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Ask HN: What did you find out or explore today?

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Re: Ask HN: What did you find out or explore today?

#231

Post by butlike »

cess11 wrote: post #136
satvikpendem wrote: post #127

Earlier quoted context omitted.

This was always a flawed quote because even before such a realization, people still did novel things (and literally flew to new places), much the same as birds. And the answer is still the same for birds and humans, the constraint of resources. If you have enough then by all means, fly.

The point is for you to take a look at yourself and how you are currently spending your time, from the assumption that you could do something different.

Ehhh, I feel like resource is still a big part of it. I like to travel, not above all else, and would like to do more of it, provided. But provided is not.

Re: Ask HN: What did you find out or explore today?

#232

Post by Findecanor »

techiferous wrote: post #185
torben-friis wrote: post #92

I got a handheld emulator console as a Christmas gift. Configuring shaders that emulate crt TVs, I realized I had no mental model of how those TVs worked at all. I’m used to “pixels are three little lights combining rgb colors”, which doesn’t work here, so I went on a rabbit hole and let me tell you, analog TVs are extremely impressive tech. Getting an electron beam to hit a glass, making the chemicals on it spark, c…

Don't forget how they found a way to squish closed caption information into analog broadcast. The electron beam traces a path on the CRT display by drawing the odd lines from top to bottom (which draws half the image) and then the even lines (the rest of the owl) from top to bottom. While the electron beam is repositioning itself from the bottom of the screen to the top of the screen, there is a brief period of time…

Teletext used the vertical blanking interval too. It consisted of numbered pages of text, each number input on the numpad on the remote control as a form of hypertext. Page after page was transmitted after one-another, repeatedly. It was sometimes used for subtitles, with some pages with a transparent background. Better receivers cached pages so you wouldn't have to wait for its next transmission when going to another page...

Digital television formats adopted the framing from analogue formats and sends the same data in digital form within the vertical blanking interval. Many channels have stopped offering teletext. One network here in Sweden still uses it to deliver news, and I often prefer that format because the articles are concise and distraction-free.

BTW. I was once asked to hack together a system for using data in the vblank period to control relays at a remote site.

Re: Ask HN: What did you find out or explore today?

#233

Post by clarencehoward »

I learned about fan-out, and just how the average size of groups in messaging servers affects their load. It is pretty basic stuff I guess but not something you think about unless that is your jam.

I was stress testing a server I made and noticed a discrepancy between two tests. In on test 15 virtual users could send 450msg/sec (not realistic I know) for about 6750 incoming messages per second. In another, 1000 users sending a message about every two seconds was the limit, about 500msg/sec incoming.

Took me a little bit to figure out why, the outgoing messages between the tests were wildly different. In the smaller user tests the groups were about 3 on average, in the larger one they were 30. Group size is effectively a multiplier on incoming msg requests so when looking at the total traffic it was much closer between the two tests 15k and 20k.

Re: Ask HN: What did you find out or explore today?

#235

Post by gglitch »

GarnetFloride wrote: post #22

Reading up on the history of information management, and the real killer app for paper was double-entry bookkeeping, which made Venice rich and contributed to starting the Renaissance.

Any titles or resources you have found particularly interesting?

Re: Ask HN: What did you find out or explore today?

#237

Post by Findecanor »

schnitzelstoat wrote: post #149
torben-friis wrote: post #92

I got a handheld emulator console as a Christmas gift. Configuring shaders that emulate crt TVs, I realized I had no mental model of how those TVs worked at all. I’m used to “pixels are three little lights combining rgb colors”, which doesn’t work here, so I went on a rabbit hole and let me tell you, analog TVs are extremely impressive tech. Getting an electron beam to hit a glass, making the chemicals on it spark, c…

> Turns out that the logic in consoles of the time was tied to the speed of the beam, which in turn used alternating current’s frequency as a clock. This means that since European current changes 50 times per second rather than 60, our games played in slowmo (about 0.8x). American sonic was so much faster! And the music was so much more upbeat! Wasn't this the reason behind different versions of the game for PAL and…

The vertical resolution was also different. Some games developed for NTSC got black bars, or a silly banner in the PAL version. Many PAL games were not ported for NTSC regions at all.

Re: Ask HN: What did you find out or explore today?

#238

Post by cafard »

I found out that, as I thought, I'd probably rather have read Frederick Law Olmsted on his travels in the antebellum South than Tony Horwitz (Spying on the South) on Olmsted on etc.

I found out that falling out of bed is not just for children, and that bringing an adult's body mass is not an improvement. I don't suppose that I'd fallen out of bed since LBJ was president.

I found out that YouTube has some interesting notions about me: the opening ad on a rather bland video was anything but bland, astonishing even a jaded old man.

Re: Ask HN: What did you find out or explore today?

#239

Post by Findecanor »

whycome wrote: post #140
torben-friis wrote: post #92

I got a handheld emulator console as a Christmas gift. Configuring shaders that emulate crt TVs, I realized I had no mental model of how those TVs worked at all. I’m used to “pixels are three little lights combining rgb colors”, which doesn’t work here, so I went on a rabbit hole and let me tell you, analog TVs are extremely impressive tech. Getting an electron beam to hit a glass, making the chemicals on it spark, c…

What other sci fi technology is being lost on us now? I always that the complexity of the local-battery-powered copper-cable telephone exchange system was bonkers. It was the backbone for all our landline calls.

The telephone system also powered the phone, and often worked when the power grid did not.
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