Life-Saving Surgery For A Telescopic Antenna

July 11, 2020 by Tom Nardi 19 Comments

Whether it was as an impulsive youth or an impatient adult, there’s probably few among us who haven’t broken a telescopic antenna or two over the years. It doesn’t take much to put a bend in the thin walled tubing, and after that, all bets are off. So [The Amateur Engineer] couldn’t really be too upset when his son snapped the antenna off the transmitter of an old RC truck. Instead, he decided to take it apart and see how it could be repaired.

Taking a thin screwdriver to the antenna’s bottom most segment, he was able to widen up the opening enough to remove the upper sections as well as recover the broken piece and copper locking plates. He cut out the damaged area and drilled new holes for the pins on the copper plates to fit into. Inserting the repaired section back into the lowest segment was no problem, but he says it took a little trial and error before he was able to roll the edge over enough to keep the antenna from falling apart.

Buying a replacement would certainly have been easier, but as the radios in our devices have moved into the higher frequencies, these collapsible antennas have become a bit harder to come by. Modern RC vehicles operate on 2.4 GHz, so they don’t need the long antennas that the older 27 MHz systems utilized. [The Amateur Engineer] did find a few direct replacements online, but none for a price he was willing to pay.

We might have used the broken transmitter as an excuse to switch the RC vehicle over to WiFi control, but we appreciate [The Amateur Engineer] showing how this type of antenna can be disassembled and repaired if necessary.

Hacked Case Fan Follows The Leader With IR Sensor

July 10, 2020 by Tom Nardi 22 Comments

Adding an additional fan to your PC is usually pretty straightforward, but as [Randy Elwin] found, this isn’t always the case with the newer Small Form Factor (SFF) machines. Not only was the standard 80 mm fan too large to fit inside of the case, but there wasn’t even a spot to plug it in. So he had to come up with his own way to power it up and control its speed.

Now if he only needed power, that wouldn’t have been a problem. You could certainly tap into one of the wires coming from the PSU and get 12 V to spin the fan. But that would mean it was running at max speed the whole time; fine in a pinch, but not exactly ideal for a daily driver.

Note the SATA connector pulled from a dead HDD.

To get speed control, [Randy] put together a little circuit using an ATtiny85, an IR LED, and a LTR-306 phototransistor. The optical components are used to detect the GPU fan’s current speed, which itself is controlled based on system temperature. Using the GPU fan RPM as an input, a lookup table on the microcontroller sets an appropriate speed for the 80 mm case fan.

One could argue that it would have been easier to connect a temperature sensor to the ATtiny85, but by synchronizing the case fan to the computer-controlled GPU fan, [Randy] is able to manually control them both from software if necessary. Rather than waiting on the case temperature to rise, he can peg the GPU fan and have the external fan speed up to match when the system is under heavy load.

You may think this is overkill for a simple case fan, but compared to some of the cooling hacks we’ve seen in the past, it’s pretty tame.

Steampunk Geiger Counter Is A Mix Of Art And Science

July 10, 2020 by Tom Nardi 11 Comments

It took nearly a year for [Chris Crocker-White] to assemble this glorious mahogany and brass Geiger counter, but we think you’ll agree with us that it was time well spent. From the servo-actuated counter to the Nixie tubes and LED faux-decatrons, this project is an absolute love letter to antiquated methods of displaying information. Although for good measure, the internal Raspberry Pi also pushes all the collected radiation data into the cloud.

[Chris] says the design of this radiation monitor was influenced by his interest in steampunk and personal experience working on actual steam engines, but more specifically, he also drew inspiration from a counter built by [Richard Mudhar].

Based on a design published in Maplin back in 1987, [Richard] included a physical counter and LED “dekatron” displays as an homage to a 1960s era counter he’d used back in his school days. [Chris] put a modern spin on the electronics and added the glowing display of real-time Counts Per Minute (CPM) as an extra bonus; because who doesn’t like some Nixies in their steampunk?

Internally, the pulses generated by a common Geiger counter board are picked up by some custom electronics to drive the servo and LEDs. Triggered by those same pulses, the Raspberry Pi 3A+ updates the Nixie display and pushes the data out to the cloud for analysis and graphing. Note that the J305β Geiger tube from the detector has been relocated to the outside of the machine, with two copper elbows used as connectors. This improves the sensitivity of the instrument, but perhaps even more importantly, looks awesome.

We’ve seen some very high-tech DIY radiation detection gear over the years, but these clever machines that add a bit of whimsy to the otherwise mildly terrifying process of ionizing radiation are always our favorite.

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3D Printing A Macro Pad, Switches And All

July 9, 2020 by Tom Nardi 15 Comments

Building a macro pad inside of a 3D printed enclosure is hardly news these days. Neither is adding 3D printed keycaps to the mix. But if you go as far as [James Stanley] has, and actually print the switches themselves, we’ve got to admit that’s another story entirely.

Now you might be wondering how [James] managed to print a mechanical keyboard switch that’s the size of your garden variety Cherry. Well, the simple answer is that he didn’t. While his printed switches have the same footprint as traditional switches, they are twice as tall.

The switches could probably made much smaller if it wasn’t for the printed spring, but using a “real” one would defeat the purpose. Though we do wonder if the mechanical design could be simplified by making it an optical switch.

But can printed switches really stand up to daily use? [James] wondered the same thing, so he built a testing rig that would hit the switches and count how many iterations before they stopped working. This testing seems to indicate that the keys will either fail quickly due to some mechanical defect, or last for hundreds of thousands of presses. So assuming you weed out the duds early, you should be in pretty good shape.

Naturally, there are a few bits of copper inside each printed switch to act as the actual contacts. But beyond that, all you need to build one of these printable pads yourself is a USB-HID capable microcontroller like the Arduino Pro Micro. If you used the ESP32, you could even make it Bluetooth.

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Synthesizer Gets An External Touch Screen

July 8, 2020 by Tom Nardi 3 Comments

Like other owners of the high-end Yamaha MODX, [sn00zerman] wasn’t happy with the synthesizer’s integrated touch screen. It’s a bit small, and not at a very good angle for viewing. So he made it his mission to find some way of adding a larger external touch screen without making any permanent modifications to the expensive instrument.

This might seem like a tall order, but he wasn’t starting from zero. It was already known that you could plug an external display into it if you used a USB to DVI/HDMI adapter; but without the touch overlay it wasn’t a particularly useful trick. He pondered adding an external connector for the device’s built-in touch screen overlay, but that broke his no modifications rule. Considering how much one of these things cost, we can’t blame him for not wanting to put a hole in the side.

Sometimes you just have to dig out the right parts.

So he started to look for a software solution to get him the rest of the way. Luckily the MODX runs Linux, and Yamaha has made good on their GPL responsibilities and released the source code for anyone who’s interested. While poking around, he figured out that the device uses tslib to talk to the touch screen, which [sn00zerman] had worked with on previous projects. He realized that the solution might be as simple as finding a USB touch screen controller that’s compatible with the version of tslib running on the MODX.

In the end, a trip through his parts bin uncovered a stand-alone touch screen controller that he knew from experience would work with the library. Sure enough, when plugged into the MODX, the OS accepted it as an input device. With the addition of a USB hub, he was able to combine this with an existing display and finally have a more comfortable user-interface for his synthesizer.

Now all he’s got to do is plug in a USB floppy drive, and he’ll have the ultimate Yamaha Beat Laboratory.

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Heater Joins The Internet Of Things With ESP32 Board

July 8, 2020 by Tom Nardi 15 Comments

The wood-burning heater [g3gg0] has at home works perfectly, except for one flaw: the pellet reservoir needs to be manually refilled every few days. Humans being notoriously unreliable creatures, this critical task is sometimes overlooked, which naturally leads to literally chilling results.

With automatic fill systems expensive and difficult to install, [g3gg0] wanted to find some kind of way for the heater to notify its caretakers about any potential fault conditions. Not just the fact that it was out of fuel (though that would naturally be the most common alert), but any other issue which would potentially keep the heater from doing it’s job. In short, the heater was going to get a one-way ticket to the Internet of Things.

As it turns out, this task was not quite as difficult as you might expect. The Windhager heater already had upgrade bays where the user could insert additional modules and sensors, as well as a rudimentary data bus over RS-485. All [g3gg0] had to do was tap into this bus, decode what the packets contained, and use the information to generate alerts over the network. The ESP32 was more than up to the task, it just needed a custom PCB and 3D printed enclosure that would allow it to slot into the heater like an official expansion module.

When an interesting message flashes across the bus, the ESP32 captures it and relays the appropriate message to an MQTT broker. From there, the automation possibilities are nearly endless. In this case, the heater’s status information is being visualized with tools like Grafana, and important alerts are sent out to mobile devices with PushingBox. With a setup like this, the Windhager will never go hungry again.

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Animatronic Nikola Tesla Sets The Record Straight

July 8, 2020 by Tom Nardi 18 Comments

While the Hackaday reader likely knows all about Nikola Tesla and his incredible body of work, the same can’t necessarily be said for the average passerby. Even a child can be counted on to know the names of Thomas Edison and Alexander Graham Bell, but as [Daniel Springwald] laments, the name Tesla is more often associated with the line of sleek electric cars than the brilliant Serbian inventor they were named for.

Hoping to level the playing field a bit, [Daniel] has come up with a way for the great man to plead his case. This custom designed robotic facsimile of the alternating current aficionado is able to speak about Tesla’s life and accomplishments in an interactive, if rather creepy, format.

There isn’t a lot of technical detail on this one yet, but what we can glean from the image gallery and video below is that there are an incredible number of OpenSCAD-designed 3D printed parts knocking around inside Mr. Tesla’s head. Add into the mix a healthy dose of springs, linkages, and servos, and you’re just a mustache short of a museum exhibit.

Most of the animatronic projects we’ve covered in the past have been based on animals, so it’s certainly interesting to see what goes into approximating human mannerisms mechanically. We’re not sure if this talking Tesla head will help educate the masses, but it’s certainly an impressive technical achievement.

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