Repaired Microwave Keypad Looks As Good As New

June 23, 2011 by Mike Nathan 15 Comments

microwave_keypad_repair

Instructables user [Rohit] had an out-of-warranty microwave with a broken membrane keypad. Much like our friend [Alexandre] from Brazil, he found the cost of replacement parts beyond reasonable, so he had to find a way to repair it instead.

He disassembled the front cover of his microwave to get at the main controller board. Once it was detached, he removed the keypad’s cover to get a closer look at the matrix underneath. While taking notes on how the matrix was wired, he found that some keypad traces connected to other traces rather than buttons. He says that they are likely used by the microwave to detect that the keypad is present, so he made sure to short those traces out on the controller board when he wired everything back together.

He replaced the aging keypad with microswitches, but rather than mount them on the front panel of the microwave, he drilled holes for each switch so that he could mount them inside the face plate. Once everything was wired and glued in place, he re-mounted the keypad’s cover. Now the microwave looks stock but has firm, reliable, user-serviceable buttons that are sure to last quite a while.

Roomba Shares All Of Its Daily Activity On The Web

June 21, 2011 by Mike Nathan 10 Comments

Instructables user [matchlighter] wanted to see what he could program his Roomba to do, so he decided he would make his little cleaning machine report its status on Twitter whenever something happened.

He popped open the Roomba’s case to access its serial connector, crafting a simple interface cable from some spare Cat5 he had sitting around. He added a small voltage regulator between the Roomba and his Arduino in order to protect it from the high power output present while the Roomba is charging. Once the proper bits were in place, he hooked the Roomba’s serial interface to the Arduino and attached a SparkFun WiFly shield to allow for wireless communications. After a bit of coding, the Roomba was sharing its activities with the entire world on Twitter.

Not only did he want the Roomba to tweet, but he decided that he also wanted the ability to control it from the web. He created a simple interface using a handy library he found online and was sending cleaning commands to the Roomba in short order.

While there is no video of the Roomba in action, you can check out what it is up to here, and there’s plenty of code to be had on his Instructables page.

Turning Spotlights Into Soft LED Nightlights

June 20, 2011 by Mike Nathan 7 Comments

led_spotlight_retrofit

[Bob] had a couple of bright, 12V halogen spotlights in his hallway that didn’t get much use. Rather than toss them out or leave them sitting idle, he decided to replace the bright bulbs with dimmer LEDs that he could keep lit through the night.

He opened up the spotlights, removing the bulbs and the built in mirrors before fitting them with 350mA LED pucks. The pucks were mounted to a pair of L-shaped aluminum scraps, which serve as both a mounting plate and heatsink. When running, the underdriven LEDs barely heat the aluminum plates, so he is pretty confident that the lights are adequately cooled.

The orange LEDs provide a nice warm glow in his hallway, and he says they are perfect for late night trips to the fridge. They currently stay lit all the time, but [Bob] is considering adding a light sensor to turn them on them automatically, as well as a PIR sensor to increase the brightness as someone passes by.

Disappearing Kitchen Island

June 14, 2011 by Mike Szczys 31 Comments

[Tim Thaler] has been redoing his home, adding some fancy automation here and there. But when it came to the kitchen, he went all-out by installing an iPhone controlled disappearing island. In the video clip after the break you can see [Tim] dial up some extra counter and storage space from his smart phone. One click causes it to slowly rise from the depths, shedding the carpet tiles as it goes.

Directly beneath the kitchen is an unfinished storage room. [Tim] framed a hole in the floor above, and sourced a used scissor lift for about $380 to do the heavy lifting. It operates smoothly and isn’t all that loud. It sure makes for an interesting feature if he ever decides to sell the place.

We thought it was a nice touch that the storage room hiding the mechanical parts of the hack has a hidden entrance. You must travel through the billiards room in the basement to access it, turning the ball rack to unlatch the entrance.

Continue reading “Disappearing Kitchen Island” →

Reverse Engineering Wireless Weather Stations

June 13, 2011 by Mike Nathan 26 Comments

lacrosse_wireless_temp_sensor

[Fred] got a La Crosse wireless weather station as a gift and thought the LCD display was great, but he was dismayed that there was no means of extracting the temperature data for use on a computer. He thought that the modular design of the system would make it great for use in his home automation project if he could only get his hands on the data.

He tore into the base station and started looking around for easy places to get at the data he was looking for. He thought about tapping into the bus that controls the LCD in hopes of finding an easy to decode signal, but the weather station used a proprietary chip with an integrated LCD controller, making it all but impossible. Instead, he started sniffing the data coming across the wireless link, and while he didn’t quite yet know what he was seeing, it was a start.

He sniffed the signals using Audacity, and eventually found that the base station received 40-bit data bursts from each sensor. He dug further, and with the help of some data he found online, he was able to decode the data packets. The last hurdle he ran into was figuring out how the system’s CRC encoding worked. It took a bit of work but he eventually got it, and can now record data packets knowing that the data has come over the air intact.

So far, it looks like his temperature monitoring system is working quite well, though he has several improvements planned for the near future. If you have a similar unit and are interested in extending its capabilities, [Fred] has posted plenty of code on his site.

Fixing Motorized Window Shutter Battery Problems

June 12, 2011 by Mike Nathan 4 Comments

rolling_shutter_battery_fix

Living in a brushfire-prone area, [Erich] had a set of roller shutters installed to protect his home. Mains power can be spotty in emergencies, so the shutters are powered by NiMH batteries which are housed inside the shutters’ remote control units. After encountering a good handful of dead batteries, he decided it was time to search around for a better means of powering the shutters rather than pay another $80 AUD for batteries that he knew would fail in short order.

After disassembling the shutters and the remotes, he found a litany of problems. The remotes are ATMega-based, so he assumed the programming was robust, but he found that the charging algorithm was quite poorly implemented. The batteries were allowed to get extremely hot while charging, a result of the fact that charging was done for a set period of time rather than monitoring battery voltage. Additionally, the shutter motors required a 4 amp instantaneous current when activated, something that seemed to contribute to the quick draining of the 1500 mAH battery packs.

To remedy his issues, he upgraded to a much larger sealed lead acid battery pack, which he mounted in a wall cavity. The remotes were tweaked to add a modular power plug, enabling him to easily connect and disconnect the remotes as needed. Not only did he save a ton of money on constantly replacing batteries, he’s got a nice 12v power supply in the wall that he can tap into at will.

Hacking Into Your Router’s Administrative Interface

June 9, 2011 by Mike Nathan 21 Comments

zte_zxdsl_router_hack

[Arto] recently upgraded his home Internet subscription from an ADSL to VDSL, and with that change received a shiny new ZTE ZXDSL 931WII modem/wireless router. Once he had it installed, he started to go about his normal routine of changing the administrator password, setting up port forwarding, and configuring the wireless security settings…or at least he tried to.

It seems that he was completely unable to access the router’s configuration panel, and after sitting on the phone with his ISP’s “support” personnel, he was informed that there was no way for him to tweak even a single setting.

Undaunted, he cracked the router open and started poking around. He quickly identified a serial port, and after putting together a simple RS232 transceiver, was able to access the router’s telnet interface. It took quite a bit of experimentation and a good handful of help from online forums, but [Arto] was eventually able to upload an older firmware image to the device which gave him the configuration tools he was looking for.

Aside from a few Ethernet timeout issues, the router is now performing to his satisfaction. However, as a final bit of salt in his wounds, he recently read that the admin panel he was originally seeking can be accessed via the router’s WAN interface using a well-known default password – frustrating and incredibly insecure, all at the same time! He says that he learned quite a few things along the way, so not all was lost.