Wednesday, February 20, 2013

Photoresistor and Speaker Circuit

Whoops! I lost my photoresister! Will update when I find a replacement.

Potentiometer and Speaker Circuit





Questions:

1. No, the speaker drops whatever voltage you put into it.
2. To make it louder, simply up the voltage!
3. Yes! But I wish the speaker didn't sound so horrible!

Potentiometer and LED Circuit

Questions:

1. 1023
2. 0
3. It must drop 2.5 V
4. It is outside of the LED's range of output

Switch and LED Circuit


Questions:

1. You would have to move the resister attached to the button to the other side.


Blinking LED Circuit


My Musical Instrument!





My instrument follows Crawford's model of interaction in the following ways: I listen to the sequence (Listen), think about the sequence (Think), and can then decide to alter the tempo with a potentiometer or change the sequence with a press of a button (Speak). My instrument responds to my input (Listen), executes a code based on that input (Think), and changes the output accordingly (Speak).

My instrument could be improved in many ways. Part of the problem is physical; I simply don't own as many buttons as I would like, so I am only equipped (currently) to make 4 different sequences. I also wish i had another potentiometer, which I would use to change the pitch in addition to the tempo. I also wish i had a better speaker, as this one is quite painful to listen to at any frequency. I also wish my instrument could make sounds other than just one (screeching) tone, but for this a better, more complex speaker is required. 

Wednesday, February 13, 2013

Capacitor Discharging Circuit with LED Decay


Questions:

1. The Capacitor discharges through the LED because, when the switch is not pressed, there is still a complete circuit, however now the capacitor is functioning as the "battery". The capacitor is connected to the ground too but the current in the circuit is not flowing that way, because of the capacitor's battery like properties. 

Capacitor Charging Circuit


Questions:

1. Adding a resister between the pushbutton and the capacitor slowed the rate at which the capacitor charged, resulting in a dimmer flash spread out over a longer time.



Dueling LEDs Circuit with Potentiometer




Questions:
1. The potentiometer in this circuit divides the current between the two LEDs. Depending on where it is turned two, the potentiometer will give more current to one light and less to the other.

LED Circuit With Potentiometer



Questions:

1. The resistor is necessary to prevent an exploding LED when the potentiometer is turned to offer the least resistance. 
2.The total resistance offered by the potentiometer and resistor is 10560 Ohms, so using Ohm's Law we get 5 = I * 10560 resulting in a current of .00047A.
3. There are also digital variable resisters. 


LED Circuit with Switch



Questions:
1. It wouldn't change anything.
2. It wouldn't change anything.

Simple LED Circuit



Questions:
1. The resister slows down the current, making sure there is not too much going into the LED.
2. Using Ohm's Law (5 = I * 560) and solving for I we see that this current has .0089 Amps runing through it.
3.Using Ohm's Law (5 = .015 * R) and solving for R we see that for the circuit to have 15mA of current you would need A 333 Ohm resister.
4. All of the Voltage must be dropped, so if the LED drops 2.2 V, then the resister must drop 2.8 V.





Breadboard