It annoys me far more than it probably should that the only contexts in which I regularly encounter Ergs are supernovas and rowing machines. You know, two events whose approximate levels of energy are separated by only a few dozen orders of magnitude. Absolutely makes sense to measure them both with the same non-SI unit.
I learned something interesting while out for a walk at night recently. I was walking across a lawn and noticed all these little sparkles catching the light from my flashlight. Thought maybe sprinkler droplets which hadn’t evaporated yet.
I looked closer, and nope! Spider eyes! This lawn had a *lot* of wolf spiders. Very cool.
My goodness, the amount of cargo-culted nonsense in IP networking is ridiculous. Currently dealing with yet another person who insists the router ID needs to be an address on the router and it should be a loopback. Absolutely incorrect, otherwise you would never be able to run dynamic routing on an IPv6-only system!
Starting to think we need a Networking for Network Administrators book. @mwl
Two of my banks recently implemented #passkeys, and the contrast between them is stark.
I went to log in to one and they wouldn’t let me in until I “verified my identity” using a text message code to a phone number they apparently got from some data broker or by uploading my government ID and a video (obviously not happening). When I eventually got their support to let me in, the site forced passkey setup with no options at all. There’s no way to set up more than one passkey, no way to revoke access from the one I set up, and no way to log in via password anymore. They made every single decision in the most incorrect way possible. Utter garbage. Unfortunately, they’re the only option available to me for the particular account I have, so I’m stuck with them.
Meanwhile, Wealthfront reopened a support ticket I filed years ago requesting passkey support to let me know they had added it. I logged in with a password, and the site offered to set up a passkey. In my user profile’s authentication page, there’s a section listing all my passkeys (and app-specific password names, etc.). It allows me to specify friendly names to track which is which, add more, and remove keys I no longer control. It’s pretty much perfect!
About to hard-wire a dashcam for a friend, and I started by researching both the vehicle and all the hardware we’re planning to add. This uses a type of fuse tap I haven’t used before, but it’s basically the same as other fuse taps. While confirming that, though, I have run across a *ridiculous* amount of misinformation about fuses and fuse taps.
First, let’s talk about why cars have fuses at all. Wires in a car are specified to carry a particular amount of current safely. If the accessory at the other end of the wire breaks, it might create a short circuit, allowing the accessory to draw far more power than it ordinarily does. The higher current causes the wire powering that accessory to heat up, running the risk of an electrical fire (incidentally, this is an overload, as in the wire is carrying more load than it is rated for). Fuses prevent this situation. Once the accessory starts drawing too much power for the circuit, the fuse blows and there’s no more circuit. They don’t protect accessories—they protect the rest of the car from an accessory which has already failed.
Many (but not all!) electrical circuits in cars get one pole from the car’s frame or chassis, and the other pole is a wire from the accessory to a fusebox. The fusebox routes the wire to one end of a connector for the fuse. The other end of the fuse connector goes to a bus bar in the fusebox. The bus bar is a big, continuous piece of metal which can usually carry hundreds of amps (since it’s a part of all of the circuits handled by the fusebox).
Now, back to the taps. In general, fuse taps replace an existing fuse with two fuses with independent outputs. One output goes right back where the original fuse was, and you plug the original fuse into a slot on the tap. The other output has a whole separate fuse. Three pins: one common, one fused with the original fuse, one fused for the new circuit. Simple, right?
Where this gets complicated is having a common pin makes them directional. Lots of people are apparently confused about just what this means. In short, if you install the tap in one direction, you get two independent circuits. Flip is around in the same socket, and *both* paths depend on the current through the original fuse.
This is a little like the mechanism behind the 1981 Hyatt Regency walkway collapse in which a particular set of nuts were bearing twice as much load as they did in the design. Fortunately, installing fuse taps backwards can’t directly be deadly, it just might blow the original fuse more readily than you expect. With how big a hassle some cars make it to get to the fusebox (in my friend’s car, the interior fusebox is under the carpet in the passenger footwell), this can be seriously annoying.
The right direction to install the tap depends on how the fusebox is wired. You may have heard of “negative-frame” or “positive-frame” cars. Those approximately refer to which side of the 12v battery is connected to the frame. The fusebox generally has the other pole on its bus bar. Either negative frame with positive fusebox or positive frame with negative fusebox works, you just have to connect the correct pole from the accessory to the wire to the fusebox. Most cars are negative-frame, so you have a big +12v bus in the fusebox, fuses leading to wires, wires going to accessories’ +12v input, then the accessories’ ground input going to the frame or chassis.
The tap’s common pin is functionally a tiny bus bar, and it should be connected to the fusebox’s bus bar. In a negative-frame car, when you plug the tap in with the new accessory’s fuse but without the original fuse you’re replacing, the output for the new accessory should be +12v relative to the frame of the car.
It seems appropriate that in spite of the tarp, we have a photo of workers cleaning the P off of the Kennedy Center.
It’s more than a little weird that Apple decided to demonstrate their new LLM-centric features with a demo application centered around origami, a hobby rather famously being wrecked by LLMs generating impossible models and garbage directions.
Did a lot of suspension work on a friend’s Honda Element. Such a cool car. Replaced the rear coilovers and rear sway bar links. Was going to replace the control arms too, but the inner bolts have very limited clearance around them. None of my sockets quite fit, and I didn’t have the right combination wrenches.
Oh well! Suitable combination wrench set is on the way. I’ll do them next time, along with the outer tie rod ends. Maybe front struts.
Had to solder about 220 through-hole joints today (headers onto some microcontrollers). I do this pretty infrequently, so it takes 20-30 joints to get back in the groove. Once I did, though, everything else came out looking like a machine did it. Good wetting of the pads, and clean exponential curves to the pins. I’ve missed physical electronic work like this. Once I have a house, maybe I’ll get a hot air pencil.
Got the low-profile Allen wrenches and a taller jack, and replaced the snub mount bushing this morning. When the mount finally came off, 20 years of accumulated road dirt fell out and blew directly into my face. Always wear your eye protection!
I guess my next tool is technically going to be a set of low-profile Allen wrenches. The car’s an Audi C6/4F, and it also needs a new bushing for the snub mount (connects the front of the engine/transmission package to the front of the frame). The OEM bushing is some kind of foam like the shock bump stops which totally disintegrates by 30k miles. Metal-on-metal makes for rough shifting.
There’s very little clearance above the bolts on the engine side of the mount, and my socket bit set won’t fit.
Just finished two hours of Pilates (replacing the rear shocks on a car I’ve never done suspension work on before). I am exhausted and filthy, but it worked out!
Again, I’m incredibly glad I have a nice impact wrench. It made super quick work of the wheels. The lower bolt through the shock was brutal, but it gave after a few seconds.
I think my next tool is going to be a power ratchet. The wheel well liners involved a ton of T25 screws at awkward angles.
I just learned the personal trainer in the first season of Fargo is played by Glen Howerton, who also plays Dennis in Always Sunny!
The more I read about this White House Correspondents’ Dinner situation, the more it feels like an Always Sunny plot with Stephen Miller as Dennis (of “the implication” fame if you’ve never seen the show).
Test equipment is also so much better and more accessible. My multimeter has been annoying me (it takes *six* AA cells!), so I got a combination multimeter, signal generator, and oscilloscope for under $75 shipped. The oscilloscope part has limitations, but it’s extremely capable for the price. 50 MHz bandwidth on each of two channels, Y-T and X-Y modes, the ability to do math on the two signals and show the result as a third trace, live FFT, the ability to save a waveform for later viewing on a computer, all kinds of stuff.
Logic analyzers have also gotten really good and really cheap.
I have a small new project which needs a little compute and a Bluetooth transceiver, so I picked up a pack of ESP32-C6 “supermini” boards from a Chinese seller. I’ve seen boards like this pop up then disappear when the seller moves on to something else, but they also sent a solid documentation package. Schematics, board footprint, datasheets for all the chips down to the voltage regulator. They were something like $3.20 each.
The microcontroller world is so much better than it was when I was learning.
A lot of people criticize iOS and Android for making it harder to learn the low levels of how computers work. I’ve got to say, though, modern microcontrollers are so cheap and powerful it’s unreal. My first microcontroller was a 4 MHz PIC with 16 *bytes* of RAM and 256 *bytes* of storage for the program.
Today, for $19, you can get a pack of three ESP32 S3 units. Two primary cores at 240 MHz, a third core at ~20 MHz, 512 kB of RAM, 384 kB of main storage, 8 MB of SPI flash, all kinds of built-in peripherals (UARTs, SPI, I2C, even WiFi and Bluetooth). Learning how computers actually work has never been easier for people who want to know!
Fun pi fact which too few people know: the digits actually do follow a pattern! In 1995, Simon Plouffe discovered a formula for pi which he used to create what is called a “spigot algorithm”. This algorithm allows a given digit of pi to be calculated *without* calculating the preceding digits. Originally, it only worked in hexadecimal, but he later discovered another algorithm for a given digit of pi in decimal.
The known spigot algorithms for pi are non-constant time. Calculating the millionth digit takes longer than the thousandth. Still, they’re interesting because they have much lower memory requirements than other methods of calculating a value for pi.
It’s fascinating that apparently, Epstein was personally connected to basically all of the negative social movements in the US and Europe over the last 25 years. Several friends shuttered an MLP fandom convention they ran because they couldn’t deal with the Nazi problem. Epstein was the cause of this Nazi problem in the MLP fandom.
Deeply bizarre to see laid out like this. The guy was borderline illiterate! His influence was due to his friends, but why was anybody friends with him in the first place? What did they bond over before he could afford pedophile island?
Found out someone I know had never seen any of the Terminator movies. Watched the first last week, and the second tonight. The scene in the second where Sarah sees the terminator come out of the elevator is *perfect*.