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  1. Hi all, I'm pretty new here but i figured that this may be the best place to discuss my issue.

    So I have had this TEAC MV-6096 VCR lying around for a while and recently I have decided to get a mini akai CRT TV.

    Had this idea that I could potentially capture my computer screen onto VHS (thought it would be cool)

    So I have this HDMI cable connected to my graphics card (GTX 1060 i think), and i connected that cable to a HDMI to AV Converter Box. These AV cables then lead from the HDMI to AV box, to the video IN on my VCR. The video out of my VCR leads to my CRT television.

    It worked for a bit, I was able to capture a test video of my computer screen onto a VHS tape! However there was no color, only a purely black and white image on the VHS playback. I turned off the vcr and crt television and decided to retry it the next morning (today). But upon booting up my computer and VCR/CRT, the image on the CRT appeared too be 'melting' sideways, in a sense that it was highly distorted and warped. The VCR's GUI (the time counter/ details that usually appear on the CRT) were all distorted too.

    At times, if for example, I open up a window on that screen, the CRT loses signal to the computer and the image disappears.

    What seems to be the cause of this? All the cables are properly connected, and the crt works still (when connected to just my computer screen).

    I've enclosed some videos in this thread of the melty screen to help get the point across.

    Any help would be gladly appreciated!
    Image Attached Files
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  2. The fact that you are a Radiohead fan.

    Jokes aside, are you sure that the VCR and the output as re the same format
    Last edited by rrats; 8th Apr 2022 at 02:17.
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  3. I love radio head haha, and no I haven't tried any composite sources, I have another VCR, might just test that one out just to see if it makes a difference
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  4. Formerly 'vaporeon800' Brad's Avatar
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    [EDIT: What resolution is your graphics card set to?]


    Originally Posted by hazza1912 View Post
    At times, if for example, I open up a window on that screen, the CRT loses signal to the computer and the image disappears.
    For troubleshooting purposes, change your PC to Dark Mode and try to eliminate as many bright parts of the displayed image as possible. It seems the wiggling is related to the brightness of the image being shown on the TV.
    Last edited by Brad; 8th Apr 2022 at 03:20.
    My YouTube channel with little clips: vhs-decode, comparing TBC, etc.
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  5. What you see are the classic symptoms of the video level being too high. I'll explain: composite video has two main components, the part you see (luminance and chrominance) and the synchronizing pulses. The 'sync' pulse level is below black and off the sides of the picture when viewed on a normal monitor, their purpose is to make sure the visible part stays in the right place on the screen. If you picture the signal levels, from zero to about 30% of the signal is sync, at the top of that is black and the remainder is visible with 100% being whitest white. (I am taking some liberties with the actual percentages to make it clearer). Your VCR has the ability to adapt itself to the range of input levels a consumer would be likely to connect to it. It does this using 'Automatic Gain Control' or AGC. Basically, it turns the levels down if they seem to be too high and turns them up if they seem too low, it gives greater tolerance to badly matched video sources. The effect you are seeing is caused when the video level is so high that the AGC can no longer cope with it. Your 'peak whites' are so high that to squeeze them in the available range, the AGC is shrinking the whole signal, including the sync pulses to the point where the picture creeps into the sync part of the signal and confuses the monitor or recording.

    It can be caused by several things but my first guess is you have an un-terminated video cable somewhere in your composite connections. Video is normally about 1 volt from bottom of sync pulses to tip of white but in order to match normal 75 Ohm video cable impedance, it is actually produced at 2V levels and halved back to 1V by the termination resistance at the load end. If that terminator isn't there, the video will stay at 2V level and cause the overload you see. If you can get hold of a 75 Ohm resistor and wire it between the composite video and ground connections at the VCR input it will probably fix it. If that doesn't work, try wiring it at the input to the monitor instead, the same problem can occur wherever video is carried along a cable.
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  6. Hey thanks for the heads up! Really appreciate it, ill hook up a resistor and let you know what happens!
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