Se Ao Menos Ele Tivesse Prestado Mais Atenção ás Aulas De Física.

Sewing Machines & Planned Obsolescence

I've got these two sewing machines, made about 100 years apart. An old treadle machine from around 1920-1930, that I pulled out of the trash on a rainy day, and a new Brother sewing machine from around 2020.

I've always known planned obsolescence was a thing, but I never knew just how insidious it was till I started looking at these two side by side.

I wasn't feeling hopeful at first that I'd actually be able to fix the old one, I found it in the trash at 2 am in a thunderstorm. It was rusty, dusty, soggy, squeaky, missing parts, and 100 years old.

How do you even find specialized parts 100 years later? Well, easily, it turns out. The manufacturers at the time didn't just make parts backwards compatible to be consistent across the years, but also interchangeable across brands! Imagine that today, being able to grab a part from an old iPhone to fix your Android.

Anyway, 6 months into having them both, I can confidently say that my busted up trash machine is far better than my new one, or any consumer-grade sewing machine on the market.

Old Machine Guts

The old machine? Can sew through a pile of leather thicker than my fingers like it's nothing. (it's actually terrifying and I treat it like a power tool - I'll never sew drunk on that thing because I'm genuinely afraid it'd sew through a finger!) At high speeds, it's well balanced and doesn't shake. The parts are all metal, attached by standard flathead screws, designed to be simple and strong, and easily reachable behind large access doors. The tools I need to work on it? A screwdriver and oil. Lost my screwdriver? That's OK, a knife works too.

New Machine Guts

The new machine's skipping stitches now that the plastic parts are starting to wear out. It's always throwing software errors, and it damn near shakes itself apart at top speed. Look at it's innards - I could barely fit a boriscope camera that's about as thick as spaghetti in there let alone my fingers. Very little is attached with standard screws.

And it's infuriating. I'm an engineer - there's no damn reason to make high-wear parts out of plastic. Or put them in places they can't be reached to replace. There's no reason to make your mechanism so unbalanced it's reaching the point of failure before reaching it's own design speed. (Oh yeah there is, it's corporate greed)

100 years, and your standard home sewing machine has gone from a beast of a machine that can be pulled out of the literal waterlogged trash and repaired - to a machine that eats itself if you sew anything but delicate fast-fashion fabrics that are also designed to fall apart in a few years.

Looking for something modern built to the standard that was set 100 years ago? I'd be looking at industrial machines that are going for thousands of dollars... Used on craigslist. I don't even want to know what they'd cost new.

We have the technology and knowledge to manufacture "old" sewing machines still. Hell, even better, sewing machines with the mechanical design quality of the old ones, but with more modern features. It would be so easy - at a technical level to start building things well again. Hell, it's easier to fabricate something sturdy than engineer something to fail at just the right time. (I have half a mind to see if any of my meche friends with machine shops want to help me fabricate an actually good modern machine lol)

We need to push for right-to-repair laws, and legislation against planned obsolescence. Because it's honestly shocking how corporate greed has downright sabotaged good design. They're selling us utter shit, and expecting us to come back for more every financial quarter? I'm over it.

E se o adversário chutar quando ele abaixar ?

💪

my trick for getting through grad school is learning to navigate the quadrants with all their nuances

Agradeço a todos que colaboraram com minhas 50 curtidas!

Brilhante

Tudo junto? Legal.

a collection of study tips

i’ve been really into browsing through other ppl’s blogs looking at study tips posts, reading through them to glean an idea of how other people make their study time more effective, and i wanted to combine them all in one place for easy referral so here goes ;;

what to do when you feel like you just can’t keep studying

how to feel good about yourself when school is kicking your ass

top tips for dealing with a bad grade or failing class

an overview of stephen covey’s prioritization matrix

a guide for the school year

how to make a stress-free exam study plan

college tips that actually help

quickfire study tips

tips for a more productive session

how i study

general study tips

more study tips

5 revision methods to try

tips for success

how to handle having too much to do

Hello beautiful. (via)

Antenas, vale a pena estudar elas.

Best Partner for Wireless Modules: A Comprehensive Antenna Selection Guide

n the field of wireless communication, antenna selection is crucial. It not only affects the coverage range and transmission quality of signals but also directly relates to the overall performance of the system. Among various wireless modules, finding the right antenna can maximize their potential, ensuring stable and efficient data transmission.

When designing wireless transceiver devices for RF systems, antenna design and selection are essential components. A high-quality antenna system can ensure optimal communication distances. Typically, the size of antennas of the same type is proportional to the wavelength of the RF signal; as signal strength increases, the number of required antennas also grows.

Antennae can be categorized as internal or external based on their installation location. Internal antennas are installed within the device, while external antennas are mounted outside.

In situations where space is limited or there are multiple frequency bands, antenna design becomes more complex. External antennas are usually standard products, allowing users to simply select the required frequency band without needing additional tuning, making them convenient and easy to use.

What are the main types of antennas?

External Antennas: These antennas can be classified into omnidirectional antennas and directional antennas based on the radiation pattern.

Internal Antennas: These antennas refer  to antennas that can be placed inside devices.

Omnidirectional Antennas: These antennas radiate signals uniformly in the horizontal plane, making them suitable for applications that require 360-degree coverage, such as home Wi-Fi routers and mobile devices.

Directional Antennas: These antennas have a high emission and reception strength in one or more specific directions, while the strength is minimal or zero in others. Directional antennas are primarily used to enhance signal strength and improve interference resistance.

PCB Antennas: These antennas are directly printed on the circuit board and are suitable for devices with limited space, commonly used in small wireless modules and IoT devices.

FPC Antennas: FPC antennas are flexible printed circuit antennas that are lightweight, efficient, and easy to integrate.

Concealed Antennas: Designed for aesthetic purposes, concealed antennas can be hidden within devices or disguised as other objects, making them suitable for applications where appearance is important without compromising signal quality.

Antenna Selection Guide

When selecting the appropriate antenna for a communication module, it's essential to first determine whether to use an internal or external antenna based on the module's structure.

External Antennas: These antennas offer high gain, are less affected by the environment, and can save development time, but they may take up space and impact the product's aesthetics.

Internal Antennas: These have relatively high gain and are installed within the device, maintaining a clean and appealing exterior.

 Sucker  Antennas: These provide high gain and are easy to install and secure.

Copper Rod  Sucker  Antennas: Made from large-diameter pure copper radiators, these are highly efficient with a wide bandwidth.

Rubber Rod Antennas: Offer moderate gain at a low cost.

Fiberglass Antennas: Suitable for harsh environments and ideal for long-distance signal

External Directional Antennas

Typically used in environments with long communication distances, small signal coverage areas, and high target density.

Panel Antennas have high efficiency, are compact, and easy to install, while considering the impact of gain and radiation area Yagi Antennas offer very high gain, are slightly larger, and have strong directionality, making them suitable for long-distance signal transmission; however, attention must be paid to the antenna's orientation during use

Internal Antenna Selection

Most internal antennas are affected by environmental factors and may require custom design or impedance matching

Spring Antennas are cost-effective but have low gain and narrow bandwidth, often requiring tuning for good matching when installed Ceramic Patch Antennas occupy minimal space and perform well, but have a narrow bandwidth

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