Koryuu s-video interference

NewHome Forums Koryuu Transcoder Koryuu s-video interference

Viewing 4 posts - 31 through 34 (of 34 total)
  • Author
    Posts
  • #42285
    leewrigley
    Participant

    Managed to get it fixed with help of the store owner and picture looks sharp but I too am still experiencing interference similar to noctuas – maybe slightly different that what my screenshots looked like before as now the lines are moving darker diagonal lines and not just the composite interference.

    #42287
    megari
    Participant

    @leewrigley I’m glad you got the missing chroma fixed (the solder blob did look relatively harmless, though, at it seems to make the correct connection).

    Looking at the photo you shared, I may have gotten an idea. I wonder if the moving diagonal lines are caused by a ground loop in your case. They seem to be a common, specific symptom peculiar to ground loops. Why that came to my mind is that at least the top side of the PCB at the console end of your cable seems to have no ground pours, rather than individual traces connecting to ground. Depending on what the other side of the PCB looks like, the cable itself may be susceptible to ground loops.

    Not sure about this, though, and even if a ground loop turns out to be the culprit, how to best fix it. It is rather easy to make it worse by introducing additional loops, though…

    #42288
    leewrigley
    Participant

    @megari it’s a weird one for sure, because of the high quality cable you would expect it to be a lot better picture quality wise, I almost feel as if it’s a different problem entirely in a way to what I was experiencing before (I might be wrong) but now instead of seeing the checkerboarding throughout the image, now what you see is dark moving diagonal lines (visible especially on the red of Mario’s hat etc, tomorrow I might try get some new pictures or even footage if the camera picks it up well.

    Would be good if anyone else on the forum maybe knew more about potential for ground loops or any other solutions for this.

    #42378
    megari
    Participant

    @leewrigley I thought about this a bit more. Still with the working hypothesis of a ground loop-like issue and/or mains frequency leakthrough, another source of the diagonal lines might pertain to the power supply. What kind of power supply/supplies are you using for your device(s)? Have you checked if their output looks relatively clean?

    I assume you are in an area with 50 Hz mains, given that you are using a PAL N64? If not, then the 50 vs. 60 Hz disparity could cause a diagonal pattern if the mains frequency were to leak into your AV equipment. Other power supply issues could also cause similar effects.

    Also, concerning common causes for ground loops, are all your devices connected to the same ground? Is any of your devices not grounded at all (TVs, VCRs etc. often are not)? Is there any source your devices might get a second, different ground from? For instance, if some AV equipment is connected to an antenna, it might have a ground with a different potential from that of the mains grid, in which case one of the grounds needs to be disconnected.

Viewing 4 posts - 31 through 34 (of 34 total)
  • You must be logged in to reply to this topic.