pokeymcsnatch (u/pokeymcsnatch)

pokeymcsnatch commented on Driverless semis have started running regular longhaul routes cnn.com/2025/05/01/busine... · Posted by u/harambae

ortusdux · 9 months ago

Is anyone working on an electric truck system where the battery is on the trailer? Many businesses are constantly rotating the same dry van trailers between hubs. If you charged the trailers at the doc during loading/unloading, the rigs could run 24/7, only stopping to swap trailers.

pokeymcsnatch · 9 months ago

Work/worked for a place that was doing this. There's a couple problems:

* More battery weight means less cargo weight

* Trailers are dumb; the standard hookup (in NA) is lights and air. I hear CAN is common in EU though.

* Trailers are cheap and almost disposable.

The trucking industry is very slow moving, and probably 20 years behind passenger cars. So changing any of this stuff, even though none of it sounds particularly major, is at least 15 years out to start. Then you're left with the hundreds of thousands of "legacy" trailers that need to be retired or retrofit. The tractor to trailer ratio out there is like 1:10.

One interesting use case for this though is refrigerated (refer) trailers. They're often diesel-electric so they can plug in to shore power. Add a battery to this and maybe you can dump the diesel motor. Again though, weight is an issue... diesel is an order of magnitude more energy dense than the best batteries we have.

pokeymcsnatch commented on Two new PebbleOS watches ericmigi.com/blog/introdu... · Posted by u/griffinli

sevg · a year ago

Is it actually open source though? The repository description may be outdated then, but it currently says this:

> This is the latest version of the internal repository from Pebble Technology providing the software to run on Pebble watches. Proprietary source code has been removed from this repository and it will not compile as-is. This is for information only.

pokeymcsnatch · a year ago

Just a guess, but Nordic pushes a proprietary bluetooth stack. You don't have to use it, but it's the fastest way to get up and running.

edit: not sure they use the proprietary stack... at the very least, it looks like they're in the process of switching to a free BT stack

pokeymcsnatch commented on The capacitor that Apple soldered incorrectly at the factory downtowndougbrown.com/202... · Posted by u/zdw

jopsen · a year ago

I've understood that capacitors can be used for timing, or smoothing a voltage after a power regulator (I think).

How/what does adding capacitance help with?

pokeymcsnatch · a year ago

Voltage spikes from line inductance, voltage drop-outs from line resistance. Basically you have little reservoirs of charge scattered all around the board (current flow isn't instantaneous in a real circuit).

It helps to always think of current draw in a compete loop, out the "top" of the capacitor, through your IC, and back into the ground side (this isn't necessarily what's happening physically). Shorter loop means less inductance, shorter traces less resistance.

pokeymcsnatch commented on Jaywalking legalized in New York City theguardian.com/us-news/2... · Posted by u/Thomashuet

hifromwork · a year ago

But we're talking about writing laws here. For example:

>with only minimal requirements made of the driver.

could easily be changed by changing the requirements.

pokeymcsnatch · a year ago

No law is going to physically protect you from a 2 ton hunk of steel.

pokeymcsnatch commented on Signatures of gravitational atoms from black hole mergers physics.aps.org/articles/... · Posted by u/thunderbong

ck2 · a year ago

Apparently I am not watching enough PBS SpaceTime because I still do understand what a "gravitational atom" might be.

They are not implying a particle that causes gravity right? Because I thought it is pretty well accepted there isn't a "gravaton" like there are photons.

They also don't mean atom-sized black-holes, so I still don't get it.

Hoping Matt does an episode on this so I can grasp it.

https://www.pbs.org/show/pbs-space-time/

pokeymcsnatch · a year ago

> I thought it is pretty well accepted there isn't a "gravaton" like there are photons.

Different branch of physics that we can't quite mesh with GR yet. A graviton is the quantized "piece" of gravity, like phonon is for sound/mechanical waves, or photons for EM. It exists as much as a photon or any other "messenger particles" exists, in that it's a useful mathematical model. It's not something we have isolated/observed with equipment though.

pokeymcsnatch commented on Using a 1965 Dutch rotary phone via VoIP raymii.org/s/blog/Using_a... · Posted by u/jandeboevrie

da768 · 2 years ago

There are adapters for handsets on Amazon, but interfacing to a phone could be harder as you have to provide DC power and deal with duplex audio on a single pair. If you're only using it as a mic, a 9v battery, resistor and decoupling capacitor might work.

An easier way could be to join the conference audio through SIP.

pokeymcsnatch · 2 years ago

Coupling capacitor, not decoupling, right? You want the AC signal and want to block DC.

pokeymcsnatch commented on This USB flash drive can only store 8KB of data, but will last you 200 years tomshardware.com/pc-compo... · Posted by u/marvinborner

lyu07282 · 2 years ago

To be fair it's just SPI and a big package, super easy to read even centuries from now. I don't think we will somehow forget everything about basic electronics.

pokeymcsnatch · 2 years ago

Just need 3 switches and an indicator light

pokeymcsnatch commented on Australian man says border force made him hand over phone passcode theguardian.com/australia... · Posted by u/uncooked3557

blackeyeblitzar · 2 years ago

And now TSA is trialing facial recognition at airports across the country. To my horror, nearly everyone just accepts it and follows the process instead of opting out.

pokeymcsnatch · 2 years ago

They present it in a way where it seems like you have to comply- "OK, now look into this camera and hold still".

If you don't read the signs (and from what I saw, no one does...), you may not understand that it's optional. The dishonesty is on purpose of course.

pokeymcsnatch commented on Ask HN: Why does everyone need to be an "Engineer" these days? · Posted by u/demosthanos

taylodl · 2 years ago

This is nothing new. The "engineerification" in the United States has been going on for the past 40-50 years. I still remember when "trash men" became "sanitation engineers" back in the 80's!

When someone tells me they're an engineer I ask about how hard the PE was. That's when you find out if someone is an actual engineer from a legal perspective or just affixing the term to themselves.

pokeymcsnatch · 2 years ago

Meh you don't need a PE to be an engineer. That's stretching the gatekeeping too far. PE is valuable for a lot of things, but not necessary for a lot of actual engineering work. Is a trained and working electrical engineer not an engineer because a PE isn't necessary to design and build sensors, loggers, etc?

PE essentially just means you can legally sign off on safety critical designs. Engineering is the application of math and physics to solve a problem.

Anecdotally, the handful of PEs I know are the pencil-pusher types. They're engineers on paper, but a critical skill for engineering is actually building stuff.

pokeymcsnatch commented on I made a new backplane for my consumer NAS codedbearder.com/posts/f3... · Posted by u/granra

dragontamer · 2 years ago

> This was my first time soldering DFN packages and they’re tiny! Because I don’t have a microscope or anything to visually inspect my soldering and these components were mostly just handling power anyway I just checked for shorts between power and ground and tried to take close-ups using my phone to see if I could spot any shorts. The technique that ended up working well for me to solder on these DFN packages without a stencil is to put what can only be described as way too much solder paste on the pads and then pushing the IC in the pool of solder, when the solder melts from the heat of my hot air station the IC will float on top and then I push down on it with tweezers and all excess solder will squeeze out and bead up, hopefully landing somewhere on the solder mask, where I can pick it up later once it’s solid.

This is positively an insane methodology for soldering. Fun, but insane.

I actually can imagine that it works, strangely enough. But I don't think you'd get much consistent reliability with this. More like it'd work often enough that its good for one-off projects.

pokeymcsnatch · 2 years ago

I extend the pads out from underneath the chip. Then it's easily hand-solderable if needed.