By: Anthony Grgas, Field Engineer
Anthony is a Field Engineer with HEA and is currently working on commissioning several projects throughout NYC, including The Allen Hospital (NewYork-Presbyterian). This month, we are sharing a little about what he does when he’s off-duty – developing a flickering LED candle! Enjoy!
Genesis: As my wife and I were planning to get married in a barn, we were dismayed to find out the location we chose allowed absolutely NO CANDLES. It was a real shame; the place would look great with that type of lighting. But, it was also no surprise; the wood barn was at least 150 years old and it is all too easy to knock a small candle over. The place had LED candles as alternatives, but they looked too fake. Then the idea came to me… My wife didn't think I couldn't do it. Challenge accepted :)
Development and testing: I had been an electronics amateur for a while and I knew my way around RadioShack. I knew that in order to simulate a candle that can flicker in the wind with an LED, the LED first had to sense airflow before it could react to it. I managed to do it cheaply. The oscilloscope (yes, I have one) shows a voltage signal coming off of my self-made airflow sensor (using just diodes and resistors) and it worked really well. The last step was just to connect the sensor to a microchip that took the input from airflow sensor and translated it to varying voltages to an LED; flicker accomplished.
Working Prototype: It works and the sensor definitely picks up the slightest breeze.
The only problem is that the sensor works like a hot wire anemometer which requires a lot of battery power. It is definitely a work in progress – but it’s almost there!