A 1920’s Doorbell is Upgraded with 2010’s Technology

When you move into an old house, you are bound to have some home repairs in your future. [Ben] discovered this after moving into his home, built in 1929. The house had a mail slot that was in pretty bad shape. The slot was rusted and stuck open, it was covered in old nasty caulk, and it had a built-in doorbell that was no longer functional. [Ben] took it upon himself to fix it up.

The first thing on the agenda was to fix the doorbell. After removing the old one, [Ben] was able to expose the original cloth-insulated wiring. He managed to trace the wires back to his basement and, to his surprise, they seemed to be functional. He replaced the old doorbell button with a new momentary button and then hooked up a DIY doorbell using an XBee radio. [Ben] already had an XBee base station for his Raspberry Pi, so he was wrote a script that could send a notification to his phone whenever the doorbell was pushed.

Unfortunately, the old wiring just didn’t hold up. The push button only worked sporadically. [Ben] ended up purchasing an off the shelf wireless doorbell. He didn’t want to have to stick the included ugly plastic button onto the front of his house though, so [Ben] had to figure out how to trigger the new doorbell using the nice metallic button. He used the macro lens on his iPhone to follow the traces on the PCB until he was able to locate the correct points to trigger the doorbell. Then it was just a matter of a quick soldering job and he had a functional doorbell.

Once the electronics upgrades were complete, he moved on to fixing up the look of the mail slot. He had to remove the rust using a wire brush and sandpaper. Then he gave it a few coats of paint. He replaced the original natural insulation with some spray foam, and removed all the old nasty caulk. The final product looks as good as new and now includes a functional wireless doorbell.

We’re big fans of salvaging old-school home hardware. Another example that comes to mind is this set of door chimes with modernized driver.

Python powered sprinkler system wastes no water


One thing that annoyed [Jashua] to no end was hearing his automated sprinkler system kick on in the middle of the night, when it had rained earlier in the day. He wished that his sprinklers were a bit smarter, so he decided to give the system an upgrade.

Rather than pay hundreds of dollars for a more sophisticated automation system, he spent about $45 on supplies and scrounged together some items he had sitting around the house to make a rain-sensing module of his own.

The resulting project, Pysprinklers, uses Python along with a handful of components to better manage his water usage. He got his hands on a cheap rain gauge, and modified it with a game controller and a set of magnetic surface contacts. If there has been a significant amount of rain in the last 24 hours, his system will prevent the sprinklers from turning on. Additionally, if there is rain in the forecast, the sprinklers will be delayed a bit to see if rain makes its way into the area.

We’re all for saving money (and water), so we think [Jashua’s] system looks great, especially because he ended up using a handful of things he already had on hand.

DIY servo activated door lock with capacitive touch keypad


Since he was a kid [Giorgos Lazaridis] has always loved the idea of having an electronic door locking mechanism, and now that he has the means, he’s decided to construct one for securing the door to his apartment. He calls the project “simple and cheap”, though we’re not sure about the first part. Taking a look at his very detailed build log, you can see that he has invested quite a bit of time and effort into this impressive project.

Buying an off the shelf product was expensive and not a whole lot of fun, so [Giorgos] disassembled his door’s locking mechanism to see how he might be able to actuate the lock electronically himself. With minimal modifications to the lock, he was able to add a servo which reliably opens the it when triggered.

With the mechanical portion of the project out of the way, he spent a great deal of time working on the door’s electronic components, including the PIC-based controller and capacitive keypad. The keypad proved to be a bit of a problem, but after a few revisions he found a design that was both reliable and pleasing to the eye.

The locking mechanism works pretty well, as you can see in the video below, and [Giorgos] is quite pleased with the results.

Continue reading “DIY servo activated door lock with capacitive touch keypad”

Simple household status system


[BrianH] decided that he no longer wanted to venture outside on cold or rainy days just to check if the mail had come, so he built himself a notification system that would alert him if the postman had stopped by. Additionally, he admits to being forgetful on occasion and wanted a way to monitor whether or not he forgot to close the garage door. His Instructable details how he accomplished both of these tasks with the household monitor he built around an ATmega168. His project uses a mailbox mounted photoresistor to determine when the mailbox has been opened, and a reed switch that is triggered when the garage door has been opened. If either of these things occur, a beep is emitted from his notifier, and the appropriate status LED is lit. Simply monitoring whether the garage door has been opened is not all that helpful, so he programmed his notifier to beep persistently at 10-minute intervals if the garage has been left open for more than an hour.

His hack is pretty useful, but he does mention that there is an inordinate amount of wiring that needs to be laid, citing his driveway repaving as a great opportunity to do so.

Making Nixie tubes at home

[Aleksander Zawada] makes vacuum tubes in his home. One of the most challenging builds he has taken on is to produce a working Nixie tube. He describes the process in a PDF, covering his success and failure. It seems the hardest part is to get the tube filled with the proper gas, at the proper pressure, and firmly seal it. In the end he managed to make a tube with three digits (0, 1, and 2) that worked for about 700 hours before burning out.

[Aleksander] joins [Jeri Ellsworth] on the short list of hackers who can pull off extreme industrial manufacturing at home. Kudos.

[Thanks Duncan]

Jeri makes integrated circuits

[Jeri Ellsworth] made this silicon inverter at home, by hand. It took her two years to get the process figured out and achieve something we didn’t think was possible. The complexity of manufacture, and the wide range of tools and materials needed seem insurmountable but she did it anyway. Her home chip fab Flickr set is well commented and details her work area and part of the processing. If you’re hurting for more check out her 40 minute Metalab talk which we’ve embedded after the break.

If her name sounds familiar but you just can’t place it you may know her from The Fatman and Circuit Girl. We’ve also featured some of her hacks, such as her Pinball challenge against [Ben Heckendorn], and her giant Etch-a-Sketch.

Continue reading “Jeri makes integrated circuits”