Taijigamer

Learning to solder well is definitely recommended, especially as our beloved consoles are getting older and more prone to failure. But be sure to practice on junk circuit boards until competent. The SRAM upgrade idea isn't simple and may not work. A plug in option would be easier. Maybe the memory addon module could be cloned if someone opened one up and documented the insides.

I've been looking into the storage on the 3DO. The on board storage is a paltry 32kB. The memory addon pack cited above is 256kB. I have found some 128kB and 512kB 5V SRAM chip datasheets which could probably be swapped in (with a bit of adjusting) and give a boost in memory capacity. I'll test when I get a chance.

The battery on the 3DO maintains the on-board SRAM chip which holds the limited save space for games. I think an NVRAM add-on could be purchased to increase space. To swap the battery without losing saved games, u would need to supply an external 3V to the chip while u desolder and replace the existing battery.

Save data is stored on the on board SRAM (not sure of capacity). This is maintained by the battery when powered off. I think there is an external NVRAM add-on block that could be purchased to increased save storage. I saw one on eBay a while back.

Great work. I'm not sure how hot my FZ-1 gets but the voltage regulator heat plate is big and the area still gets very hot which is why the power caps have a high failure rate. I'll check the temp of my regulators with my k-probe when I get a chance. I would recommend a cap replacement if you want to extend the life of your console. Console5 do quality cap kits (105c rated). As for RGB mods, there are a couple around. I'm working on a RGB_V2 which should be finished soon.

I've seen that mod board before. I think it's some sort of SECAM conversion as old French Tv don't accept Composite. Have you got closer pics of the motherboard? What video encoder does it use?

Yes I saw that typo. Datasheet rates it as 16V CT (centre tapped). It will still be AC voltage until it exits the bridge rectifier. Attach everything as normal. Good luck with the install. Any questions, feel free to post or PM me.

Nice find, I didn't see that one. In regards to VA, it depends on the power factor of the psu. Unless the power factor is 1, you will want some VA overhead. Maybe 35-45VA to be safe. As for output, don't worry too much about getting exactly 15VAC, that was just a DMM reading. The voltage regulators will accept 10-30V. I measured the transformer in my 3DO, the transformer u linked has the right dimensions. The one I linked is too tall by 1" :-( Just a shame about the VA. 30 VA might be enough.

Sounds about right. The FZ-1 PSU is integrated into the main PCB and is fairly generic. The only main difference is the transformer (and a common ground connection in NTSC models). Some models have fans and some don't, the connections are still there to add a fan. I have a PAL FZ-1 which has a 230V transformer and outputs ~16VAC. This is fed to a bridge rectifier and corresponding 9V and 5V regulators which can between 10V and 30V. The service manual shows an expected 20VP-P on the transformer output but my DMM only shows 16VAC. This transformer looks like a possible candidate https://eu.mouser.com/ProductDetail/Triad-Magnetics/VPS20-2200?qs=1a1zv8L%252Bh%2F2tr%252BOTTBfGVQ== Just be sure to research as much as possible on power supply electronics, this is mains voltages and things can easily get toasty with wrong application. Panasonic_FZ-1(Service_Manual).pdf

As a general rule of thumb, Early US FZ-1 - BT9101 (RGB - Yes, 240p - No) Late US FZ-1 - VP536 (RGB, 240p - Yes) PAL/ CAN FZ-1 - BT9103 (RGB, 240p - Yes) JAP - FZ-1 - VP536 (RGB, 240p - Yes) Early FZ-10 - VP536 Late FZ-10 - ANVIL (RGB - No, 240p - No) Goldstar GDO-101 - VP536 Goldstar GDO-202 - ANVIL Goldstar GDO-203 - ANVIL Sanyo Try - VP536 Not sure about serial numbers, it might be a good idea to get a database of serial numbers going so we can get an idea of what's in what.

It depends on the video encoder on board. You will have to open it to check. BT9101 cannot be modded for 240p but can still be modded for RGB. BT9103 and VP536 can be modded for both 240p and RGB. I am working on an encoder replacement mod for BT9101 3DO so that they can handle 240p but it's not a simple mod.

You could remove the rf box and cut a hole in the case there using the emf shielding cut outs as a guide. Then use a 8 pin din for RGB out. You would need to wire a switch for the 240p to replace the native switch but it would retain the aesthetics of the RGB mod.

Thanks for the info. Looks good. I will add that one to the list of 3DO horror games to play.

Could still be an issue with your laser. Adjusting the resistance pot without the correct tools is only a temporary solution. Chances are that u need a new laser. Also check the heat sink paste and replace if needed.

What model 3DO do you have which is RGB modded? The RGB mod and 240p mod can be done on a few models of 3DO.

VGA would still need RGB analogue conversion which may still suffer horizontal shift on some monitors. I tried to get VGA on my computer monitor but it couldn't display 240p :-( HDMI would be good but u would need to program the FPGA to upscale to 480p minimum and add a pixel clock to facilitate the increased resolution(s). Creating a menu overlay screen would be cool, like UltraHDMI N64, to select different functions. This guy has successfully converted MVS to HDMI and documents the individual challenges https://github.com/charcole/NeoGeoHDMI/blob/master/Notes.md

The good thing about Colecovision is they used standard IC (no proprietary part afaik). So as long as the pcb is free from corrosion and bad traces, u can always repair/ restore it. Some people have actually removed all IC and replaced with sockets to allow easy replacement of dead IC in future. Part of the fun is coming up with solutions to their poor design choices.

Sounds like the laser is getting weak. Consider replacing it. Sanyo 92.5f lasers used in German car stereos are apparently suitable replacements. U want the short lead ones. The long lead ones are incompatible apparently. The other option is to tweak the laser pot.

Picture of the motherboard would be useful to assess the level of cleaning/ repair needed.

Have u replaced all electrolytic caps on the psu? Maybe the laser is faulty and causing a short. Try a new laser. If u still get issues, maybe another component on the psu (5V, 9V regulator?). Check the board for any oxidisation between pins, dry joints.

Use this page from the service manual for tips http://www.colecovisionzone.com/photos/coleco/colecovision%20tech4.pdf. Check for activity from the VRAM pins on the TMS9928 (U9). Most likely VRAM as you said or a bad 9928.

I agree. I don't worry about Wii or GameCube games as they are still readily available through various sources. Nes, Snes and N64 carts are not as abundant and the retro revival has put prices up. I like to maintain original hardware and play on original platforms so the new minis don't interest me. My issue is with the overall attitude of Nintendo, not with EP flaking out. They like to assert dominance regardless of whether it affects their profits. They regularly attack home brew projects even if they are based on games over 20 years old. It's pointless attacking rom sites as there will always be a way to find roms.

Nintendo products.

Sad times. Emuparadise should have made a point of removing only Nintendo Roms. Why should the community suffer completely for their draconian decision making. Nintendofail. Time to boycott.

That's an impressive selection of video games consoles. It's great to see that u have become more familiar with the various video signal and video connector standards. I'm obviously going to reiterate the caution previously mentioned about modding a CRT Tv for RGBS. This should only be undertaken by an experienced CRT Tv technician. This is more for other readers of this thread as u have already stated your intentions. As I'm sure u are starting to realise, it's not so much the connector but the video standard that it transmits. As you are already going to the trouble to install a new video receiving connector, u could use any connector to your choosing rather than a clunky 21 pin SCART. For example, a 8 pin din, 9 pin d-sub etc. Of course using a 21 pin SCART would save u the trouble of rolling your own cables. Most of your consoles already output RGBS. The others can be modded to do so. The ones that already output YPrPb, I would stick with that as it can output up to 480p/ 720p whereas RGBS maxes out at 240p/ 480i (I avoid interlace where possible.) Despite some opinions, using Component (either YPrPb or RGBS) is preferable as there is less chance of colour bleed and blurred edges in the output picture compared to S-video or CVBS.