Science Porn

[vorlon13]

The audio signal was coded as a series of black and white dots and recorded instead of the video on the tape.

If you turned on the TV, this is what the audio recording looked like:

[Anomalocaris]

On a related;

over the years we've had birds get in the double garage, and despite opening both garage doors and both people doors, the birds don't have the brain processing power to exit the garage before they starve to death.

I was in the garage yesterday and noted some of those scary blue/black wasps flew into the garage, reconnoitered the facility, and then left without me having to do anything.


Why the effing birds so stooooopid ?

How do you know those birds didn't philosophically contemplate their own existences, weighed their options and then calculated that your garage is the mathematically optimal place in which to seek their own deaths?

[Anomalocaris]

OK, rephrase:

why the damn bugs so smart ?

Evilution!

"Wasps first appeared in the fossil record in the Jurassic, and diversified into many surviving superfamilies by the Cretaceous. They are a successful and diverse group of insects with tens of thousands of described species; wasps have spread to all parts of the world except for the polar regions"


"True birds first appeared during the Cretaceous period, around 100 million years ago."

One of them has had more time to develop some skillz.

Well, crows are have cognitive powers similar to chimps. The wasp knows how to get out of an open door.

[vorlon13]

The 6 vertical areas are the L and R channels recorded IIRC, in the sequence of L, R, L, R, L, R and there was an offset in time between all of them so if a crease on the tape went over the heads, the error correction bits (the right side 1/4 of the pattern) could fix the drop outs as they were not simultaneous in the played back sound.

BTW, the error correction was robust, if the tape was damaged and you played it back and didn't hear any clicks or dropouts, it meant the error correction restored the waveform to what was originally recorded.

There was a limitation to the technology however, playing back the recording and copying it onto another machine could not be done in the digital realm, you would incur a D to A conversion and another A to D conversion if you re-recorded it another digital recorder of the era. The VCR did not have either a coax or optical digital output.

The tapes could be copied as video tapes (in the analog realm) and an SP original could be copied in SP and played back OK, the machine didn't do LP, and SLP originals would play, but the copies were unplayable.

I made 6 hour mixtapes, on VHS in SLP from CDs. Worked well enough. My recorder doesn't work any more (machine won't load a tape anymore), I suspect all the digital stuff still works) however, the machine also recorded a simultaneous stereo VHS Hi-Fi track, and that is still playable on any stereo Hi-Fi VHS machine.

VHS Hi-Fi had great audio specs, BTW, way better than cassettes, and rivaling the digital PCM mode. Probably about as good as analog recording ever got. VHS Hi-Fi was also recorded onto the picture area of the videotape, but the Hi-Fi heads were physically skewed or offset from the video tracks, or used a frequency the video didn't use, or was recorded in a deeper layer of the tape, I can't recall precisely how it worked.

[vorlon13]

On a related;

over the years we've had birds get in the double garage, and despite opening both garage doors and both people doors, the birds don't have the brain processing power to exit the garage before they starve to death.

I was in the garage yesterday and noted some of those scary blue/black wasps flew into the garage, reconnoitered the facility, and then left without me having to do anything.


Why the effing birds so stooooopid ?

How do you know those birds didn't philosophically contemplate their own existences, weighed their options and then calculated that your garage is the mathematically optimal place in which to seek their own deaths?

Well that is a grim outlook on god's little creatures now, ain't it ?

[pocaracas]

Wingtip vortices!

[pocaracas]

This is just a link.

This link will take you to the vastness of our solar system.
It will give you a side scrolling page, where the moon scales to one pixel on your screen... keep scrolling!


(PS: I may have shared this on AF a long time ago... but it's now worth bringing back)

[SteelCurtain]

Those wingtip vortices cause a lot of drag and effect fuel mileage pretty heavily.

That's why you see winglets (those little upturned tips on the wings) on pretty much all new aircraft. My senior thesis was to study the effects or a triple winglet (85°, 60°, 45°) on fuel economy and induced drag on a standard NACA airfoil. I wish I had access to that hard drive. It was a cool hypothesis and we got some awesome pictures and wind tunnel data. That computer is sitting in a basement in Arnold, MD. I wonder if it would even fire up after 8.5 years?

[pocaracas]

Still think Galileo was wrong?

[SteelCurtain]

Maybe it's private? Can't see it, mate.

EDIT: Your earlier wingtip vortices pic is broken, too.