HN user

tesseract

1,953 karma
Posts8
Comments683
View on HN

there is that CO2 on the air that we actually want to get rid of

For this reason I have long been slightly baffled that development of compostable/biodegradable bio-based plastics is such a priority in materials research. Sure, it's interesting in the very long run, but for the foreseeable future, converting atmospheric CO2 (via plants as an initial step) into a long lived, inert material that can just be buried after an initial use seems like a benefit.

Many of those big bells in other cultures are on fixed mountings (in a carillon, for instance). The idea of mounting the bell on a rotating wheel - which imposes limits on what music can be played due to the rotational inertia of the wheel, therefore leading to a unique style of composition - is distinctively English.

Tom Lehrer has died 12 months ago

A fairly intellectual audience, in the 50s and 60s when the space race was big news and von Braun's Nazi past was recent history? I'd guess a majority.

My family had a small B&W CRT that fascinated me with its image quality, in that it always reminded me more of a b&w photo than color CRTs reminded me of color photos.

The problem of a finite dot pitch interfering with image quality, especially on small displays where the dots were necessarily larger relative to the image size, is what motivated Tektronix to develop field-sequential color CRTs which they used in their digital oscilloscopes in the 80s and 90s. JVC also used the technology in some professional broadcast video monitors. Basically it was a B&W CRT with a changeable (liquid crystal) color filter in front of it. The R, G, and B channels would be shown one after another with the corresponding filter activated, in a similar manner to a color wheel DLP projector.

The real project is the sense of accomplishment we gained along the way, or something like that.

But anyway, there are institutions like the Craftsmanship Museum <https://craftsmanshipmuseum.com/> that exist to present this kind of passion project to the interested public. That one in particular came out of and is still very centered on the hobby machinist and model steam engine community... if there's not already something similar for electronics and computing type projects, it definitely seems like maybe there could/should be.

In my opinion it's not always the most readable codebase, due to some idiosyncratic style choices, but it definitely has the advantages of being small and focused.

It was based on FreeRTOS, but FreeRTOS at the time was extremely bare bones and only provided a preemptive scheduler, task management, and synchronization primitives. Everything else (memory management, I/O, ...) had to come either from whatever libc implementation was in use, or be built from scratch.

I have been happy with my pepper mill with a Crushgrind mechanism.

(The mill happens to be from Normann Copenhagen but Crushgrind supplies mechanisms to a number of pepper mill manufacturers as well as selling their own.)

Flash as an animation tool and applet platform was already on the downswing when the iPhone happened, though.

The consumer demand for Flash on mobile seemed to be mostly about video streaming, because at the time Flash was experiencing sort of a second life as the least-bad way to do streaming video on the web. In that context Apple's point of view of "as an industry let's finally fix browser-native video streaming, rather than being stuck with Flash forever" seems pretty reasonable.

Ben Rich, and yes: he was the 2nd director of the Lockheed Skunk Works.

I think the book may have been out of print for a while but it's easily available now.

If you apply a constant current to a capacitor, the voltage across the capacitor will increase linearly as the capacitor stores energy in the electric field.

If you apply a constant voltage to an inductor, the current through the inductor will increase linearly as the inductor stores energy in the magnetic field.

Perhaps part of why the intuition can break down is that in real life, inductors tend to be much "leakier" energy storage devices than capacitors. If you store some energy in an inductor and then change the voltage across it to zero (practically: short its terminals together), in theory a perfect inductor will maintain a constant current forever and the energy stored does not change. In practice inductors (with an exception for things like superconducting magnets) are made from wire that has a resistance, and so the current in a real shorted inductor will eventually decay to zero. This means that in practical terms inductors are mostly only useful for short term energy storage. On the other hand, real-life insulating materials (like air, vacuum, or Teflon) can can be pretty close to perfect insulators allowing real capacitors to store energy more or less indefinitely... certainly on timescales of years.

The meme started as eating paste, back when that meant wheatpaste (made from flour and water). In that context it's less surprising that kids might try to eat it!

I wonder if there's been a bit of a conflation with the other meme, about sniffing glue, which has also lost much of its context considering that rubber cement and other similar types of glue which contain volatile solvents are also less widely used than they once were.

Blue Ball Machine 2 years ago

Yes, it does. There's also audio of Don LaFontaine reading the ad in his signature movie trailer style [1] - I'm a little unclear on whether the YTMNDer requested it from him or if he came up with the idea himself, but it also predates the actual movie by a fair number of years.

[1] https://lafontainesafety.ytmnd.com/

Yeah the advice to "use trimmings!" seems very based in a restaurant situation where (a) lots of vegetables are getting prepped regularly and (b) cutting techniques are based on the goals of speed and uniform product, so you'll see things like squaring up a vegetable into a cuboid before dicing it... which produces "scraps" that aren't wasted, because they can go into a stock!

So much peripheral functionality has been pushed inside the CPU that a modern desktop motherboard is from one point of view essentially a fancy DC-DC converter that happens to also handle I/O port breakout. The motherboard has to translate 12 volts at 10-ish amps from the PSU, into a highly stable 1.2-ish volts at 100-ish amps for the CPU power rail.

There were/are a couple of aerospace surplus shops in the area. Apex and Norton are the ones I'm familiar with. The supply comes from the SoCal aerospace industrial base and a lot of the demand is indeed for movie props. It's a fortuitous pairing - the prop rental business seems to be keeping them going to some extent whereas a lot of industrial surplus businesses in other parts of the country seem to be struggling these days.