Month / September 2014

by fromjia

Making up lost times with my breadboard

Last week I didn’t do the breadboard and multimeter labs because of poor time management. Though we went through most of them in class and I was able to make my LEDs light up with the help of Benedetta and Sweta (thanks!), I figured that I should try them again on my own so that I get the fundamentals and reduce the chance that I’ll set anything on fire in the future.

Below are some of the results:

IMG_29201 LED with voltage regulator + 9V battery: Yay! It’s alive.

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2 LEDs connected in series

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3 LEDs in connected in series: Boo. I forgot that the voltage regulator converts voltage from 9V (batter) to 5V. Each LED uses about 2V, so 3 of them would need more than 5V. I wonder what would happen if I remove the voltage regulator, and let the 9V go directly to the series of 3 LEDs?

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3 LEDs hanging out in parallel: This time it works, because the voltage is not split up between each of the LED. Each LED uses the same amount of voltage in this case.

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3 LEDs in parallel: This time the red LEDs are much brighter than the green one. The red LEDs uses less voltage than the green one, so is this prompting the current to pass through the red ones and not the green one? Would this potentially damage the green LED?

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1 LED with Arduino built in 5V

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1 LED with switch OFF: This is strange. Why is the switch measured at 3.8V when it’s turned off???

IMG_29291 LED with switch ON: And now the switch is at 0V. Why? Is it because the switch acts like a piece of continuous wire when it’s turned on?

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2 LEDs in series with switch OFF: I tried this again with 2 LEDs and measuring at the end of the wires. Again, the switch measured at around 3V when turned off.

IMG_29382 LEDs in series with switch ON: Again the switch measure at very little V, 4.8mV which is 0.0048V, when it’s switched on.

 

 

by fromjia

Collective Memories – Experiencing the City Reliquary

cityreliquary_rock For my Applications experience, I was sent to the City Reliquary in Williamsburg. Though I’ve been living in New York for many years and have even passed by this place many times on the way to and from the G train, I’ve never taken notice of it. It’s amazing how much you miss everyday in the city if you don’t pay attention!!

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From the outside the City Reliquary looks like any other hipsterish storefront in Williamsburg. And as a matter of fact, they do share the front of the space with a hipsterish store, which confuses their visitors a bit. Many people came in to check out the store, not even knowing the back is actually a museum.

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This is Ben. Ben is the director of the City Reliquary and he was manning the vintage cash register on this particular Sunday. Ben is very friendly and enthusiastic. You would definitely feel bad going in the museum without donating when Ben’s around.

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The City Reliquary has a rotating exhibit as well as a permanent t collection. There are lots of interestingness, from a quasi naked doll cake to old photographs of New York childhoods to memorabilia from the 1964 World’s Fair.

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The back room displays a signage from the old 2nd Ave Deli, along with rows and rows of old pencil sharpeners and Chinatown styled coffee cups as well as vestiges of New York folklores.

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Even the bathroom is decorated with collective memories.

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There is a spacious (by NY standard) backyard, where you are welcome to chill with beer and snacks. Someone had made a shrine of New York landmarks with a bathtub.

All in all, the City Reliquary was a delightful treat. It’s a place that makes New York seem as if it’s a big eccentric family that never throws anything away and holds on to a past where magic is always around the corner.