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Everything posted by Taijigamer

  1. Nice work. Looking forward to seeing your final design. I completely forgot about TTL sync voltages. Definitely need to add a 330-470 Ohm resistor in series to the csync line output. If not then the 3.3v decoder in the video display will get eventually damaged from the 5V sync. The only reason to have a switch to keep TTL levels would be for VGA displays. Did u manage to test RGBHV on a vga display? I know what u mean about 0402 packages. Ugh! Never again. I stick with 0603 for chip resistors and chip caps. I use 1206 for led and 1206/1411 for tantalum caps. I will try to put together a tutorial for installing RGB on the BT9101 and BT9103 encoders when I've finished testing. Looks like blanking isn't required for newer TVs. May still be required for older CRTs.
  2. It depends on the quality of the upscaler in the tv. RGB is sharper and more vibrant than Y/C but it will still be at 240p/480i. I will be installing my new RGB mod as soon as the parts arrive so I will be able to get a better idea after that. I've got an older SD crt and a newer HD LED so I will be able to get a good comparison. I will let u know :-) As I said, for retro consoles, I recommend RGB + XRGB/ OSSC on a HD tv or RGB + CRT/ BVM monitor. Edit: also check out this thread for discussion on 3DO + Tv type http://atariage.com/forums/topic/153978-3do-lcd-or-tube/
  3. I've been there myself. I managed to get the rows mixed up on a xbox360 DVD power adapter I designed for flashing Xbox DVD drives. Had to reverse the wires on the power cable to compensate. If the SMD lands on your pcb are suitable for 2 of the SOT-23 diode leads then u should be able to get away with it for this batch of test boards as the 3rd pin is NC like you said. It's all part of the R&D journey This design will work with all 3DO as it takes 24bit RGB from the board and strips SYNC from Luma. It bypasses the native encoder. The pinout for the other encoders can be found in this thread https://assemblergames.com/threads/240p-output-on-3do-with-bt9103-encoder.66295/
  4. Full credit goes to @The_Crayon_King for this one. I've just chimed in with a few observations. Quick work on the design change, very nice. These will definitely work, it's just a matter of testing now. With all the research so far, these should work across all 3DO and also some Philips CDi models. The good thing about the ADV7125 is it's high end so it will give stable standardised RGB outputs. Just stick to the recommended Vset and Rset values. With the BU3616K, there is not a lot of info in the data sheet and Rset was valued too high which was evident in the reports by other modders who found the picture very dark. I've had to work out Rset from what little information was given. Regarding 5V, I recommend getting it from an analogue 5V source close to or from the VA536. The 7805 is a digital source and will be 'dirtier' than the very clean analogue 5V that the VA536 will use. If you want someone to test your design on the BT9103 encoder then let me know, I would be more then happy.
  5. The board looks like his own idea. It uses a BU3616K chip which is popular amongst modders for doing their own 3DO RGB mods. It's cheap and simple. Not sure why he extended the board out from under the CD rom, he could have kept the chip directly over the original encoder and saved pcb space. This design is great for VA536 encoders as it piggy backs onto the chip.
  6. Thank you for your comments. I realised I had placed C5 and C6 were too close to the IC, if I keep them in the final design, I will move them to a better position. They are extra power decoupling caps so they may not be needed. If I do move the filter caps and resistors back to the pcb, I will use your design as it's the best layout. That's interesting using the MD-80SV. I was going to use a C shape 8 pin din panel mount as these are the easiest to acquire. The only issue was finding good quality SCART cables with a 8 pin din connector for a good price. I plan to release my design as open source for people to use as an alternative to the old DAC ladder design. I would of course give credit to your design as it has been very informative and helpful in my own research. I originally reviewed 6 different 8bit triple dacs and found the ADV7125 and BU3616K to be the best choices, with the ADV7125 being more high end. I have potentially deciphered the other 3DO encoders so your design should be fine to work across all 3DO https://assemblergames.com/threads/240p-output-on-3do-with-bt9103-encoder.66295/ I look forward to seeing how well your design works. :-)
  7. Looks good. Here's my BU3616K design I have left out the 75Ohm + 220uf from the circuit to keep it smaller and cheaper. I was going to put them in the SCART socket but I may add them back to the pcb after seeing your design. I have also wired CLK and SYNC away from the RGB to avoid interference. I have kept the LM1881 circuit simple with just a 0.1uf cap and 75 Ohm termination resistor on Sync in. The LM1881 circuit that you have used is the full circuit but I haven't heard of any sync issues so I have kept it smaller and cheaper. This is just a proto design and I will probably modify it after testing and troubleshooting.
  8. The VA536 produces its own Blank signal but the other 3DO encoders get it from the CLIO chip. My theory was that as long as the pinout of the CLIO was unchanged and the Blank signal was still produced (though not required), you could wire Blank from the CLIO. But it looks like you have solved that problem anyway :-) I had the same thought About HV sync with my design. I've kept pins for both CSYNC and Vsync so I could test VGA compatibility. But I think most modern PC monitors only accept 480p signals and above. Older monitors accept 240p I think. I had to edit Eagle foot prints as the BU3616k wasn't listed. Assigning all 48 pins was a ball ache. Good luck with your prototype, very interested to see how it turns out.
  9. Glad you are making progress with this :-) Yeah I'm not sure about Blank either. Like you said, the timing could be off by using the Back Porch signal. I've noticed that the BT9101 and BT9103 both use Blank signal. I will try and trace my BT903 Blank pin to the CLIO chip. Hopefully the same pin on VA536 motherboards will provide an active Blank signal. Do you have a picture of the RGB mod chip you found? It sounds like they might have used a BU3616K chip which is about the same size as the ADV1725 but simpler in design and application.
  10. All 3DO are RGB able. The video encoders in the 3DO are unable to output RGB so another circuit is added to convert the 24bit digital RGB to analogue RGB. The old method used 3 DAC chips and another IC to produce a sync signal. Because of this the board was quite big. It would be interesting to know what this French shop is using, whether it's just another Otaku board or a newer smaller IC. The problem is whatever the circuit, it will always require soldering 24 digital RGB wires to the motherboard so people without experience will need to rely on modders and shops to install RGB on their 3DO.
  11. It's the TV. Modern LCD/LED TVs have bad results with 240p/480i video feeds. They are designed to display 720/1080p so they have to upscale lower resolutions. The upscalers in the TVs aren't great at this. That is why people invest a lot of money in upscalers like the XRGB/ frameister or OSSC. On a CRT, the difference is more noticeable between Composite and S-video. The best option for picture on a HD TVs is RGB --> upscalers (XRGB/ OSSC).
  12. Glad you have got a working console. I know what u mean, sometimes it's nice to take a break from fixing things and just play. Let us know if you do manage to fix the other one. Happy gaming.
  13. Hmm. Maybe the laser is actually on its way out after all. I would have also checked a Japanese specific game before removing the ROM2 to confirm it being the Kanji chip. Keep that ROM safe incase u do want to play jananese only games in the future. Edit: Fantastic! Glad it's finally working. Wonder why that game worked but the others failed?
  14. Thanks. That's very interesting. Your FZ-1 motherboard has 2 ROM chips. ROM 1 is the Bios (IC341) and ROM 2 (IC340) is usually blank on US and PAL consoles as it's usually where the Kanji chip goes for the Japanese games which have Kanji fonts. Which games did u test on the console? Some US games wouldn't play on a Japanese consoles with the Kanji chip. http://3do.cdinteractive.co.uk/viewtopic.php?f=25&t=3739 This thread shows how a guy was able to remove the Kanji bios to allow the console to boot US games. Possibly something to look at in the future if u want to get this console booting games again.
  15. That's a good find. Just swap the CD drives and you should be good to go. If u get a chance, could u post a picture of the Bios chip? It would be interesting to see if it's a different IC to the stock IC or just flashed with a custom Bios Rom.
  16. That's great that u solved it. do u know which game it's programmed to work with? Can u post a picture of the bios chip? This may explain why other people get this issue rather than the asteroid screen. I've read about people swapping bios and adding kanji bios, maybe this can be done with your motherboard to give u full access to the games library. Glad u got it figured out.
  17. The flashing access light and and sled behaviour is classic for a laser struggling to read the disc. I haven't seen that flickering behaviour before. I would try to adjust the pot to try and get the laser to read the disc. What was the base resistance before u adjusted the pot? I would look into replacing the laser. Replacements are hard to find as there is no direct drop in replacement. The SF-92.5 is the nearest replacement but requires modding to work in the Panasonic 3DO. There were some direct drop in replacements available on AliExpress a few years back but I've had no response from the seller regarding restock. I'm looking into easy reliable solutions with the SF-92.5 but it could take time as I'm also in the middle of designing RGB mods for the 3DO.
  18. Panasonic_FZ-1_Power_Supply_30W.pdf Here is the power supply schematic for the FZ-1
  19. I've been meaning to open up my 3DO and get some values from the FZ-1 CD drive but life has been slowing me down recently. I'm not sure of the voltage supplied to the laser but its the current that's important. This post from 3doplanet explains measuring the current supplied to the FZ-10 CD drive http://forum.3doplanet.ru/viewtopic.php?f=17&t=701. By measuring the voltage across R720 (FZ-10) we can workout the current supplied. According to the thread, 50-100mA is the norm for a healthy laser. I'm not sure what the equivalent resistor is on the FZ-1 but I will try to look when I next get a chance. The other option is to adjust the laser pot on the laser head. This isn't the best method but it may be a quick way to see if the problem is a failing laser. There is no set resistance that lasers come with as they are all calibrated slightly differently. Just take a baseline resistance reading of the pot with a multimeter and then reduce the resistance by 50 Ohm at a time, testing in between. Hopefully the laser should manage to read the disc. Just make sure u are testing with a retail disc with minimal scratches. I was going to recommend this video but I see u have already asked GadgetUK about the laser problem. He brings up good points, did u change the CD drive caps when u recapped? As for the service manual, I'm currently following a few leads and hopefully may be able to get hold of a copy. I'll post a link if/when successful.
  20. I'm working on a RGB board using the BU3616K encoder. It's been done before by modders here and in Japan with success. Once I've finished designing and testing, I'll put out a post to gauge interest. I don't think Otakus store are producing any at the moment which has pushed me to develop and updated version. There is another member looking at the ADV7125 encoder as another solution http://atariage.com/forums/topic/260654-new-3do-rgb-mod-possibility/?do=findComment&comment=3808787
  21. Are u still getting the 3DO logo at the start before black screen? I have a theory with this 3DO problem. The CD drive must be included somehow with the 3DO start up. When I remove my cd drive and try to boot the console, it behaves the same as yours. Either a malfunctioning cd drive logic board or a bad laser head could be the culprit. The way to test would be to get another known working panasonic 3do cd drive and attach it to see if the console boots. If you don't have access to another Panasonic 3do then attempting to replace the laser head could be your next option. If u have an oscilloscope, u could also make sure your psu is delivering stable voltages. A cap replacement won't always solve this as your voltage regulators etc could be faulty. I would look at the laser first though.
  22. What currency are referring too? $130 - $150 seems like the common price at the moment. Depends on what they come with, games, controllers etc. Even faulty ones sell for $60. Then u need to be aware of importing models from other regions which may need a step down/up converter which will add to the price. It's a shame they cost so much but retro consoles have grown in price. I managed to get my FZ-1 for $60 as faulty but was easy to repair. I would shop around, hopefully a cheaper Panasonic 3DO will become available. I've heard that Golstar and Sanyo 3DO aren't as good as Panasonic.
  23. Thanks for the link. His instructions refer to the Goldstar 3DO but the principals are the same. Here is the wiki link for the Panasonic FZ-1 caps and ICs. https://console5.com/wiki/Panasonic_3DO_FZ-1 I haven't read about problems with the CD drive caps but it's worth a look. The more likely issue with the CD drives is Laser heads. These are SF-92.5 laser heads. They can be found easily enough but some may require modification to work in the CR-563 type drive.
  24. Sounds like a good plan. Check this site for cap kits. https://console5.com/store/panasonic-3do-fz-1-cap-kit.html It also has a wiki with cap list, ic list and values for reference.
  25. Hi, how's it going. I have seen this behaviour in some Panasonic 3DO where it will not boot to Bios screen. My Fz-1 does it when I remove the cd drive ribbon cables. This leads me to believe it might be a dead laser issue. Something is probably happening in the communication between the cd drive and the CPU which is sketching it out. Your psu and video encoder are working fine because u get the 3DO logo at the start of boot. The other reason could be the bios chip isn't getting the correct power which leans towards re- cap. The system is almost 25 years old sons laser replacement and re-cap is inevitable. The price we pay for maintaining antique hardware. Lasers are hard to come by. U will need an SF92.5 but they sometimes need modification.
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