After listening to Scott Hanselman’s podcast on the NetDuino I was really interested in the idea of building my own hobby projects and learning electronics. I’ve got two projects that I want to build, both of them rather ambitious 😛
The first idea was to build a Snowbot (snow blowing robot) and the other idea was to build a home alarm system. I’m starting with the home alarm system as it in theory should be easier to build.
This is what I would ideally have in a home alarm system:
- Networked, so that I can arm/disarm and check the status over the web
- Email alerts
- Sensors on all the doors and windows
- 2x Motion sensors (main floor and basement)
- Bloody loud alarm system
So looking at the best places to start learning how to do all of this I decided it would be best to start learning electronics. The best resources I have found so far are:
- allaboutcircuits.com – an education website about electronics
- MAKE: Electronics the book (totally awesome)
- MAKE: Magazine videos on youtube are really well done and entertaining
I tried using software to model circuits but found them really confusing. I tried Tina-TI, while it is really good for certain learning, I have found that actual hands on with components is easier to learn from.
I decided to buy some basic electronics components. Looking through the Make electronics book and searching on the web i found this product, a starter electronics kit for the first few chapters of the MAKE: Electronics book. I noted down what i thought were the key components and went to the local electronics shop and bought them for around $150 including digital multimeter.
The main components I bought were the multimeter, a $15 dollar pack of assorted resistors (definitely worth the money), various capacitors, some NPN transistors, breadboard and 9v supply, assorted LEDs and wires.
After reading up on DC theory at allaboutcircuits.com I started building some really simple circuits, with the home alarm system in mind.
I tried to visualize what components the alarm would need to have to make this alarm system. At its simplest it would need the following:
- Blinking LED
- Circuit that would break when a window/door was opened
- Some sort of keypad interface (ideally touchscreen)
- Netduino as the microcontroller
The next post in this series will cover the alarm’s blinking LED.