need to play the games you want to play, and with enough space for a couple of 3.5" drives.  You don't need a massive "showcase" system, unless you are trying to impress someone, or seriously into local AI, where expansion at some point is almost guaranteed.  But you do need something practical to cover your bases.

On the other hand, so long as your gaming needs are not too demanding, you might get away with one of the AMD processors with the GPU on-die.  This simplifies things and puts you more in the "steambox" category of devices.  These are capable, but underpowered for the later games, especially at resolutions above 1080p.  So for the best outcome, you really need to do a deep dive into what you expect from the system, and what configuration is likely to best support that outcome moving forward.

Given the costs involved currently, it's better to plan for a PC which will cover your projected needs for the next 5 years or more.   I never thought that would be the case, but here we are

Final note:  Don't skimp on the GPU.  I have experimentally shoehorned an RTX 5060ti 16gb onto a pretty crap HP t740 Thin Client.  Not crap with regard to what that little machine was intended for, but specifically for this type of use.  However, with that configuration, I have been able to play older PC titles like Black-ops II at 4k cranked to the max, under Linux no less, at a solid 60fps.  So my takeaway is that if gaming is the goal, you only need enough processor and RAM to manage current and possibly future GPU requirements.  Think like you are building a dedicated gaming console, not a general purpose machine.  It will easily perform most general purpose tasks, once you reach the gaming goal.  Good luck! 

Hi Zebidee,

I'm in a Reddit group chat with a couple others and one of them pointed me to your thread. I bought a couple of these Yi Chuang China kit boards from AliExpress back in April 2024, a 14"-21" chassis board for $52 shipped to the US and another 21"-29" board for $61 shipped. I sat on these for a couple years as I didn't have any suitable TVs to put them in. This past spring I found a barely used RF only low end Magnavox TV that uses a floating ground hot chassis. It's common knowledge that these can't be modified without an isolation transformer, and I didn't feel like including one in the enclosure as this thing is heavy enough. It also likely uses digital RGB OSD anyway with no s-video and component capability.

I started working on this project shortly after I found the TV and have a full diary here showing what all I've done over the last 5 months:

https://www.reddit.com/r/crtgaming/comments/1w9e56m/china_kit_aliexpress_board_swap_great_results/

I do have a few questions, but wanted to grab your attention again first. Really glad you're still active on the forum. Are you based in India?

Production Side artwork:

FE Menu background:

I’m trying to find the factory/service-menu entry code for a Memorex Sphere Videoball MSP-TV1300.

Hardware:
MCU: M37272M6-354FP
Jungle: M61266FP
Main PCB: 190-021301-P1
CRT: IRICO 37SX110Y22-DC05

Already tried the common Memorex/Orion, Prima/Advent, and MENU 6483 methods without success.

Does anyone know another TV using the exact M37272M6-354FP, or the service code for this one?

I tried sending you a DM but the system wouldn’t let me maybe cause I’m new here.

Now that your first post is approved, your PM system should be enabled.   


Scott

Hey nipsmg, I tried sending you a DM but the system wouldn’t let me maybe cause I’m new here.

I pulled the skee ball game out of the crawl space and have it all set back up.  I put an arduino on it back in 2014.  Anyway, I’m using python and pygame to create some skee ball games to replace the arduino.  Similar to what you have here but customizable so I can control the beacon light and ball release solenoid.  I have my own classic skee ball version implemented already.  I would like to duplicate some of the games you created.  I didn’t see any licensing information for Major League Skee Ball.  Was wondering if you’d have any issue we me porting some of your games to pygame for my machine.

Thanks!

Hey guys
Sorry for the dumb question

But does anyone know how this machine collapses
I see hinges on the backside
But don’t know how to get it to come down for transport

Thank you very much