Building a crystal clock source for a CPU used to be a bit of an effort but these days, there’s nothing to it. Even if your CPU or other device needs an external clock, you just slap in an inverter, a crystal, and two capacitors together, and you are done, right? Maybe not. [Dave Collins] got interested in the common circuit and pulled out his scope and an array of different kinds of inverters. He looked at inverters and NAND gates and a few common circuit configurations.
This is one of those things you just assume is of little importance, but it turns out your choice of circuit architecture and active device can have a big impact on the output. But who has time to do all the testing? Thanks to [Dave] you don’t have to.
Recently [Roberto Barrios] got his hands on a Rohde & Schwarz EB200 monitoring and surveillance receiver that, despite its late 90s vintage, was in mint condition. Aside from damage to the main dial, that is, which was very much broken. With no off-the-shelf replacement available in 2023, the obvious answer was to get a close-enough dial knob with the rough proportions and use a lathe to machine it into shape. Initially, [Roberto] had used some filler material to replace the front of the original knob that was missing, but this was a decidedly inferior tactile experience with questionable long-term reliability.
Dimensions of the Rhode & Schwarz EB200 dial knob. (Credit: Roberto Barrios)
The challenge in replacing the original knob with a proper replacement was in how the dial knob is mounted on the receiver, as an internally threaded shell that goes on the internal dial encoder assembly. With a lathe at his behest, taking an off-the-shelf dial knob that accepts a 6 mm shaft and turning it into a compatible knob was a straightforward affair. Removing the excess material and creating the internal 1 mm pitch thread allowed the newly made knob to fit on the receiver like an OEM part. The only niggle was having to remove 1.8 mm off the face of the brass body to get the knob to sit close to the front panel.
Unlike the old patched-up knob, this new one is fully out of metal and has the absolutely essential feature of the recessed area for easy fine-tuning. Although perhaps not the most exciting fix for old gear, it’s decidedly essential to keep it functional.
Have you ever wanted to be the best Super Mario Brothers speedrunner, but you just couldn’t do the frame-perfect inputs? Fear not, because [Gregory Strike] is here to save the day with his automatic NES controller!
In his previous video, [Greg] already made an automatic controller that plays a sequence of inputs at the perfect time, but it still failed some of the frame-perfect tricks. So what gives? Deviation in the timing of the NES itself gives, as he shows how the NES doesn’t sample inputs at exactly the same time every frame. To account for this, he used the latch signal, which starts the controller reading process as a time reference, and replaced his digital “mixtape” with a more time-flexible Arduino. After the modification, he shows it pulling off frame-perfect inputs every time he plays Super Mario Brothers.
But if you have a controller that can do frame-perfect inputs and it can be connected to a computer, you can connect the controller to the internet! That’s right, [Greg] created a Twitch bot that tells the Arduino exactly what inputs to send, which then relays it to the NES. It accepts simple sequences of inputs via chat, and you can try it out right now on [Greg]’s Twitch stream.
This project shows promising results, and we think it’s possible to do much more with its internet connection. We’re certainly looking forward to what [Greg] decides to make next.
[Matt Vella] has had a talking, non-posable skeleton knocking around for years. As cool as that sounds, [Matt] is really tired of its three stock phrases. Fast forward to this year — [Matt] got a posable skeleton and decided to go all out on this, the hackiest of all holidays. The result? Hack Skellington.
Between the eye socket-mounted camera, the speaker, and servos in the head, jaw, and one arm, Hack Skellington is decked out to scare trick-or-treaters (or anyone who gets close enough) in modern fashion. Thanks to ChatGPT and an AI-generated voice, Hack can recognize people and welcome them by name, look people in the eye, or simply move its arm when someone gets too close.
The brains of this operation is a Radxa Zero SBC programmed in Viam, though any SBC with Wi-Fi, GPIO, I²C, and USB should work just fine. [Matt] only spent about $150 total, half of which went to the skeleton itself. Be sure to check the spooky action out after the break.
You have until 9 AM PT on Tuesday, October 31st to enter the 2023 Halloween Hackfest. Procrastinators unite! Don’t want to animate a whole skeleton? Come to think of it, a severed, animated hand is even creepier, anyway.
“As California goes, so goes the nation.” That adage has been true on and off for the last 100 years or so, and it’s true again now that GM’s Cruise self-driving car unit has halted operations across the United States, just a couple of days after California’s DMV suspended its license to conduct driverless tests on state roadways. The nationwide shutdown of testing was undertaken voluntarily by the company and takes their sore beset self-driving taxi fleet off the road in Phoenix, Houston, Austin, Dallas, and Miami, in addition to the California ban, which seemed to be mainly happening in San Francisco. Cruise’s fleet has suffered all manner of indignities over the last few months, from vandalism to “coning” pranks to even being used as rolling hookup spots, and that’s not to mention all the trouble they caused by brigading to the same address or losing games of chicken with a semi and a firetruck. We’re not sure what to make of all this; despite our somewhat snarky commentary on the company’s woes, we take little pleasure in this development other than to the degree it probably increases roadway safety in the former test cities. We really do want to see self-driving cars succeed, at least for certain use cases, but it seems like this is a case of too much, too soon for the technology we currently have at our disposal.
We’ve previously reported from the UK about the Online Safety Bill, a piece of internet safety legislation that contains several concerning provisions relating to online privacy and encryption. UK laws enter the statutes by royal assent after being approved by Parliament, so with the signature of the King, it has now become the law of the land as the Online Safety Act 2023. Now that it’s beyond amendment, it’s time to take stock for a minute: what does it mean for internet users, both in the UK and beyond its shores? Continue reading “The UK Online Safety Bill Becomes Law, What Does It Mean?”→
DIY electric personal vehicles are a field where even hobbyists can meaningfully innovate, and that’s demonstrated by the Mega-Wheelie, a self-balancing one-wheeled skateboard constructed as an experiment in traversing off-road conditions.
[John Dingley] and [Nick Thatcher] have been building and testing self-balancing electric vehicles since 2008, with a beach being a common testing ground. They suspected that a larger wheel was the key to working better on rough ground and dry sand and tested this idea by creating a skateboard with a single wheel. A very big, very wide wheel, in fact.
The Mega-Wheelie houses a 24V LiFePO4 battery pack, 450 W gearmotor with chain and sprocket drive, SyRen motor controller from Dimension Engineering, Arduino microcontroller, and an inertial measurement unit to enable the self-balancing function. Steering is done by leaning, and the handheld controller is just a dead man’s switch that disables the vehicle if the person piloting it lets go.
Design-wise, a device like this has a few challenging constraints. A big wheel is essential for performance but takes up space that could otherwise be used for things like batteries. Also, the platform upon which the pilot stands needs to be as low to the ground as possible for maximum stability. Otherwise, it’s too easy to fall sideways. On the other hand, one must balance this against the need for sufficient ground clearance.
Beaches are rarely covered in perfectly smooth and firm sand, making them a good test area.
In the end, how well did it work? Well enough to warrant a future version, says [John]. We can’t wait to see what that looks like, considering their past 3000 W unicycle’s only limitation was “personal courage” and featured a slick mechanism that shifted the pilot’s weight subtly to aid steering. A video of the Mega-Wheelie (and a more recent unicycle design) is embedded just below the page break.
