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Thread: Capturing Pixel Data Signal

  1. #1
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    Default Capturing Pixel Data Signal

    On occasion I’ve found myself wondering how the signal is looking at a pixel input.

    Is there a relatively cheap way to see the signal quality? Preferably a method/device that can be used in the middle of the yard.

    I know you can get this information on an O-Scope. Was hoping for maybe something that could plug into a laptop or something. Can’t imagine what else I’d use an O-Scope for or I’d just buy one.

  2. #2
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    Default Re: Capturing Pixel Data Signal

    There are quite a few computer oscilloscope interfaces out there. Just do a search for "computer based oscilloscope".

    Note that there are just as many opinions as to if they are good or not. You will have to decide.
    Last edited by algerdes; 06-22-2018 at 08:22 AM.
    "Never Give Up. Never Surrender!"
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  3. #3
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    Default Re: Capturing Pixel Data Signal

    Saleae is my first choice, but its not cheap. I know there are some cheap knock-offs on ebay but I can't comment on how well they work in compared to the real thing.

  4. #4
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    Default Re: Capturing Pixel Data Signal

    There are a lot of USB logic analyzers. You don't really need an oscilloscope unless you want to see the actual voltage.

  5. #5
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    Default Re: Capturing Pixel Data Signal

    Hi, just some quick thoughts. A logic analyser is not going to help you if you are looking for signal degradation. As mentioned above the Saleae unit is excellent (even the clones work well) but all this will do is pick the bones out of the incoming signal and make its decision as to whether this is a one or a zero and then display it as a ‘perfect’ trace. Not much help if your pixels don’t recognise the same levels or exclude the same amount of noise. You will need as you stated a scope to really see what is happening and given that the data is transmitted at 800Kh cheap ones are not going to be much use (I know I have both).

    I may be wrong but if your thinking is to check how close to the cable run limit you are, it might be more effective to rig up an inline box that switches in additional lengths of cable, for example 0, 5ft, 10ft, 15ft etc. With this you can quickly do a real test as to how close to the limit you are using the exact cable in your display. This is not going to show your “signal quality” as requested in your post but will give you an idea of how for under the maximum distance you are for your equipment and location.

  6. #6
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    Default Re: Capturing Pixel Data Signal

    Do any of you think/know if this scope will work and would you pay $900 for it? It's a Fluke 199C Scopemeter

    00505_DP7LWY8F7L_1200x900.jpg

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