This is an overview of a 500,000 Watt radio transmitter site. It’s one of the slides shared in a guided video tour of the transmitter’s hardware. The radio station — whose call sign was WLW — called itself the Nation’s Station because of its ability to reach so much of the country.
It operated at the 500 kW level starting back in the 1930’s. The technology at the time meant that there were a lot of challenges involved with transmitting at this level of power. It took 750 kW input to achieve the 500 kW output. To reach that the station had a set of AC motors in the basement generating the 4500 Amps at 33 Volts DC
needed to power the transmitter to heat each filament. Obviously there was a lot of heat generated at the same time. The system was water-cooled. An elaborate network of Pyrex pipes carried distilled water to and from the tubes to handle the heat dissipation.
The video tour lasts about thirty minutes. It’s just packed with interesting tidbits from the experts leading the tour so add it to your watch list for some geeky entertainment over the weekend.
Continue reading “Retrotechtacular: A tour of WLW, a 500,000 Watt radio transmitter”
There’s still quite a bit of machining that goes into a CNC mill build of this size. But using 80/20 brand extruded rail optimizes most of the build process into tasks manageable by the average basement hacker. That’s not to say that we think [Jim] is average. He took this mill from start to finish in just two weeks.
He picked up the set of three ball screws on eBay for $180. Two of them drive the X axis with the third moving the cutter assembly along the Y axis. The X axis travels along a set of precision rails instead of precision rods. He machined his own mounting plates to which those are attached. For now he’s not running the motors at full speed because the vibration starts to make the table shake. He may end up bolting the base to the floor once all is said and done.
We see this extruded rail used all over the place. We could highlight some other mill builds or 3d printers, but instead we think you’ll enjoy an extruded rail robotic bass guitar.
Oh, one last thing. We’re not against a bit of pandering. Below you can see the mill cutting out the Hackaday logo:
Continue reading “CNC router built with 80/20 rail”
[MacGyver] [Lou Wozniak] is on a mission to build an internal combustion engine using only hardware store parts. What you see above is his third attempt at it. Depending on your hardware store this may have ventured outside of what they sell because [Lou] switched over to using gasoline. But the first two attempts were powered by a propane torch fuel canister.
Unfortunately it still isn’t running. But the demo below makes us think that he’s really close. Timing is always touchy and that seems to be what is causing the problems. He makes use of a lot of plumbing fixtures. At the right you can see the parts (including a peanut butter jar) which make his carburetor with a valve pointing straight up as the choke. The fuel and air mixture moves down through the pipe to the cylinder and valve assembly where it is ignited by the black grill igniter module. His custom cut plywood gear moves with the fly-wheel. It triggers his improvised spark plug by using a bit of wire to pull on the leaf switch.
We feel like he’s so close to getting this up and running. If you have any advice on where he might be going wrong [Lou] welcomes your input.
Continue reading “Building an internal combustion engine from hardware store parts”
Just about every engineer needs to take a drawing class, but until now we surprisingly haven’t seen electronics thrown into rulers, t-squares, and lead holders. [Anirudh] decided to change that with Glassified. It’s a transparent display embedded in a ruler that is able to capture hand drawn lines. These physical lines can be interacted with or measured, turning a ruler into a bridge between a paper drawing and a digital environment.
For the display, [Anirudh] mounted a transparent TOLED display with a digitizer input into a ruler. The digitizer captures the pen strokes underneath the ruler, and is able to interact with the physical lines, either to calculate the length and angle of lines, or just to bounce a digital ball inside a hand-drawn polygon.
There’s no word on how this display is being driven, or what kind of code is running on it. [Anirudh] said he will have some schematics and code available up on his website soon (it’s a 404 right now).
This one’s a treasure trove of CAN bus hacks that will scare the crap out of an unsuspecting driver — or worse. [Charlie Miller] and [Chris Valasek] are getting ready to present their findings, which were underwritten by DARPA, at this year’s Defcon. They gave a Forbes reporter a turn in the driver’s seat in order to show off.
You’ve got to see the video on this one. We haven’t had this much fun looking at potentially deadly car hacking since Waterloo Labs decided to go surfing on an Olds. The hacks shown off start as seemingly innocent data tweaks, like misrepresenting your fuel level or displaying 199 mph on the speedometer while the car is standing still. But things start to get interesting when they take that speed readout from 199 down to zero instantly, which has the effect of telling the car you’ve been in a crash (don’t worry, the airbags don’t fire). Other devilish tricks include yanking the steering wheel to one side by issuing a command telling the car to park itself when driving down the road. Worst of all is the ability to disable the brakes while the vehicle is in motion. Oh the pedal still moves, but the brake calipers don’t respond.
The purpose of the work is to highlight areas where auto manufacturers need to tighten up security. It certainly gives us an idea of what we’ll see in the next Bond film.
Continue reading “Defcon presenters preview hack that takes Prius out of driver’s control”
Some thought the first artificial intelligence would come about as an accident, others as a war machine that decides the only way to protect humans is to kill them all. It turns out both these ideas were wrong. The first AI is apparently a teddy bear, available on Kickstarter for $60.
The Supertoy Kickstarter is selling a mechatronic teddy bear with motors, speakers, and enough electronics to connect to a cell phone. After plugging your cell phone and stuffing it in Teddy’s thorax, the bear comes alive with an intelligence all his own and a voice seemingly lifted from [Peter Griffin].
Needless to say, we’re just a bit skeptical that Teddy here can perform as demonstrated in the Kickstarter video. While the team behind Teddy has developed a successful talking chatbot before, the video makes this tech seem too good. Even the voice sounds like a real person with a microphone, and not like a clunky GPS personality.
Feel free to speculate in the comments on how good this tech can possibly be.
The two circular displays seen above are Dekatrons built into an optical drive enclosure. [Matt Sylvester] picked up a couple of different types of these tubes on eBay. He etched his own driver, and was able to control them with an Arduino. After a few months went by he decided to revisit the project to see if it would work as a CPU and RAM usage meter.
These tubes need high voltage to get the neon display glowing brightly. This raised some concerns about having those voltage levels inside of his PC, as well as the noise which may be introduced by the supply. To deal with those issues [Matt] gutted an old optical drive, using its case to physically isolate the circuitry, and some optoisolators to protect the logic connections. His driver board uses an ATmega328 running the Arduino bootloader. It connects to the PC using an FTDI USB to Serial cable. This makes it a snap to push the performance data to the display. It also has the side benefit of allowing him to reprogram the chip without opening the case.
If you can’t find one of these tubes for your own project consider faking it.
Continue reading “Drive bay form factor dual Dekatron readouts for RAM and CPU usage”