Can you build a HF SSB radio transciever in one weekend, while on the road, at parts from a swap meet? I can, but apparently not without setting something on fire.
Of course the swap meet I’m referring to is Hamvention, and Hamvention 2016 is coming up fast. In a previous trip to Hamvention, Scott Pastor (KC8KBK) and I challenged ourselves to restore tube radio gear in a dodgy Dayton-area hotel room where we repaired a WW2 era BC-224 and a Halicrafters receiver, scrounging parts from the Hamfest.
Our 2014 adventures were so much fun that it drove us to create our own hacking challenge in 2015 to cobble together a <$100 HF SSB transceiver (made in the USA for extra budget pressure), an ad-hoc antenna system, put this on the air, and make an out-of-state contact before the end of Hamvention using only parts and gear found at Hamvention. There’s no time to study manuals, antennas, EM theory, or vacuum tube circuitry. All you have are your whits, some basic tools, and all the Waffle House you can eat. But you have one thing on your side, the world’s largest collection of surplus electronics and radio junk in one place at one time. Can it be done?
We posted about a 3D printer fire a while back. An attendee of the Midwest RepRap Fest had left his printer alone only to find its immolated remains on his return. In the spirit of open source, naturally, he shared his experience with the rest of us. It occurred to me that hackers are never powerless and there are active things to be done and avenues to explore.
An animation of a commercial fires suppression system, fire trace’s, operation. Firetrace‘s website has more.
There are really fantastic commercial fire extinguishing systems out there. One implementation, which is commonly deployed in cabinets and machining centers, is a plastic tube pressurized with an extinguishing agent by a connected tank. When a fire breaks out the tube melts at the hottest locations, automatically spraying the area with a suppressant. Variations of this involve a metal nozzle filled with a wax or plastic blended to melt at a certain temperature, much like the overhead fire sprinklers.
This system is also used inside engine compartments with success. For example, this item on amazon, is nothing but a pressurized plastic tube with a gauge on one end. Since the inside of an engine compartment can be treated as an enclosed space, very little fire suppressant is needed to extinguish an unexpected flame. It is important to note that this system works in a high temperature environment like an engine compartment, which bodes well for enclosed build envelopes on 3D printers.
BlazeCut Automatic Fire Suppression System 6′ TV200FA, Automotive Extinguisher Installed under Car Hood.
Another option is to construct a suppressant mine. A Japanese and a Thai company have both come out with a throwable fire extinguisher. In the Japanese device, the outside of the extinguisher is a breakable glass vial which shatters upon impact; releasing the agent. The Thai device looks like a volley ball, and releases the agent upon the application of heat. This device seems like a better candidate for 3D printing or home projects. Imagine a small rectangular pack with adhesive on one side that sits near the possible fire points of the printer, such as under the bed or above the nozzle. In the event of a fire, the casing will melt and the system will automatically deploy a spray of extinguishing agent.
Most of the chemicals used in these constructions are benign and readily available. High pressure tubing and waxes can all be purchased and the desired melt points can be aligned with their datasheets by need. Plastic sheets are not hard to procure. These offer a nice solution due to their entirely passive nature. They don’t need power to operate and rely entirely on the properties of the materials they are constructed out of.
There are other options in active systems. Hackaday readers suggested things such as flame sensors for adding automatic cut-offs in case of a fire. Thermal fuses can also be considered in some cases. There are other tricks too, which are less kosher but will work nonetheless. For example, placing a critical wire, fuse, or component in the likely path of a fire so that it is destroyed first, stopping the operation of the device quickly. These avenues should be explored. At minimum there should be at least one project that uses a Raspberry Pi and an Arduino to tweet that fire suppression failed and the house is on fire.
The Thai invention is a volleyball that melts upon contact with flame and releases a pressurized extinguishing agent.
Some of the big questions to ask are on the legal and ethical side. If someone started selling kits for a DIY fire suppression system and a fire ends up destroying someone’s property despite the device, who is responsible? Is it even safe to post instructions? What if a kit prematurely sets off and injures someone. I imagine a big part of the cost of these professional systems is some sort of liability insurance and certification. Still, putting a six hundred dollar fire suppression system on a six hundred dollar printer seems silly, and something is better than nothing.
Lastly, the comments directed a ton of flak towards the certification systems. There should be no reason that open source projects can’t produce their own specification for safety. An open source specification without an agency naturally couldn’t provide a legal defense against property damage, but a thought-out test program would provide piece of mind. For example, in the case of 3D printers, one could have a set of basic fail-safe tests. One example would be bringing the printer up to temperature and rapidly disconnecting the thermistor, does the printer erupt into fire? No? Good, it meets the spec. I wouldn’t mind knowing that the latest version of Marlin was tested on the popular boards and still met the community specification for fire safety.
As far as I can tell, there’s been very little work in open sourcing safety systems or in providing a testing framework for ensuring open hardware meets basic safety conditions. Many of you have experience with these systems. Some of you have gone through the entirely un-enjoyable process of getting a UL certification. What does Hackaday think?
[Jay] out of the River City Labs Hackerspace in Peoria, IL cleared out a jam in his printer. It’s an operation most of us who own a 3D printer have performed. He reassembled the nozzle, and in a moment forgot to tighten down the grub nut that holds the heater cartridge in place. He started a print, saw the first layer go down right, and left the house at 8:30 for work. When he came back from work at 10:30 he didn’t see the print he expected, but was instead greeted by acrid smoke and a burnt out printer.
The approximate start time of the fire can be guessed by the height of the print before failure.
As far as he can figure, some time at around the thirty minute mark the heater cartridge vibrated out of the block. The printer saw a drop in temperature and increased the power to the cartridge. Since the cartridge was now hanging in air and the thermistor that reads the temperature was still attached to the block, the printer kept sending power. Eventually the cartridge, without a place to dump the energy being fed to it, burst into flame. This resulted in the carnage pictured. Luckily the Zortrax is a solidly built full metal printer, so there wasn’t much fuel for the fire, but the damage is total and the fire could easily have spread.
Which brings us to the topics of discussion.
How much can we trust our own work? We all have our home-builds and once you’ve put a lot of work into a printer you want to see it print a lot of things. I regularly leave the house with a print running and have a few other home projects going 24/7. Am I being arrogant? Should I treat my home work with a lesser degree of trust than something built by a larger organization? Or is the chance about the same? Continue reading “Ask Hackaday MRRF Edition: 3D Printers Can Catch Fire”→
There is no denying that personal drones are in the public eye these days. Unfortunately they tend to receive more negative press than positive. This past weekend, there were news reports of a wildfire in California. Efforts to fight the fire were hampered when no less than five drones were spotted flying in the area. Some reports even stated that two of the drones followed the firefighting aircraft as they returned to local airports. This is the fourth time this month firefighting planes have been grounded due to unmanned aircraft in the area. It’s not a new problem either, I’ve subscribed to a google alert on the word “Drone” for over a year now, and it is rare for a week to go by without a hobby drone flying somewhere they shouldn’t.
The waters are muddied by the fact that mass media loves a good drone story. Any pilotless vehicle is now a drone, much to the chagrin of radio control enthusiasts who were flying before the Wright brothers. In this case there were two fields relatively close to the action – Victor Valley R/C Park, about 10 miles away, and the Cajun Pass slope flying field, which overlooks the section of I-15 that burned. There are claims on the various R/C forums and subreddits that it may have been members from either of those groups who were mistaken as drones in the flight path. Realistically though, Victor Valley is too far away. Furthermore, anyone at the Cajun pass flying site would have been fearing for their own safety. Access requires a drive through 3 miles of dirt road just to reach the site. Not a place you’d want to be trapped by a wildfire for sure. Who or whatever was flying that day is apparently lying low for the moment – but the problem persists.
Rules and Regulations
In the USA, the FAA rules are (finally) relatively clear for recreational drone operations. The layman version can be found on the knowbeforeyoufly.org website, which was put together by the Academy of Model Aeronautics (AMA), The Association for Unmanned Vehicle Systems International (AUVSI), and other groups in partnership with the FAA.
Accidents happen – but the awesome quotes you all sent in for Week 15 of the Caption CERN Contest were no accident. A huge thank you for our biggest week yet! The scientists in this week’s image are definitely cleaning up after some type of nasty accident. At first blush it looks like an electrical problem in the coils of what appears to be part of a beam line. With all that soot and radiation dangers to boot, only the photographer and the people in the image know for sure!
The Funnies:
“This is the second server these idiots have fried! What the hell’s a Hulu, and why are they trying to watch Gilligan’s Island with it?” Thanks to some unplanned quantum tunneling, Berners-Lee was even further ahead of his time than he thought” – [The Green Gentleman] (Two weeks in a row!)
“I found the bug. Who gets to tell Joe he’s sterile?”- [jonsmirl]
“‘I told the Captain that she couldn’t take any more’ – Scotty” – [md_reeves]
The winner for this week is [Mr. mmWave] himself, [Tony Long] with “Hardware Accelerator moto – Fail Fast, Fail Often. Also applies to Accelerator Hardware.” [Tony] will be debugging his next microwave mm band ham radio with a Logic Pirate From The Hackaday Store! Congratulations [Tony]!
Week 16: This is not your father’s POV Display!
Scientists at CERN have come up with some amazing science advancements. They’ve also needed ways to display the data they collect. This image may depict some incredible new way to display data collected from a high power physics experiment – or it could be a scientist’s project for the CERN science fair. We may never know.
The album is titled CHAMBRE A ETINCELLES DANS EXPO TECHNOL, which roughly translates to “Sparks in the technology expo room”. The lines traveling between the three horizontal display devices definitely appear to be aligned. Are they sparks of electricity? You tell us!
Week 14’s image may have had us at a loss for words, but it definitely didn’t slow down the intrepid caption contest entrants on Hackaday.io! Thanks to everyone who entered. We still have no idea what that device is, though we are sure that we wouldn’t want to be standing under it. Just look at those 4×4 sections of lumber holding everything up. What’s the French translation for “sketchy as hell”? The device definitely includes a pressure or vacuum vessel of some sort. Beyond that, your guess is as good as ours. We’ll keep an eye on CERN’s image discussion page in case an answer does pop up.
The Funnies:
“Damn it Athol, stop harping about protocol and hand me the duck tape. This is nuclear physics, not rocket science!” – [The Green Gentleman]
“This will mix a mean Margarita for the party tomorrow, I promise you!.”- [Mats L]
“To long have we tried to smash particles, now we will blend them.” – [paul]
The winner for this week is [LongHairedHacker] with: “After weeks of complicated assembly the team finally found out that the IKEA Årc, was in fact not a fusion reactor. It did make a hell of an espresso though.”
Accidents happen! When you’re working on the bleeding edge of science and technology, things don’t always go as planned. In this image, we’re looking at what appears to be the result of some sort of failure. We’re not sure what the piece of equipment was, but “was” is the proper term – as it’s now charred to a crisp.
The two scientists investigating the damage don’t seem to be worried about the radiation warning posted on the end of the machine’s aperture. Hopefully they know what they’re doing!
[Pat] was looking for a way to wirelessly control his Fire TV unit. He could have just went with one of many possible consumer products, but he decided to take it a step further. He modified a unit to fit inside of an original SNES controller. All of the buttons are functional, and the controller even features a wireless charger.
[Pat] started out with a Bluetooth video game controller marketed more playing video games on tablets. The original controller looked sort of like an XBox controller in shape. [Pat] tore this controller open and managed to stuff the guts into an original SNES controller. He didn’t even have to remove the original SNES PCB. [Pat] mentions that it was rather tedious to rewire all of the buttons from the original controller, but in the end it wasn’t too difficult. The only externally visible modification to the original controller is a small hole that was made for a power button.
In order to make this unit completely wireless, [Pat] also installed a Qi wireless charging module. Now, placing the controller on a charging pad will charge up the small LiPo battery in just about 45 minutes. This controller would be the perfect addition to a RetroPi or other similar project. If you’re not into Bluetooth, you can try using a Logitech receiver instead. Continue reading “SNES Controller Modified To Be Completely Wireless”→
There is no denying that personal drones are in the public eye these days. Unfortunately they tend to receive more negative press than positive. This past weekend, there were news reports of a wildfire in California. 
Last week’s prize was a 
