Been doing some work on my Pig Out including some monitor work and I haven't been able to figure out this jitter. It's only been happening rarely while I've been working on it in my shop. I believe I discovered tonight that it's when warm. Once I thought of that, I closed up the cab and ran it for a couple hours, and sure enough it happened. I replaced Q9 and I had another IC3 so I figured I'd try that too (saw a post about jitters that was solved by this). I replaced VR3 (v pos) for an unrelated reason, but it happened before I did that too. Also happened before and after recapping.
I have installed a resistor in parallel with R83 to lower the value to 291 because I couldn't center the image properly (Pig Out has an off center plastic bezel for some reason). I've seen posts about lowering R83 for moving the vertical center down further than the pot will allow, so probably that's not causing it although I might pull that out next just to be sure.
It seems like maybe some sort of resonance because the pattern is always exactly the same and just continues on and on and on.
Any known causes for this particular jitter? I haven't found anything quite like this here (lots of other kinds of jitters/bouncing/shaking though).
Probably not hard to see, but the easiest way to watch this is to watch the bottom of the letters of "and press join" relative to the top of the black plastic bezel.
EDIT: to be clear, this is not some sort of blooming issue where the overall size is growing and shrinking. The entire image is bouncing up and down. Bottom (as seen in the video), top, and middle.
I have installed a resistor in parallel with R83 to lower the value to 291 because I couldn't center the image properly (Pig Out has an off center plastic bezel for some reason). I've seen posts about lowering R83 for moving the vertical center down further than the pot will allow, so probably that's not causing it although I might pull that out next just to be sure.
It seems like maybe some sort of resonance because the pattern is always exactly the same and just continues on and on and on.
Any known causes for this particular jitter? I haven't found anything quite like this here (lots of other kinds of jitters/bouncing/shaking though).
Probably not hard to see, but the easiest way to watch this is to watch the bottom of the letters of "and press join" relative to the top of the black plastic bezel.
EDIT: to be clear, this is not some sort of blooming issue where the overall size is growing and shrinking. The entire image is bouncing up and down. Bottom (as seen in the video), top, and middle.
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