Retrotechtacular: The J-57 Afterburner Engine

The J-57 afterburner engine appeared in many airplanes of notable make, including the F-101, -102, and -103. This USAF training film shows the parts of the J-57, explains the complex process by which the engine produces thrust, and describes some maintenance and troubleshooting procedures.

The name of this game is high performance. Precision thrust requires careful rigging of the engine’s fuel control linkage through a process called trimming. Here, the engine fuel control is adjusted with regard to several different RPM readings as prescribed in the manual.

One of the worst things that can happen to a J-57 is known as overtemping. This refers to high EGT, or exhaust gas temperature. If EGT is too high, the air-fuel ratio is not ideal. Troubleshooting a case of high EGT should begin with a check of the lines and the anti-icing valve. If the lines are good and the valve is closed, the instruments should be checked for accuracy. If they’re okay, then it’s time for a pre-trimming inspection.

In addition to EGT, engine performance is judged by RPM and PP7, the turbine discharge pressure. If RPM and PP7 are within spec and the EGT is still high, the engine must be pulled. It should be inspected for leaks and hot spots, and the seals should be examined thoroughly for cracks and burns. The cause for high EGT may be just one thing, or it could be several small problems. This film encourages the user to RTFM, which we think is great advice in general.

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New Part Day: The ESP8266 Killer

Around this time last year we first heard of the ESP8266 WiFi module. It’s still a great little module, providing WiFi connectivity for all those Internet of Things things at a price point of just $5. It’s an attractive price for a great module with a huge community pumping out a lot of projects for the platform.

Now there’s a new kid on the block. It’s called the EMW3165, and like the ESP it provides WiFi connectivity for a bunch of wireless projects. It’s much, much more capable with an STM32F4 ARM Coretex M4 microcontroller, a ‘self hosted’ networking library, more RAM, more Flash, and more GPIOs. How much, you’re probably asking yourself. It’s a dollar more than the ESP8266.

The datasheet for the module goes over all the gritty details. While this chip has 3.6V I/Os, there are some 5V tolerant pins – a boon for the Arduino crowd. It’s also surprisingly low power for something that connects to an 802.11n network. The real bonus here is the STM32F4 core – that’s a very, very powerful microcontroller, and if you want a 2-component WiFi webcam build, this is the part you should use. There will be a lot of interesting builds using this part. It’s also passed FCC certification. Very cool.

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Hackaday Links: July 12, 2015

Adafruit is working on a series of videos that’s basically Sesame Street for electronics. G is for Ground is out, where [Adabot] discovers pipes and lightning rods are connected to ground. Oh, the rhyming. Here’s the rest of the videos so far. We can’t wait for ‘Q is for Reactive Power’.

Think you’re good enough to build an airlock 70 cubic meters in volume that can cycle once every thirty seconds? How about building a 500 mile long steel tube with zero expansion joints across active fault lines? Can you stop a 3 ton vehicle traveling at 700 miles per hour in fifteen seconds? These are the near-impossible engineering challenges demanded of the hyperloop. The fact that no company will pay for this R&D should tell you something, but that doesn’t mean you still can’t contribute.

Calling everyone that isn’t from away. [Paul] lives near Augusta, Maine and can’t find a hackerspace. Augusta is the capital of the state, so there should be a hackerspace nearby. If you’re in the area, go leave a message on his profile.

Last week we found memristors you can buy. A few years ago, [Nyle] found them while hiking. They were crudded up shell casings, and experiments with sulfur and copper produced a memristor-like trace on a curve tracer.

Need a way to organize resistors? Use plastic bags that are the same size as trading cards.

The Arduino is too easy. It must be packaged into a format that is impossible to breadboard. It should be shaped like a banana. Open source? Don’t need that. The pins are incorrectly labelled, and will be different between manufacturing runs.

3D Printering: The Makerbot Class Action Suit

Since the 5th generation of Makerbot 3D printers were released at CES in 2014, there has been an avalanche of complaints about the smart extruder in these printers. Clogs were common, and the recommended fix was to simply replace the extruder. The smart extruder is a $175 part, and the mean time before failure is somewhere between 200 and 500 hours. With these smart extruders, you’re looking at a new extruder every dozen prints or so. Combine this with Makerbot’s abdication of open source values, and it’s easy to see why no one in the know would buy a Makerbot.

The performance of the 5th gen Makerbots is also reflected in the Stratasys stock price. The stock has tanked, from a high of $130.83 in early 2014 to a low of $31.88 a few days ago. This has investors calling for blood, and now there’s a class action suit claiming Stratasys violated securities laws. The court docs found by the folks at Adafruit allege Stratasys rushed the 5th gen Makerbots into production resulting in an avalanche of negative feedback, warranty claims, returns, and misled investors until the stock collapsed when the market was made aware of these issues.

The court documents allege Stratasys and Makerbot touted the incredible ease of use and ‘unmatched’ quality of the 5th generation of Makerbots, while former Makerbot employees confirmed known issues with the smart extruder. The 5th gen Makerbots were rushed into production without proper testing for performance and reliability and no standardized testing and validation program. In short, Makerbot itself didn’t know how bad the smart extruder was, but shipped the product anyway. This in turn hurt sales, with one sales executive leaving the company as he “did not want to sell the 5th generation printers after learning about the defect issues because he has a ‘conscience’.”

Despite this, those in charge at Makerbot and Stratasys continued to make misleading  positive claims about the reliability of their printers and how the printers were received by the market. This is the crux of the lawsuit, and something that points to an artificially inflated stock value.

The plaintiffs for this lawsuit are limited to Stratasys stock holders, and anyone out there who only owns a 5th gen Makerbot will sadly be ignored in this lawsuit. Still, if the claims of this lawsuit are true, Stratasys and Makerbot are in for a world of hurt; this is an alleged violation of federal securities laws. demanding a jury trial. Popcorn abounds, and as always, [Zach] and [Adam] came out ahead.

Hackaday Retro Edition: Androids And Amigas

Tiny ARM boards are everywhere, and if the Raspberry Pi is any indication, they’re mostly used for emulating old consoles and computers. With only a $30 single board computer, it’s easy to emulate an SNES, Apple II, C64, or any of the other piece of classic 80s or 90s hardware.

Understandably, there will eventually be a few projects and products that hope to capitalize on this retro trend. Few of them will go through the rigamarole of actually licensing the relevant IP. The Armiga is one of these projects. It’s an emulated Amiga 500 with 1MB of RAM packaged in what looks like a 3.5″ external floppy drive.

Inside this tiny little box is a dual core ARM for Amiga emulation. For the most part, this is just a basic Android system, but the real selling point of this system is the Armiga Project software. This is a full emulator and game browser that also includes a legal (!) copy of Kickstart 1.3. The ‘upscale’ version of the Armiga also includes a floppy disk controller and drive, should you ever want to dump all those old floppies sitting around in your attic.

This isn’t the first time we’ve heard about the Armiga. It was a crowdfunding campaign a year ago that was unsuccessful for reasons we can’t comprehend. The creators of the Armiga have forged on, and now these tiny little boxes of guru meditation have started shipping. The Beta units have sold out and there’s a waiting list for more.

Hacklet 55 – Home Automation Projects

Home automation – the idea of a smart home that monitors and controls the inside environment, takes commands from occupants, and generally makes living easier. Hackers, makers, and engineers have been building their own vision of the smart home for decades. Thanks to cell phones and the revolution of the “internet of things”, home automation is now in the public eye. The hackers haven’t stopped though. They’re still building dreams, one circuit and one line of code at a time. This week’s Hacklet is dedicated to some of the best home automation projects on Hackaday.io!

jarvisWe start at the top – [IamTeknik’s] Project Jarvis has been in the top five skulled and viewed projects on Hackaday.io for as long as we’ve been keeping records. Just like the fictional Tony Stark design which inspired its name, Jarvis is based on artificial intelligence. [IamTeknik] has created a system using the BeagleBone Black running his own custom software. He’s also creating Jarvis from the ground up – even the relay modules have been designed and built by [IamTeknik]. So far Jarvis has a great 3D printed door lock unit, and a really nice wall mounted tablet. We’re watching to see what modules [IamTeknik] adds next!

 

hcs[Morrisonpiano] is no home automation noob. He’s been running his own system for two decades. HCS_IV Home Automation System is a project to update his HCS_C home automation system. For the uninitiated, the original HCS was created by [Steve Ciarcia] of Byte and Circuit Cellar fame. There have been several generations of the hardware and software since then, with plenty hackers adding their own custom features. [Morrisonpiano] is updating his system with an NXP Arm Cortex M4 CPU, three big Altera Cyclone FPGAs, and plenty of flash storage. Why use a FPGA on a home automation system? I/O of course! HCS uses a ton of I/O. There are 16 RS485 ports and 10 RS232 serial ports. Going with an FPGA makes things flexible as well. Want to add CAN bus? Just drop in some CAN HDL code and you’re golden!

 

[Sswitchteven] is giving the smart home more senses with Squirco Smart Home System – Sensor Network. Rather than just have a temperature sensor at the thermostat, or a motion detector in the front foyer, [Steven] wants a network of unobtrusive sensors to blanket the home. He’s doing this by replacing the common light switch with a smart module that has sensors for temperature, humidity, and human presence. [Steven] has spent quite a bit of time researching and experimenting microwave tomography as a means to detect humans. Going with microwaves means no obvious PIR windows.

 

bbb-haFinally, we have [Ansaf Ahmad] with BeagleBone Black Home Automation. The idea for this project came from a calculus class on optimization. [Ansaf] is putting mathematical theorems to use in the real world by monitoring usage patterns and current demands of a device. With that data, he can optimize the usage to make things greener. So far, [Ansaf] has been experimenting with a lamp. The system has a web front end which uses PHP. The GPIO pins on the board are controlled using Python and Flask. As an early project, BeagleBone Home Automation is doing great – it’s already earned [Ansaf] high grades in his computer engineering class!

If you want more smart home goodness, check out our updated home automation projects list! Did I miss your project? Don’t be shy, just drop me a message on Hackaday.io. That’s it for this week’s Hacklet, As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

CAPTION CERN CONTEST – Saying Goodbye To An Old Friend

The tangled web woven by Week 22 of the Caption CERN Contest has come to a close. It’s been another bumper week with 112 comments. Thank you to everyone who submitted a caption! We realize it may have been hard for some of the network engineers out there to type through their tears, but thank you for persevering! While we don’t know exactly what these two CERN scientists were wiring up, [rwells97] did figure out that the scope in the image is most likely a Tektronix 545/A, which was a popular scope back in the late 1950s and early 1960s. The weight on a beast like that was around 70 lbs!

The Funnies:

  • “Dude, this one’s full of wires too! Every single one of these is full of wires! Why would anyone need so many wires? What in the name of God were they DOING down here?” – [The Green Gentleman]
  • “Getting to blinky” required a whole lot more work then the engineers realized…” – [Kieran Paulger]
  • “I think I lost an electron back here, Bob. I’m positive.” – [Christine Hampton]

This week’s winner is [alan] with “Daft Punk was actually two of CERN’s best acoustics researchers prior to forming the band. Here they are after hours working on the track that would later be named ‘Da Funk'”. [Alan] is a Computer Science PhD candidate with focus on computational biology, specifically population genomics. Hopefully he has some hardware in the mix somewhere, because we’re sending him a Stickvise from The Hackaday Store!

Week 23

cern-23-smSomething a bit different this week. CERN is probably best known for the various particle accelerators they’ve had over the years. One of the first units was synchrocyclotron SC-1, which operated from 1957 to 1974. According to the album page on CERN’s servers, SC-1’s last day of operation was celebrated with a funeral procession. Scientists, and staff walked the grounds with flowers, top hats, and even a shrouded coffin. We can all related to decommissioning a well-worn piece of equipment. Be it a computer, a machine tool, or even a synchrocyclotron, there are always the mixed feelings of thanks that it did a good job, and relief that it will no longer need to be maintained.

Even though we have a pretty good idea of what’s going on in this image, we’re going to caption it anyway! Give us your best captions of what you think is really going on here! This week’s prize is a LightBlue Bean from The Hackaday Store. Add your humorous caption as a comment to this project log. Make sure you’re commenting on the contest log, not on the this post. As always, if you actually have information about the image or the people in it, let CERN know on the original image discussion page.