Menu

Jitter Master System and Mega Drive

Home Forums OSSC OSSC – Discussion and support Jitter Master System and Mega Drive

This topic contains 19 replies, has 6 voices, and was last updated by  BuckoA51 2 weeks, 3 days ago.

Viewing 15 posts - 1 through 15 (of 20 total)
  • Author
    Posts
  • #16672

    wumbo64
    Participant

    I have and issue with a Mega Drive 1 and master system 1, the jitters up and down its really bad and makes the games unplayable.
    I am using Retrogamecables scart leads for both consoles.
    I’ve tried direct connection and through a switcher both with the same outcome.
    I have also fiddled with settings but nothing seems to help.

    On the front of the OSSC it says RGBS 313P 15.55KHz 49.69Hz (with a green sync light)

    Also i am running lots of other systems with out a problem (PAL and NTSC N64s/SNES, PS2, XBOX, Gamecube)

    Any suggestions would be greatly appreciated!!

    #16676

    megari
    Participant

    Have you already tried the settings here? This should help at least in the case of games using interlaced modes. OTOH, I see your mode seems to be 313p, which is progressive.

    Are your Mega Drive and Master System unmodded systems? What games do the jitters occur with? Can you perhaps provide a Youtube video of what you’re seeing?

    #16685

    wumbo64
    Participant

    Jitter video

    They are both unmodified, i have only tried it with Alex Kidd (built into master system) and sonic 2.
    They do the exact same thing as you can see in the video.
    I have messed around with the LPF but nothing appeared to make a difference

    I am using the cables that have a sync stripper built in, Do you think this may be the issue?

    Thank for the quick reply

    • This reply was modified 3 weeks ago by  wumbo64.
    #16690

    megari
    Participant

    Hmm, that might be normal. At least Sonic 2 uses an interlaced mode. Interlaced content deinterlaced using OSSC’s fast deinterlacer has a kind of a jittery effect. Have you tried setting the “480i/576i proc” setting to Passthru? This would use the deinterlacer in your display, which may give a better picture at the cost of higher latency.

    Have you already set the H-PLL coast options as directed in the link in my previous message?

    #16715

    BuckoA51
    Keymaster

    Hmm, that might be normal.

    Definitely not for Alex Kidd like that.

    I am using the cables that have a sync stripper built in, Do you think this may be the issue?

    Seems possible, where did you get these cables from?

    #16720

    megari
    Participant

    Definitely not for Alex Kidd like that.

    Hmm. Does Alex Kidd use a progressive video mode? If that is the case, the jitter is definitely not normal.

    @wumbo64, what does the LCD on the OSSC say when you play Alex Kidd? What is the voltage level of the sync signal when using your cables? If it’s 5V TTL, then you should modify your cables to lower the voltage level to avoid wear on the components of the OSSC.

    #16739

    wumbo64
    Participant

    The cables are from retrogamecables, i believe they are the ones with the sync stripper in.

    The lcd read out for alex kidd is in my original post.

    I will try a couple of the other settings later today

    #16741

    Harrumph
    Participant

    Get new cables, sync stripper is not needed for OSSC and does not improve the signal quality anyway.

    #16747

    Galdelico
    Participant

    @harrumph – I was gonna buy a new C-Sync RGB cable for my Japanese MD2 (mainly to see if it will alleviate the jailbar issues I always experienced with my system) from Retrogamingcables.uk, as they seem to have upped their game and overall improved their products (according to the retro community feedback at least). They don’t seem to mention sync strippers anymore, and they specifically state their new RGB cables are ‘OSSC compatible’. Should I look somewhere else anyway, or am I going to be safe?

    @megari – Where do I read that voltage information on the OSSC? I tried to explore the info menu, as well the sync one, but with no luck.

    Thanks guys. ^_-

    #16748

    paulb_nl
    Participant

    @wumbo64 Can you open up the SCART plug and share pictures of the inside? There should be a resistor on the output of the sync stripper.

    #16750

    wumbo64
    Participant

    i can open one up this evening and get the info.
    So you think new cables without a sync stripper is worth a shot?

    #16762

    wumbo64
    Participant

    Here are the pictures,
    Scart1
    Scart 2

    • This reply was modified 2 weeks, 5 days ago by  wumbo64.
    • This reply was modified 2 weeks, 5 days ago by  wumbo64.
    #16768

    megari
    Participant

    Hmm, there seems to be a 470 ohm resistor (appropriate for dropping the voltage from TTL level) and a 220 µF capacitor in series with the sync line. I don’t see a sync stripper. Maybe the stripper has been moved inside the connector at the console end?

    What console and what version (PAL/NTSC?) did you use the pictured SCART lead on? Maybe someone more knowledgeable than me can comment on whether the 220 µF capacitor on the sync line is appropriate for that one. I’ve never seen a capacitor placed between the output of a sync stripper and SCART pin 20.

    #16769

    megari
    Participant

    Is this cable what you have? Please note that there is no mention of a sync stripper.

    #16777

    paulb_nl
    Participant

    That cable in the images he posted is just a CSYNC cable without stripper. Retrogamingcables always have the sync stripper on their PCB inside the SCART plug.

    Voultar made a video where he recommended a 470 Ohm resistor and 220uF capacitor on the CSYNC line for Genesis cables.

    Next step would be to try tweaking the various sync settings in the Sync options menu.

Viewing 15 posts - 1 through 15 (of 20 total)

You must be logged in to reply to this topic.