You’ve Got Mail: It All Depends On ZIP Code

Previously on You’ve Got Mail, we looked at a few services that were designed to speed up the mail at various points along the way. But these improvements were all taking place on the USPS’ side of the the fence. Was there anything the customer could be doing to help out?

A post card from my collection.

As it turns out, yes. And it was almost too late. Whereas you could once address a letter or postcard simply to “Fred Minke, Somerset, Wis.” and it would reach him, the volume of mail was getting completely out of hand with the rise of computers, automated billing, and advertising. Something was needed to improve routing and speed up delivery.

We all know enough about ZIP codes to use them, but where did they come from? How many types are out there? What do they even mean? Let’s find out.

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Screech Owl Is A Tribute To The Eowave Persephone

The Eowave Persephone was a beautiful thing—a monophonic ribbon synth capable of producing clean, smoothly varying tones. [Ben Glover] used to own a nice example that formerly belonged to Peter Christopherson, but lost it in the shifting sands of time. His solution was to build one of his own from scratch.

It’s a simple build, but the final result puts out a nice pleasant sound.

Known as the Screech Owl, the build is based around a custom shield designed to suit the Arduino Leonardo. The primary control interface is a Softpot 500 mm membrane potentiometer, layered up with a further thin film pressure sensor which provides aftertouch control. The Leonardo reads these sensors and synthesizes the appropriate frequencies in turn.

All the electronics is wrapped up inside a tidy laser-cut enclosure that roughly approximates the design of the original Eowave device. [Ben] noted the value of services like Fiverr and ChatGPT for helping him with the design, while he also enjoyed getting his first shield design professionally manufactured via JLCPCB.

It’s a tidy build, and in [Ben’s] capable hands, it sounds pretty good, too. We’ve seen some other great ribbon controlled synths before, too. Video after the break.

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Error-Correcting RAM On The Desktop

When running a server, especially one with mission-critical applications, it’s common practice to use error-correcting code (ECC) memory. As the name suggests, it uses an error-correcting algorithm to continually check for and fix certain errors in memory. We don’t often see these memory modules on the desktop for plenty of reasons, among which are increased cost and overhead and decreased performance for only marginal gains, but if your data is of upmost importance even when working on a desktop machine, it is possible to get these modules up and running in certain modern AMD computers.

Specifically, this feature was available on AMD Ryzen CPUs, but since the 7000 series with the AM5 socket launched, the feature wasn’t officially supported anymore. [Rain] decided to upgrade their computer anyway, but there were some rumors floating around the Internet that this feature might still be functional. An upgrade to the new motherboard’s UEFI was required, as well as some tweaks to the Linux kernel to make sure there was support for these memory modules. After probing the system’s behavior, it is verified that the ECC RAM is working and properly reporting errors to the operating system.

Reporting to the OS and enabling the correct modules is one thing, actually correcting an error was another. It turns out that introducing errors manually and letting the memory correct them is possible as well, and [Rain] was able to perform this check during this process as well. While ECC RAM may be considered overkill for most desktop users, it offers valuable data integrity for professional or work-related tasks. Just don’t use it for your Super Mario 64 speedruns.

Nifty MIG Welder Built From Scrap

A MIG welder is a great tool to have. With machine fed wire and gas protecting the arc, it can make it easy to weld well without requiring a lot of manual skill from the operator. [PROFESSOR PARDAL BRASIL] decided to build his own MIG welder using scrap parts, and it’s an inspiring bit of work.

The build is along the lines of so many YouTube contraptions, using bits and pieces thrown together in oddball ways. A windscreen wiper motor is used to create a wire feeder, with jammed-up ball bearings acting as rollers. Speed control of the wiper motor appears to be via a variable resistor created by moving two plates closer together in a bath of salt water. This enables the wire feed rate to be easily controlled, albeit in a wet and messy fashion. The build includes a device for producing carbon dioxide for use as shielding gas, too. This is achieved by mixing a solution of water and bicarbonate soda with vinegar, and then pumping the resulting carbon dioxide into an inner tube for storage. The power supply for actually creating an arc comes courtesy of car batteries.

The resulting welder is janky as all heck, but it does successfully weld some steel plates together. Job done, as they say. Video after the break.  Continue reading “Nifty MIG Welder Built From Scrap”

The Wirtz Pump Spins

Over the ages, a lot of human activity has been concerned about getting water from where we find it to where we want it. If you want to move water to a lower elevation, there’s no problem. But if you want to move water up, you need a pump. The ancients used what we call Archimedes’ screw to raise water. But a Wirtz pump as [Steve Mould] shows in the video below, is another kind of spiral pump that is also very old and uses the same basic principle as the screw pump.

In a way, the Wirtz is just an Archimedes’ screw in cross-section. Part of what makes it work, however, is air-locking. [Steve] made a small model but found it didn’t work exactly as he expected. Of course, investigating that led to some interesting observations.

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A Buzzing, Flashing Phone Ringer For The Elderly

For a lonely person, elderly or otherwise, the sound of a ringing phone can be music to the ears, unless of course it’s another spam call. But what good is a phone when you can’t hear it well enough to answer?

[Giovanni Aggiustatutto] was tasked with building an additional ringer for a set of cordless landline phones belonging to an elderly friend. Rather than try to intercept the signal, [Giovanni] chose to simply mic up the phone base that’s connected to the phone port on the router and send a signal over Wi-Fi to a second box which has a loud piezo buzzer and a handful of LEDs.

At the heart of this build is a pair of ESP8266 Wemos D1 minis and an Arduino sound sensor module inside a pair of really nice-looking 3D printed boxen that may or may not have been inspired by an IKEA air quality sensor. On the receiving side, a green LED indicates the system is working, and the red LEDs flash as soon as a call comes in.

All the code, schematics, and STL files are available for this build, and between the Instructable and the build video after the break, you should have no trouble replicating it for the hard-of-hearing in your life.

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Micromanipulator Touches The Tiny Things, Cheaply

Some things are small and fragile enough that they cannot be held or touched by even the steadiest of hands. Such cases call for a micromanipulator, and [BYU CMR]’s DIY micromanipulator design can be 3D printed and assembled with the help of some common hardware, and a little CA glue.

You may recall an ultra-tiny Nerf-like blaster recently; clearly such a tiny mechanical device cannot be handled directly, yet needed to be loaded and have its trigger pressed. A micromanipulator is exactly the tool for such a job. This design is in fact the very same one used to move and manipulate that tiny blaster at a microscopic level.

The design doesn’t include any end effectors — those depend on one’s application — but there is a mount point for them and the manipulator can effectively move it in X, Y, and Z axes by turning three different knobs. In addition, because the structural parts can be 3D printed and the hardware is just some common nuts and screws, it’s remarkably economical which is always a welcome thing for a workshop.