Best way to get Japanese Saturn working well on an HDTV?

Discussion in 'General Sega Discussion' started by MarzSyndrome, Aug 9, 2013.

  1. Meat Miracle

    Meat Miracle

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    NTSC and PAL are both colour encodings. If you use RGB, you can get proper colour on any TV that supports it, since it does not encode colours, it just sends the R, G, B channels directly.

    As for the cut-off parts, where does that happen? I'm asking because if you run a PAL optimized Saturn game in 60hz, it will have the bottom of the screen cut off.
     
  2. doc eggfan

    doc eggfan

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    I haven't really read (or understood) anything in this thread, but I just bought my Japanese Saturn home and it works with my dvdo iscan pro v2 line doubler. Gets me reasonably decent 480p on my flat screen.
     
  3. MarzSyndrome

    MarzSyndrome

    Everything is going to the beat. Member
    I took part of your advice in my mind yesterday, and decided to fork out for one of these:

    http://www.ebay.co.uk/itm/170979823127?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

    Hopefully that's exactly the sort of thing I'm after, right?

    EDIT: Wait, reading up a bit more, I may need a converter cable as well, yes? Like this one for instance?

    http://www.retrogamingcables.co.uk/european-scart-to-japanese-scart-converter.html
     
  4. Meat Miracle

    Meat Miracle

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    Those Scart cables oughta work, yes. However since they are third party, I cannot tell you how the quality will look - if they are not properly shielded cables, they might have so much interference that you are better off with composite.

    RGB21 -> Scart converter is only needed for the official Sega branded RGB21 cable. RGB21 is like Scart but uses a different pinout. I'm leaning to think that the cable you linked to on ebay is Scart, not RGB21. But the signal output is the same so even if it IS RGB21, you can just open up the cable and rearrange the pins.
     
  5. Shadow Hog

    Shadow Hog

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    People I know who are hellbent on getting the best quality video out of their old gaming consoles swear by the SCART cables from retro_console_accessories on eBay, I find. She also says she can wire them up for JP21 at no additional charge.
     
  6. Mentski

    Mentski

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    Is there any reason you can't jump pin 8 to 16 (with a 100ohm resistor in between) in the SCART plug to trigger RGB mode instead of having to open up the Saturn and rewire a pin?

    That's how Mega Drive RGB cables (and other consoles that don't have a dedicated voltage coming out of them for this type of thing) works.

    Obviously disconnect the wire already coming from the Saturn to pin 16, because it's CSync, not voltage. In fact, if you wired that to pin 20 of the SCART instead of the comp video wire already attached to it, depending on your TV there's a chance you might get a better picture too.

    (SCART Standard uses comp video to sync an RGB signal, but most TVs will take a raw sync signal from the pin instead if it's coming from the console with enough "oomph")
     
  7. Meat Miracle

    Meat Miracle

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    Because there is a difference in the a/v port between PAL and NTSC Saturns. NTSC Saturns output c-sync on the pin where PAL Saturns output +9/12v. The official SCART cables released in Europe are mapped to use that pin, so they only work on PAL consoles properly - on NTSC machines, they have c-sync connected to the RGB select pin, which is unstable at best.
     
  8. Mentski

    Mentski

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    Er... Yes. I understand that. I don't think you quite get my gist.

    I'm saying instead of opening up a JP Saturn and rewiring the AV port so it outputs voltage instead of csync to make the PAL cable work, you can get a voltage line to trigger the RGB switch straight from the TV by jumping pin 16 (RGB Select) to pin 8 on the SCART end (with a 100ohm resistor in between).

    That also gives you the bonus of still having a dedicated csync coming out of the Saturn that you can then use to sync the RGB signal instead of composite video, by connecting the wire previously connected to pin 16 (which would be the line supplying voltage out of a PAL Saturn, but out of a JP saturn, as you rightly say, is csync) to pin 20 in the SCART plug.

    Do you see? That (should) make a PAL Saturn cable usable on a JP Saturn without any rewiring on the Saturn end, and keeps the valuable cysnc signal, which is better for syncing an RGB signal on many modern TVs and scalers.

    (In fact, I'd bet my left bollock that that's EXACTLY how the 3rd party JP Saturn - SCART cables you get on Ebay are wired up)
     
  9. Meat Miracle

    Meat Miracle

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    Pin 8 & 16 are already joined on the Saturn SCART cable; both are fed from the 9v pin, with a resistor inbetween the two pins. They are input only pins, there is no outgoing signal from the TV in them.

    The Megadrive outputs +5v and the RGB cables I have for it use that for RGB switching. They don't autoswitch to the video channel though, you need over 9v for that. PAL Saturns with the scart cables all auto switch to the channel.
     
  10. dsrb

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    Devil's advocate here!

    I bought two cables from this seller, hoping it would fix my aforementioned problems with my aforementioned NTSC-J Saturn. Both provided pictures with huge distorted bands emanating from any hard-edged shapes and other problems. This occurred on various TVs. I tried both cables on my PAL Saturn into multiple TVs and got all the same problems

    I eventually got a refund, but not without retro_console_accessories basically telling me that had never happened to anyone else and so I must be doing something wrong.

    Considering how I controlled my tests with two cables, two Saturns, two regions, and at least three TVs, I find it hard to believe all of those things of mine had the same problem(s), whereas their cables were innocent.

    Of course, any enlightenment that might explain the whole thing - and make me look like a silly ass - would be welcomed, but at least for now, I thought it was worth recording that not everyone has had a flawless experience with their products.
     
  11. Mentski

    Mentski

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    Hmm. I just had to add a sync stripper to the comp video line on the SCART end of a couple of MD cables I had to prevent jailbar effects, I swear blind the RGB pin wasn't connected to anything from the MD.

    I've only just bought A 32X raw sync cable from them that they claim work on EU Samsung LCDs (The raw sync cables I made worked on my Sony but not on the Sammy) I dearly hope they do live up to their rep and it's not all bullshit.

    (Having said that after what Meat Miracle has just said to me, I'm starting to wonder if the reason they're not working on the Samsung is because the RGB select pin isn't getting voltage from the MD. Ho hum)
     
  12. Meat Miracle

    Meat Miracle

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    I use Retro Computer Shack RGB scart cables fro my md1 and 2, and they are well made enough that I have only minor audio noise and jailbars are limited to what the system outputs (I have modded my system to reduce it). No sync stripper. I think they use composite video for sync, not sure, I'd have to re-check.

    I do have this long standing problem with the video jumping from center to left-bottom, I think the output filters need to be recapped, as it happens on any rgb cables I tried so far.
     
  13. dsrb

    dsrb

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    I've bought an RGB SCART cable, main PSU, and spare disk drive PSU for my Amstrad CPC 464 and 6128 from Retro Computer Shack. All worked fine, aside from the fact that some TVs simply disagree with that type of signal.

    To be clear, I'm not wanting to slander retro_console_accessories, but I can't fathom how the problem could have been caused by me and not their cables. As I said above, if anyone wants to school me and vindicate r_c_a, feel free.
     
  14. MarzSyndrome

    MarzSyndrome

    Everything is going to the beat. Member
    Welp. That RGB SCART cable I bought and acquired a day or two ago has proven to be no different than all the other SCART cables in my possession. Already asking for a refund.

    If there's an easy dummies guide to modding a cable or the Saturn to make it not do monochrome or 'spasming' video on 50Hz displays then by all means let me know about it. (But first I'll really need to know how one opens up a SCART plug to check the wires and then put it back together again so that it isn't a lost cause.)

    Otherwise I'll have to consider the more expensive option of buying that XRGB mini (and an adapter plug to go with it) and output my Saturn (and possibly all other consoles) through that instead - especially if it'll also allow me to reduce overscan and generally have full control over horiztonal and vertical sizing and positions.
     
  15. Meat Miracle

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    To get 50hz colour in composite/s-vide out for a NTSC Saturn, you have to change the master clock (or install a secondary clock for the video board).

    You are better off buying a PAL machine with a 50/60 switch and either a region free bios or a modchip, depending on whether you want to run originals or copies.
     
  16. MarzSyndrome

    MarzSyndrome

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    And where is such a guide for changing the master clock anyhow?

    :( I specifically got a Jap Saturn to make a change after being stuck with a not-100% chipped PAL Saturn for years before. I don't really fancy having two Saturns in future! XRGB it is, I guess.
     
  17. Meat Miracle

    Meat Miracle

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    ... what do you mean not-100% chipped Saturn?

    To change the master clock, remove the 14.318 MHz crystal oscillator marked as X1 on the board, replace it with a 17.7344 MHz one (not sure about the exact MHz but it should be PAL colorburst x4), and change around the JP1/2 jumpers. This effectively turns your machine into a PAL unit in everything but region settings.

    Or, you know, hack off the a/v end of one of your third-party scart cables, and solder your own cable that uses the +5v line to lock onto RGB signal. In fact, I'm not sure the xrgb needs the RGB selection voltage, if it does you'll be none better off (other than owning a hardcore upscaler).
     
  18. MarzSyndrome

    MarzSyndrome

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    Well okay, more like a "non-CDR-capable" Saturn. It could read original imports through the region switch, but nothing burnt.
     
  19. Meat Miracle

    Meat Miracle

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    If you are okay with burning regionmodded cdrs or using an action replay, I can sell you a chipped + 50/60 switch equipped PAL Saturn for 105£.

    Not sure if I could include a region switch too, it would at the very least need a hole cut in the case, and I don't know if I have any spare multi-state switches.
     
  20. Shadow Hog

    Shadow Hog

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    Dunno. I'm only just coming across this post today, coincidentally the same day I come across this post on NeoGAF:

    So, well, she's not flawless.

    Glad I'm hearing about all of this before I start going RGB crazy, though.