Bad Apple or Happy Radio Day, geeks

Today there were very few congratulations on the professional holiday of some geeks, I would like to cheer up myself and the rest, get something like my favorite warm lamp ... And yes! it will be a green oscilloscope pleasing to the human eye.

As everyone knows, the oscilloscope is very simple, it is usually used to observe signals in real (now, not only) time, oscilloscopes develop, become digital, but this has not always been the case. Unfortunately, the first generation of oscilloscopes with a nice analog green color is dying, and so much more can be done with them. So why not today.

In addition, to show the signals, I would like to get something more tangible on it and why not Bad Apple, and why not in a “simple” way.

Bad apple

The idea came to mind is extremely simple (we repent that it has already been described somewhere), use a VGA video output, namely the color signals R, G, B to encode the position of the beam. One, for example, R is used to deflect the beam along X, the second G is for Y, and B is used to turn off the beam during the return stroke of the line and frame.

But Bad Apple itself is raster-raster, but you need to translate it into a vector. Since we are more than once programmers, sprinkling ashes on our heads, we decided to hammer in nails with a microscope, namely, we took a matlab and using the bwtraceboundary function identified the contours of raster objects, decoded, filtered, and the resulting vectors bypassed. Something was filtered.

And, to our surprise, we got a pretty clear outline. For radio technicians, who are more likely to “you” in image processing, without deep digging into mathematics, there has been very even progress.



Further, the obtained vectors were overtaken to bypass the beam, and already the beam was stretched to such a raster image of the frame. This is the same picture as above, but the position of the point in the image is already color coded.



Then the 16 megabyte source Bad Apple was transferred to the 13 GB Green Apple c with this result =)))

Happy Radio, colleagues! We don’t know about you, but at least we spent this day surrounded by warm lamp technology.


PS: Some may correctly notice that C1-94 does not have the ability to offset the beam along X, the image should have been shifted half a screen to the right, but this is not a montage, an external operational amplifier has been added to offset it.

Well, and as some usefulness, why this might be needed.

The most pleasant bonus is the opportunity to make a green clock for yourself, which in the title of the article, would still be equipped with an alarm clock and would be a class in general, I would set at home, despite the size.

Another nice bonus when it is possible to form an accurate scan on the oscilloscope screen is a rather detailed measurement of the exposure time of a video or camera.
For example, if you create just such a scan:



where each stroke is 10 µs, it is possible to determine the exposure duration with an accuracy of about 5 µs, while with a duration of a few milliseconds, if you create several such tables, you can measure the camera’s exposure in different intervals from a few microseconds to about 1/25 second (and even more )

The measurement on the video camera looks something like this:



here the exposure was 520 microseconds. Unfortunately, the afterglow of the phosphor is a bit in the way, but this is a matter of practice and choosing an oscilloscope with minimal afterglow.

So like this =) I hope it was interesting and at least a little brightened up the everyday life of gray quarantine.

Yours, Pyhesty, who came up with the idea, and Aleksey, who realized the beautiful Green Apple on C1-94.

And Truly Popov! =)