Doing some clean up around the house I found an old wireless doorbell but not the remote to activate it. I started to toss this in the trash. Rather then throw it away I decided to turn it into an alert box for connection to an Arduino or maybe my PC to alert me when something needed my attention. Here is the result, an awesome sounding bell and a very bright LED, driven by two power MOSFETS. Just about anything can drive the signals to make a bell or flash a bright red LED.
The enamel coated, transformer wires come from the bell ringing solenoids. Only one is used. The way this doorbell was setup, one coil would ring both bells and one would ring just the longer bell. I intended to remove the shorter bell so I only connected the coil for the long bell.
A power N-Channel MOSFET controlled from a digital output drives the gate to turn on the FET which pulls down on the coil to ring the bell.
A second FET pulls down the return on a high brightness LED. You can easily see the LED though the plastic cover. You might see this LED from the Moon if it were not covered. This is a 1 Watt LED I got some time ago, it is one of the few parts that was not scrounged here.
The MOSFETS were new as well. I tried to use one I had scrounged but it required too much gate to source voltage and I ended up blowing it.
Here is the finished box. The wires coming out of the side are currently connected to my Umbuntu box. I have some custom software that I’m working on. it rings the bell or flashes the LED. I’m thinking of connecting this to IRC to let me know when someone mentions my nick (uCHobby). But I need to learn a but more about Linux software development first. It could also be driven by an Arduino. I might wire this up to my front panel project which will use an Arduino to control switches, lights, meters etc…
Posted in Uncategorized.
STMicroelectronics is working hard to gain ground in the microcontroller market. The STM8S-Discovery kit cost $7 and features a small 8Bit MCU with I/O, a capacitive touch button, USB interfacing and Debugging support built into a detachable module. The attached debugging module can be broken off and reused. Development tool are free and provide full source level (sing step etc) debugging.
We purchased two of these kits from Mouser Electronics for $7/each. I have not yet installed all the development tools but the board looks very easy to use.
Have any of you played with this? Seems like a great way to get started with Microcontroller hobbies. Might not be as easy as the Arduino but at under $10 it could be an inexpensive way to start. Comments?
A good bit on information and a video can be found at the STM8S-Discovery kit website.
Posted in Development Tools, Discovering, Electronics Links, Microcontroller, Parts.
Two plastic shelf kits from Lowe’s assemble into a 24 inch (2 foot) deep, 9 foot long standing work bench. The link above is not exactly the model displayed in the picture. These shelf units are available in different sizes and styles for $40-$80 each. While assembly the two shelf units stop when you are around waist high, 3 of 5 levels. With the left over’s, make a third short shelf and a double high self for the center section. Continued…
Posted in Discovering, Hacks, Ideas, Parts, Projects, Scrounging, Scrounging Parts, Workshop Tips, Workshop Tools.
This solar garden/path light was found at Target for $3! Nothing special about path lights, and the low price is no surprise in our times but this item looks very interesting for home projects. Instead of the fancy curved “good looking” enclosures it’s a simple cube. Very easy to reuse this enclosure. Reuse the enclosure, rip out the guts and build something cool. Use the Led, Battery, and the stake part to mount and power your latest creation. These kinds of things inspire me. I am compelled to find something interesting to do with it.
More details after the jump… Share your ideas in the comments
Continued…
Posted in Discovering, Hacks, Ideas, Projects, Scrounging, Scrounging Parts.
By admin
February 23, 2010
MySQL problem
Just a quick note about the uCHobby web site. We have been having some trouble with our database server not starting as a service. If you see a database error when visiting please try again later. I can manually start the MySQL DB so the site will return. We should have this issue sorted soon.
Giveaway Program Ends.
We are discontinuing the giveaway program. It was great fun to give away parts to hobbyist but I want to put more focus on my own projects for awhile. I have gotten lazy, using submissions rather then projects of my own.
We enjoyed the giveaway program and it may return in the future.
There are lots of places to publish hobby projects compared to when we started the giveaway program. Let us know when you publish a home project. I hope to have a short post now and then with links to interesting projects around the web.
Future Articles
Expect to see some more interesting microcontroller projects here in the near future. I am playing with an all terrain robot project, more audio developments, new breadboard adaptor designs, and Android software development.
Go learn something, have fun, and share! Let us know how your doing.
Posted in Projects, uC Hobby Site.
By admin
January 24, 2010
CAT5 Ethernet cables to connect audio from my PC to my room stereo. My shop has a nice stereo on the far wall away from my PCs and work bench. Rather then purchase a long audio extension cable I scrounged up some CAT5 Ethernet cable and audio connectors, a few quick splices and a 30 foot audio cable is born. Sounds great!
Continued…
Posted in Discovering, Hacks, Ideas, Parts, Projects, Scrounging, Scrounging Parts, Workshop Tips.
By admin
January 23, 2010
Just received an XMOS XK-1 Development Kit in the mail as part of a Design Challenge hosted via Trossen Robotics.
XMOS has in interesting architecture, something new to explore. I am especially interested in the parallel processing features and how code is developed. Development tools are free so this might be a great part to hobby with.
From the XMOS site:
The XMOS architecture makes it practical to use software to perform many functions that traditionally have been implemented in hardware, for example interfaces and I/O controllers. Both input and output operations can be timed to a local clock or an externally provided clock. The architecture is both multi-threaded and event-driven. Threads can be used to define independent tasks; the event mechanism enables fast and controlled responses to a multitude of signals.
Continued…
Posted in Contest, Development Tools, Discovering, Microcontroller, Parts, Projects, Review.
By admin
October 25, 2009
Google Wave is here and it looks like a great too for hobbyist that want to share project information and get help. We have even started a Wave for Arduino information and helped our first hobbyist with a power supply issue on his project. Mark Campos and I found that Wave worked very well for real-time troubleshooting and hatched the idea that people should start public waves for their Arduino projects. To make projects easy to find use “Arduino” and “Project” as tags for the wave.
More instructions after the jump…
Continued…
Posted in Arduino, Development Tools, Discovering, Electronics Links, Ideas, Microcontroller, Projects.
By admin
October 12, 2009
Jonathan Thomson submitted this useful article about converting a low cost cell phone USB cable into and easy and cheap way to connect to an Arduino microcontroller setup. Jonathan found a cable for less then $3 which can be hacked to perform the same function as the typical $20 FTDI USB cable often used in Arduino projects.
Jonathan submitted as part of the uCHobby Giveaway project and has selected to receive a Plug-in Bread Board Power Supply Kit for this article.
Continued…
Posted in Arduino, Development Tools, Discovering, Electronics Links, Hacks, Ideas, Microcontroller, Parts, Projects, Scrounging, Scrounging Parts, Workshop Tips.
