Fred Fest Videos Out

 

My band played at Fred Fest 2018 in the East Campus courtyard at MIT. It was a great time. Playing music in front of a crowd is always a potentially anxious experience but I throughly enjoyed the experience.

Album is next, keep your ears tuned. T-shirts maybe as well?

Fred Fest Success

 My band played at the annual East Campus concert called "Fred Fest" last Saturday. We had a 30 minute set from 7 to 7:30pm. There was definitely some tension about our ability to perform but we ended up not messing everything up.

I'm looking forward to more gigs with these guys. :)

The night included Valleyheart, Bat House, and Air Traffic Controller. Check them out!


Biking to Boston Mini Maker Faire

 Last weekend, I headed over to the Maker Faire event in Boston held at the Boston Children's Museum. It was a good time and I saw a lot of neat projects.

There was a great represenation of artists and craftspeople. I saw glasswork and welding. I'm sure this sort of event helps introduce younger people in the maker sphere of influence.

High Lumen Output LED

 I was playing around with this fancy 12V arrayed 3 parallel, 3 series, LED for generating highly diffuse white light. These packages are fairly good at modulating overall light output as a function of both current and voltage. Starting to turn on at about ~10V and getting warm anywhere north of ~12.5V.

Definitely thinking of incorporating these components in electric vehicle concepts. Headlights are important, especially at night.



Unpacking an Old Smoke Detector

 I have been meaning to open this for a while now. This PCB came off an old smoke detector I found in a pile of electronic trash. A lot of these old smoke detector have two major enclosures inside the main unit. The one on the right houses the loudspeaker that plays a ~10kHz sound (also goes off for low battery. The one on the left houses an Am-241 button. The Am-241 releases a torrent of alpha particles into a metal plate. The metal plate is thus partially charged at any given time. If smoke enters the black enclosure, it attenuates the alpha particles at a much greater rate than normal air. The lack of alpha particles charging the metal plate causes the attached chip to send an alarm signal to the loudspeaker.

Hard to see here, sorry, but the small dark circle in the middle of the metal plate is an Am-241 button.

EL Wire teardown

 I bought a small, 2-AAA battery powered, EL wire kit on the internet a while back. The pocket sized, plastic assembly fits plainly in a pocket and can illuminate 5 ft of EL wire. I wanted to figure out how the tiny form factor takes 3V DC and bumps it up to a much higher voltage, alternating signal.

There is an interesting IC on the board that does a simple job well. There is a variable clock on the power rail. By setting a pin on the clock pin high momentarily, a logic level circuit flips the timing frequency at which the power rail is connected to the gain staging (prior to the transformer). This gives the EL wire a flashing behavior.





LED curtain revitalization

 This past weekend I figured out the wiring for a large LED matrix on my dorm hall. I had previously used the software written to interact with the raspberry pi controller for the LED matrix but I did not know how it was originally wired.

After looking into the frame, I figured out how the series of ws281x LEDs were configured. This allowed me to setup an arduino with neopixel code to test the LEDs.

 The original raspberry pi driving the LED matrix was having issues with network connectivity. Likely the result from MIT "natting" their IvP4 addresses. However, I had some luck connecting directly to the Pi.

Out in the Fells this Weekend

  Instead of driving out to New Hampshire, the Cedar St friends decided to hike closer to home and visited the Middlesex Fells reservation. ...