Electronics This is a link to the lab instructions.
Please put your observations on this weeks lab here.
Here is a picture of the Lab (put picture here) It was really neat to see the LED's light up. I made one smoke when I used too small a resistor. When I put two in a row ...... happened then I took out the resistor and ....... happened
This lab was fun. I went in early one morning, and the floor was pretty empty. I was actually nervous about soldering, as I had never done it before. However, aside from realizing that I had to run to radio shack to get a small roll everything went smoothly soldering. The first LED lit up without a hitch, but when I attempted to light up three at once, it didn’t work. I wonder if this is because maybe they aren’t getting enough voltage to light up all three. I could get two to light, and that would make sense. I remember the LEDs? take something like 2 volts, and since we have 5 volts running through our system, that would make the first pass 3 volts onto the second, which passes one on to the third, and the third cant pass any on to ground. I wonder if that is how it works...I might be wrong and anyone feel free to correct me. The switch went off fine as well. The variable resistor was not as smooth. I hooked up the pot to the system and the LED was blinking in a funny way not seemingly related to the potentiometer. The pot began to smoke, so I unplugged the board. I then hooked a new pot up and the LED's brightness was able to be controlled. I included a photo of the first LED lighting. I was pleased when it happened. Aaron
Bennett - Everything went pretty smoothly on this one. I got the necessary parts over at the computer store, and now that I have seen some of the nifty extras that came with other people's kits, I may just have to spring for it. I took Michael's advice and used the multimeter to test the voltage throughout building the circuit, make sure I matched up the positive and negative correctly when soldering the converter piece. Had it halfway soldered when I realized I had switched black for red. Got the right resistor in there, but the lab seemed to be out of switches. I went with the touching-two-wires-together method, while Sai salvaged one from the parts shelf. The first little green LED lit up, no problem. Got another in the series and they both lit. But I guess there was too much resistance to power 3, they wouldn't light up. So back with 2 LEDs?, I found again that the lab was out of pots or other variable resistors (gotta get the kit). Carlyn was kind enough to dig out some pots and photocells out for us, and give Sai, Kati and myself a little lesson on how to wire them up properly. A few solders later we found that the pot had to wired into ground too, not just into the LED, in order for it to light. Got those 2 LEDs? dimming on and off. Huzzah.
Joseph - My Lab1 was fine, no troubles.
Xiaochang - Everything was pretty straight forward in this lab -- no problems came up. In the second set-up, with the series of LEDs?, I could only get two in a series to light up. With three, there was apparently not enough power and nothing much happened. The portion with the variable resistor I used a pot and had no problems, other than the fact that I was unable to resist almost burning out my LED playing with it. More on the experimental section later. Photos will be posted in my journal
Kate - Lab 1
Things I have learned:
- the power switch has a little symbol on it that shows which of the two connections is ground and which is power
- it is very important to check the labels of the resistors according to which color they are (eg. I was using a 110 ohm resistance, which I thought was good for the two bulbs, 1.7 LED voltage/ 20 LED current/ 5 total voltage, that should have only needed 82 ohms resistance. Little did I know that the resistor I had picked up was K ohms! I figured the extra ohms of resistance were the reason the LED did not light up. I checked the colors and found the correct amount.)
- the amount of resistance can be read according to the colors, each color being a different amount or resistance. The numbers are then added up to determine the total amount on each resistor. I think...
- soldering is an art
Rocio week 1 - Building my first circuit.
I met with Kate and together found out how to make an LED turn on. So exciting!
The electrons trip
They come from the 5-15VDC power supply, they go through the power supply connector, to the switch, to the 5V regulator, to the 220 ohm resistor, to the LED and finally to ground.
LED information. Voltage required and mA (miliams-current-1000ma=1amps): http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=94511
LED series resistor calculator: http://ourworld.compuserve.com/homepages/Bill_Bowden/led.htm
Kazu - Link
Joanna - Lab 1
kati london - Lab1
Angela Pablo - Lab 1
Viviana Espinosa - I tried it, worked fine, had still some trouble deciding where to put the power supply connector. Here are my picts.
April 9th - I went back to this lab. I wanted to figure out how the photocells worked, since I couldn't get it to work at first. I am very pleased with the results. I know it may be a bit late, but I wanted to take full advantage of the course, and didn't want to leave without figuring this out. I will also be using an application like this with my final project.
Won Sup Shin - http://happytorture.blogspot.com/
Sai - Sorry, I'm just starting to figure out where things go on the wiki. Reflections on the first lab (like all the others) can be found here.
Christin My First Breadboard