Results 1 to 19 of 19

Thread: CRT Screen roll during bright flashes *FIXED*

  1. #1
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28

    CRT Screen roll during bright flashes *FIXED*

    Hi,

    This problem only happens when using the RGB SCART Cable, working fine on composite.

    It happens during quick flashes like in the original Metal Slug and the end of the intro then the logo metal slug appears on screen after the cannon shell hole.

    Here it is recorded on my Setup.
    https://www.youtube.com/watch?v=pmKV0vSUE5E

    My Equipment
    Japanese AES S/N 121894
    Board version 3-5
    PSU : SEGA-CD 1602-1 10v 1.2A

    TV: 32" CRT LG FLATRON

    Video Converter
    Shinybow SB-2840 Scart to Component

    Scart Cable :
    https://www.ebay.ca/itm/Neo-Geo-AES-...53.m2749.l2649

    Do you think my cable has improper capacitor / resistor installed?

    I know that the cable version that I bought is not the best one I guess....

    Do you think getting a better quality shielded version like this is worth a try?
    https://retro-access.com/collections...-scart-tv-lead

    Thanks
    Last edited by Ricard350; 11-13-2017 at 10:58 AM.

  2. #2
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Forgot to ask, is it dangerous for my TV if I continue using that cable? Or should I go back to composite?

  3. #3
    We have purposely
    trained him wrong
    ...as a joke.
    ChuChu Flamingo's Avatar
    Join Date
    Nov 2010
    Location
    US

    Posts
    1,734
    If you're using CSYNC and not composite video as the sync you need to make sure it has the right resistor for proper 75 ohm termination (unless your device is cool with TTL sync then all is well).

    Many people take it lightly, but if you are sending TTL level voltage signals to your Shinybow and CRT you are definitely pushing both past its maximum factory specifications. You are shorting the lifespan of it if so, but by how much is anyones best guess.

    Do you have a multimeter? You can easily test to see what component/pinout is in your cable.

    http://retrorgb.com/csync.html


    Here is a diagram of the pinout.




    I don't think your AES 3-6 has Csync on the output, but composite video on both pins 3 and 7. With this in mind that cable may be using composite video as sync and running it through a lm1881 sync stripper to get CSYNC . In the description he has this

    This cable use an new picture boosting technology to reduce checkerboards problems in the picture
    Kinda sounds like he amplifying the sync signal.


    You really need to check your cable to verify as the output of sync strippers is definitely TTL unless attenuated.
    Last edited by ChuChu Flamingo; 11-01-2017 at 10:18 PM.


    he spends hundreds on scarves, of course he's a fag and then ChuChu Flamingo preserved the aftermath in a plastic case making sure it wasn't exposed to unstable air
    You're just upset that you're too goddam stupid to understand the games and whiff infinites.

  4. #4
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Yes I have a multimeter, what test do you want me to perform?

  5. #5
    We have purposely
    trained him wrong
    ...as a joke.
    ChuChu Flamingo's Avatar
    Join Date
    Nov 2010
    Location
    US

    Posts
    1,734
    Quote Originally Posted by Ricard350 View Post
    Yes I have a multimeter, what test do you want me to perform?



    The first course of action is finding out if you use Pin 3 or 7 for sync. AES versions up to 3-4 have CSYNC on pin 7, composite video on pin 3. 3-5 and 3-6 have composite video on both pin 7 and 3 linked iirc. If im wrong someone please correct me.

    but your cable should just be using Composite Video as sync, not CSYNC if im reading the diagram right. If that is the case you don't need a resistor on the sync line. However if the person took that composite video and ran it through a sync stripper such as a lm1881 or a buffer circuit it should have the proper resistor on the output.


    you could always ask the seller what pin he uses and what he puts in it as well. That retro access one looks pretty good, she makes good cables.

    Best of luck fixing this. I would pm Xian Xi and ask him about this if you're still having troubles.
    Last edited by ChuChu Flamingo; 11-01-2017 at 10:17 PM.


    he spends hundreds on scarves, of course he's a fag and then ChuChu Flamingo preserved the aftermath in a plastic case making sure it wasn't exposed to unstable air
    You're just upset that you're too goddam stupid to understand the games and whiff infinites.

  6. #6
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Will I be looking at the same number/value as the video presented?

  7. #7
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    The only thing that I can say for now is that Pin7 on the round plug is wired to Pin 20 of the SCART end.... pin 3 is "OPEN" to pin 20 of Scart...

  8. #8
    We have purposely
    trained him wrong
    ...as a joke.
    ChuChu Flamingo's Avatar
    Join Date
    Nov 2010
    Location
    US

    Posts
    1,734
    Quote Originally Posted by Ricard350 View Post
    Will I be looking at the same number/value as the video presented?
    It is different for each console as the TTL voltages can vary quite a bit. Your AES shouldn't have CSYNC on the output unless someone did a mod iirc. I would pm Xian Xi and ask him on what may be the cause.

    http://www.neo-geo.com/forums/member.php?12537-Xian-Xi


    he spends hundreds on scarves, of course he's a fag and then ChuChu Flamingo preserved the aftermath in a plastic case making sure it wasn't exposed to unstable air
    You're just upset that you're too goddam stupid to understand the games and whiff infinites.

  9. #9
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Inside the SCART connector there is 3 extra resistor that are on Pin 7,11 and 15 which are the BLUE, GREEN, RED line and all 3 of them go to pin 20.... that seems weird according to this picture...


  10. #10
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    My cable is not even grounded so it basically fail the first test on the video lol din end metal connector to scart connector and its freakin "open"...

  11. #11
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    I test it out on my Panasonic Plasma VT-25 and the screen roll dosent BUT I have noticed distortion on the top signal suggesting Xian Xi that I have read from this post...
    http://www.neo-geo.com/forums/showth...troubleshootin

    Im using the Sega CD 10v 1.2A so its borderline as I read that it could draw power up to 1.5A on bigger game. So my next step is to get a 9-10V psu 2.0A...

    Ill keep you posted as there is probably 5% chance that I find a universal one in my shitty town..... :P

    Worst case scenario how bout this one?
    http://gamedoctorhk.com/index.php?ma...oducts_id=1931

    I think I have found the HOLY GRAIL !
    https://en.retrogamesupply.com/colle...enesis-mega-cd

    Perfect with 3A rating and I have a Genesis with sega cd....

    I am gonna ask if they can provide me another removable DC jack that has just 1 plug for when im gonna use it with the AES as I dont really want to have a loose live dc jacks dangling in the back of the AES....
    Last edited by Ricard350; 11-02-2017 at 10:32 PM. Reason: Extra info added instead of making another post as I'm already spamming the shit out of my own thread...

  12. #12
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Quote Originally Posted by ChuChu Flamingo View Post
    Kinda sounds like he amplifying the sync signal.
    You right as mentioned earlier, I saw the the red, blue and green signal line are also wired to the sync (pin20) thru what appears a resistor.

    Perhaps my TV just dont like that signal that might be amplified specially during the bright flashes...

    I will probably try to order a new cable from retrogamingcables.

    Since my board revision 3-5 only output composite video for sync, do you recommend me to ask for a LM1881 sync cleaner to be also installed on the cable?

    Apart for the screen roll on bright flashes the colors output seemed flawless no checker board or jailbars....

  13. #13
    We have purposely
    trained him wrong
    ...as a joke.
    ChuChu Flamingo's Avatar
    Join Date
    Nov 2010
    Location
    US

    Posts
    1,734
    Keep in mind if you get a fully shielded cable there is no difference between CSYNC (composite sync) and composite video as sync. The reason to go CSYNC is for compatibility reason like some scalers/monitors and recorders need CSYNC.Sometimes certain monitors need TTL voltage to. CRTs usually don't give a shit.

    I almost always go with CSYNC, then Luma as Sync for all my cables. Keep in mind if you use a LM1881 sync stripper it will delay the sync and shift the picture horizontally 5 pixels. Not really a deal breaker, but can be a pain in the ass when you dial in the geometry and then the picture is shifted on just that console. Just make sure whenever you get a CSYNC cable that it is properly attenuated as CSYNC is almost always TTL voltage and not 75 ohms.

    Both major cable manufacturers (Retro Console Accessories and Retro Console Cables) should be putting in the current resistor to bring TTL CSYNC to 75 ohms for whatever console you buy. It never hurts to look up the pinout of whatever cable you buy though and check yourself with a multimeter if a resistor is on the sync line. Just keep in mind those two sellers put it in the console side connector which means you won't see it.
    Last edited by ChuChu Flamingo; 11-06-2017 at 07:25 AM.


    he spends hundreds on scarves, of course he's a fag and then ChuChu Flamingo preserved the aftermath in a plastic case making sure it wasn't exposed to unstable air
    You're just upset that you're too goddam stupid to understand the games and whiff infinites.

  14. #14
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Quote Originally Posted by ChuChu Flamingo View Post
    The reason to go CSYNC is for compatibility reason like some scalers/monitors and recorders need CSYNC.Sometimes certain monitors need TTL voltage to. CRTs usually don't give a shit.
    Yeah I think I am only gonna go with a standard cable without the sync stripper like you said. It looks like I was going a bit OVERKILL.

    Ill order a new cable and keep you guys updated...

  15. #15
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    Just for an update
    Here what it looks like my SCART connector...



    Very weird hack job huh?

    Notice anything out of the ordinary, like those 3 yellow wires??? Anybody ever seen Red, Blue and Green lines all wired to the Sync pin 20? Each line has also a 260ohm thru them. This is what the yellow wires are...

    The vendor said that in the description of the Cable : This cable use an new picture boosting technology to reduce checkerboards problems....

    Perhaps this is some sort of means to amplify the Sync signal?

    I think this is what my CRT dont like, hence the Screen Roll.

    Think I am gonna try to cut those 3 yellow wires....

  16. #16
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    I have cut the 3 wires, and no diffrence, still screen roll during bright flashes, but apparently his hack job of "This cable use an new picture boosting technology to reduce checkerboards problems in the picture" worked because now i have a slight checkerboard on the blue snk logo during boot screen, I did not had it before ....

    I guess my CRT is just finicky perhaps because of the neo geo 61.18hz refresh rate.... or maybe my scart video converter, but this one works flawlessly with my Genesis model2 ....
    Last edited by Ricard350; 11-09-2017 at 01:07 PM.

  17. #17
    We have purposely
    trained him wrong
    ...as a joke.
    ChuChu Flamingo's Avatar
    Join Date
    Nov 2010
    Location
    US

    Posts
    1,734
    I still think you need to buy a properly built cable. Just because you removed those rgb lines being connected together the sync is still being boosted,not wired correctly.

    It seems you lose picture whenever something extremely bright shows up, which points to sync voltage being too high as a white screen pushes out more voltage.

    Also dat glue, Drakon would be proud.


    he spends hundreds on scarves, of course he's a fag and then ChuChu Flamingo preserved the aftermath in a plastic case making sure it wasn't exposed to unstable air
    You're just upset that you're too goddam stupid to understand the games and whiff infinites.

  18. #18
    New Challenger
    Ricard350's Avatar
    Join Date
    Oct 2017
    Location
    Cold Lake, Alberta

    Posts
    28
    My friend just gave to me for free a Sony Trinitron 32" KV-32FS120 and it works FLAWLESSLY! I also heard it hit or miss for CRT as the AES non standard 61.18hz refresh rate it could have been that my LG did not liked it...

    This is how I feel right now...


  19. #19
    Timid Neo Newbie

    Join Date
    Jun 2016
    Location
    greece

    Posts
    5
    My LG LED Tv also don't like non standard refresh rates for example n64rgb pal console with ntsc roms using ossc.....

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •