Author: Bryan Cockfield

1546 Articles

Retro Computer Goes Back To The 1950s

December 6, 2024 by 24 Comments

When thinking of retrocomputing, many of us will imagine machines such as the Commodore 64 or Apple II. These computers were very popular and have plenty of parts and documentation available. Fewer will go back to the Intel 8008 or even 4004 era which were the first integrated circuit chips commercially available. But before even those transistor-based computers is a retrocomputing era rarely touched on: the era of programmable vacuum tube machines. [Mike] has gone back to the 1950s with this computer which uses vacuum tubes instead of transistors.

The computer has an eight-bit architecture and features most of the components of any modern transistor-based computer of similar computational ability. Memory, I/O, an arithmetic logic unit including a carry bit that allows it to do 16-bit arithmetic, are all implemented using 6N3P dual triode tubes that date to the 50s and 60s and would have been used in similar computers like the IBM 700. All of this drives a flight simulator program or a Fibonacci number generator, demonstrating its general purpose computing capabilities.

Of course, tubes were generally phased out in favor of transistors largely due to their power and space requirements; [Mike] needs a stepladder to maintain this computer as well as around ten minutes each time he starts it up to allow the tubes to warm up, with each module needing over three amps of current each. It’s a hugely impressive build and we’d recommend checking out the video linked below to get more details on its operation. If you’re looking for something a little more accessible to get into the world of vacuum tubes, this single-board tube computer fits the bill.

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Building Experience And Circuits For Lithium Capacitors

December 2, 2024 by 22 Comments

For the cautious, a good piece of advice is to always wait to buy a new product until after the first model year, whether its cars or consumer electronics or any other major purchase. This gives the manufacturer a year to iron out the kinks and get everything ship shape the second time around. But not everyone is willing to wait on new tech. [Berto] has been interested in lithium capacitors, a fairly new type of super capacitor, and being unwilling to wait on support circuitry schematics to magically show up on the Internet he set about making his own.

The circuit he’s building here is a solar charger for the super capacitor. Being a fairly small device there’s not a lot of current, voltage, or energy, but these are different enough from other types of energy storage devices that it was worth taking a close look and designing something custom. An HT7533 is used for voltage regulation with a Schottky diode preventing return current to the solar cell, and a DW01 circuit is used to make sure that the capacitor doesn’t overcharge.

While the DW01 is made specifically for lithium ion batteries, [Berto] found that it was fairly suitable for this new type of capacitor as well. The capacitor itself is suited for many low-power, embedded applications where a battery might add complexity. Capacitors like this can charge much more rapidly and behave generally more linearly than their chemical cousins, and they aren’t limited to small applications either. For example, this RC plane was converted to run with super capacitors.

8-Bit Computers Crunch Advanced Scientific Computations

December 1, 2024 by 37 Comments

Although largely relegated to retrocomputing enthusiasts and embedded systems or microcontrollers now, there was a time when there were no other computers available other than those with 8-bit processors. The late 70s and early 80s would have seen computers with processors like the Motorola 6800 or Intel 8080 as the top-of-the-line equipment and, while underpowered by modern standards, these machines can do quite a bit of useful work even today. Mathematician [Jean Michel Sellier] wanted to demonstrate this so he set up a Commodore 64 to study some concepts like simulating a quantum computer.

The computer programs he’s written to do this work are in BASIC, a common high-level language of the era designed for ease of use. To simulate the quantum computer he sets up a matrix-vector multiplication but simplifies it using conditional logic. Everything is shown using the LIST command so those with access to older hardware like this can follow along. From there this quantum computer even goes as far as demonstrating a quantum full adder.

There are a number of other videos on other topics available as well. For example, there’s an AmigaBasic program that simulates quantum wave packets and a QBasic program that helps visualize the statistical likelihood of finding an electron at various locations around a hydrogen nucleus. While not likely to displace any supercomputing platforms anytime soon, it’s a good look at how you don’t need a lot of computing power in all situations. And, if you need a refresher on some of these concepts, there’s an overview on how modern quantum computers work here.

Pushing 802.11ah To The Extreme With Drones

December 1, 2024 by 20 Comments

It might come as a surprise to some that IEEE, the Institute for Electrical and Electronics Engineers, does more than send out mailers asking people to renew their memberships. In fact, they also maintain various electrical standards across a wide range of disciplines, but perhaps the one most of us interact with the most is the 802.11 standard which outlines WiFi. There have been many revisions over the years to improve throughput but the 802.11ah standard actually looks at decreasing throughput in favor of extremely increased range. Just how far you can communicate using this standard seems to depend on how many drones you have.

802.11ah, otherwise known as Wi-Fi HaLow, operates in the sub-gigahertz range which is part of why it has the capability of operating over longer distances. But [Aaron] is extending that distance even further by adding a pair of T-Halow devices, one in client mode and the other in AP (access point) mode, on a drone. The signal then hops from one laptop to a drone, then out to another drone with a similar setup, and then finally down to a second laptop. In theory this “Dragon Bridge” could allow devices to communicate as far as the drone bridge will allow, and indeed [Aaron] has plans for future revisions to include more powerful hardware which will allow even greater distances to be reached.

While there were a few bugs to work out initially, eventually he was able to get almost two kilometers of distance across six devices and two drones. Something like this might be useful for a distributed network of IoT devices that are just outside the range of a normal access point. The Dragon Bridge borrowed its name from DragonOS, a Linux distribution built by [Aaron] with a wide assortment of software-defined radio tools available out of the box. He’s even put in on the Steam Deck to test out long-distance WiFi.

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Fully Submerge This Modernized PH Sensor

November 29, 2024 by 18 Comments

There’s a school of thought that says you shouldn’t mess around with a solution that’s already working, but that’s never seemed to stop anyone in this community. When [Skye] was looking at the current state of connected pH meters they realized there was incredible room for improvement.

Called the Nectar Monitor, this pH meter is a more modern take on what is currently offered in this space. Open source and based on the ESP32, it’s accessible to most people with a soldering iron, fits into a standard project box, and includes other modern features like USB and WiFi connectivity. It can even measure conductivity and temperature. But the main improvement here is that unlike other monitors that can only be submerged temporarily, this one is designed to be under water for long time periods thanks to a specially designed probe and electrical isolation.

This design makes it an appealing choice for people with aquariums, hydroponic farms, or any other situation where constant monitoring of pH is extremely important to maintaining a balanced system. We’ve seen some unique takes on hydroponics before especially, including this build that moves the plants instead of the nutrient solution and this fully automated indoor garden.

A Robot Meant For Humans

November 26, 2024 by 11 Comments

Although humanity was hoping for a more optimistic robotic future in the post-war era, with media reflecting that sentiment like The Jetsons or Lost in Space, we seem to have shifted our collective consciousness (for good reasons) to a more Black Mirror/Terminator future as real-world companies like Boston Dynamics are actually building these styles of machines instead of helpful Rosies. But this future isn’t guaranteed, and a PhD researcher is hoping to claim back a more hopeful outlook with a robot called Blossom which is specifically built to investigate how humans interact with robots.

For a platform this robot is not too complex, consisting of an accessible frame that can be laser-cut from wood with only a few moving parts controlled by servos. The robot is not too large, either, and can be set on a desk to be used as a telepresence robot. But Blossom’s creator [Michael] wanted this to help understand how humans interact with robots so the latest version is outfitted not only with a large language model with text-to-speech capabilities, but also with a compelling backstory, lore, and a voice derived from Animal Crossing that’s neither human nor recognizable synthetic robot, all in an effort to make the device more approachable.

To that end, [Michael] set the robot up at a Maker Faire to see what sorts of interactions Blossom would have with passers by, and while most were interested in the web-based control system for the robot a few others came by and had conversations with it. It’s certainly an interesting project and reminds us a bit of this other piece of research from MIT that looked at how humans and robots can work productively alongside one another.

Alternatives Don’t Need To Be Bashed

November 26, 2024 by 20 Comments

By default, bash is the most popular command language simply because it’s included in most *nix operating systems. Additionally, people don’t tend to spend a lot of time thinking about whatever their computer uses for scripting as they might for other pieces of software like a word processor or browser. If you are so inclined to take a closer look at this tool that’s often taken for granted, there are a number of alternatives to bash and [monzool] wanted to investigate them closely.

Unlike other similar documentation that [monzool] has come across where the writers didn’t actually use the scripting languages being investigated, [monzool] is planning to use each of these and accomplish specific objectives. This will allow them to get a feel for the languages and whether or not they are acceptable alternatives for bash. Moving through directories, passing commands back and forth, manipulating strings, searching for files, and manipulating the terminal display settings are all included in this task list. A few languages are tossed out before initial testing even begins for not meeting certain specific requirements. One example is not being particularly useful in [monzool]’s preferred embedded environments, but even so there are enough bash alternatives to test out ten separate languages.

Unfortunately, at the end of the day none of the ten selected would make a true replacement for bash, at least for [monzool]’s use case, but there were a few standouts nonetheless. Nutshell was interesting for being a more modern, advanced system and [monzool] found Janet to be a fun and interesting project but had limitations with cross-compiling. All in all though this seemed to be an enjoyable experience that we’d recommend if you actually want to get into the weeds on what scripting languages are actually capable of. Another interesting one we featured a while back attempts to perform as a shell and a programming language simultaneously.