pokeymcsnatch

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.

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

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.

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

> 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.

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

Just need 3 switches and an indicator light

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.

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.

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

> TL;DR - Your deep cycle battery approach may not prove to actually be worthwhile, consider working out the car-as-generator hookup plan in advance.

Ha yep, learned that the first time and was ready to go with an extension cord the second time I needed this setup. First time, I had a stash of 3 batteries but I didn't realize how much power the blower motor would draw, so I was charging on the car and swapping out batteries as needed. Did that the first day then rigged up cords for day 2. Halfway through day 3 we got power back.

My strategy is a deep cycle car battery and harbor freight inverter to run the blower motor. You get a long enough extension cord and you can use your car as an emergency generator.

The illness doesn't but the virus might.

I'll bite I guess. I use Calibre pretty regularly. I think a general way to put it is that it's not for "casuals". To understand a lot of the functionality outside of the basic inventory management stuff, you have to be a little bit of an enthusiast. For some examples: You have to know about different ereaders and their formats and how they differ, the differences between metadata sources, and dozens and dozens of configuration options if you're trying to convert a book to work well on your device.

Also, there's definitely something "off" when it comes to using it intuitively. I have to devote a lot of brain power to searching for functionality AND trying to comprehend exactly how those pieces of functionality are going to affect my library data.

Maybe it's too powerful of a tool up front or something. It could benefit from a "basic view" maybe?

None of these are complaints from me, I'm a happy user. I'll just echo some other commenters in wishing for a more robust network interface (whether that's just an API, or a more hashed out front end). I'd like to easily share my library with people or just other devices while on-the-go, and Calibre has all the device formatting functionality built-in.

Truck manufacturers measure fuel efficiencies to the tenths and compete on that. At highway speeds, ICE engines win over a pure electric system, so throwing in another conversion step hurts. For city routes, pure electric is better than diesel-electric.

So in general, the disadvantages of a diesel-electric system outweigh any advantages when you take a look at how trucks operate.

New trucks have "automatic" transmissions (not torque converters- they're more like automatically shifting standard transmissions), so no manual shifting required.

Somewhat related, but refrigerated trailers ("refers") often use a diesel-electric system because it's easy to plug in to shore power and cut the diesel engine.