Lab 4 - Schematics, Ohm's Law, and Potentiometers

Description:

Schematics are very important to graphically communicate how a circuit is wired.  The power source, ground, and all kinds of components have symbols that represent their function.  I use schematic drawings a lot for solving voltage drops and total resistance in a circuit.  To figure out voltage, amperes, and resistance mathematically we need to use Ohm's Law.  Ohm's Law can be summarized as a simple equation that is Voltage equals Current times Resistance.  If one knows at least two measurements, this formula can be used to solve for the unknown.  For instance, we want to know which resistor makes the LED shine the brightest and we know in order for LED to shine it needs 2.5 volts and 20 milliamps.  A resistor soaks up a certain amount of volts from the power source and is divided by the resistor and LED.  The larger the resistor is the dimmer the LED will be.  There is another type of resistor called a potentiometer, which is a variable resistor.  Using a Philips screw driver we can change the resistance that can the LED shine or dim by turning a dial. 

Lab 3 - Using a Multimeter

Description:

The multimeter is a very important tool to verify if our components are working on the breadboard.  One of the things we can verify is continuity.  In other words to see if a the component or wire conducts electricity, so if it does our multimeter will make a beep sound.  The continuity setting can also tell us if there is an open on the circuit board.  Another setting we can use to verify out parts is measure voltage.  We can measure our power source or the individual components on a circuit board.  Using Kirchhoff's Law we can make sure the voltage drops across the components of a circuit board equal the power source.  There are two settings for measuring voltage, which are AC and DC.  The multimeter can also measure resistance.  Components like resistors will have different amounts of resistance, which can be determined by using the 4 Band Code.  The first two stripes of colors represent the first two digits in the number.  The third color tells you haw many zeros to add after the first two digits.  The fifth band tells you the percent tolerance. 

Lab 5 - Switches and Relays

Description:

I learned that switches and relays are two different things.  Switches turn on or off by manually flipping or activating a switch.  A relay is a switch that is turned on or off by an electric signal or electricity.  A programmable micro controller is something that can use a relay to turn on and off a motor.  A switch usually is very simple and has three or two leads depending on its function.  There are a wide variety of switches that are available for purchase such as knife switches, Mini Slide switches, toggle switches and push button momentary switches.  It is always a good idea to connect an LED, so that you know your switch is providing power.  Relay switches often have coil or solenoid that turns it on or off.  In order for the coil to activate it needs a certain operating current and voltage.  The relay we used had a ten pins.  The first two pins energize the coil and the others a series of switches that are either in a connected state when activated or in a not connected state.  Relays are very important to activate other relays, components, and motors for the robot we will build in the coming days. 

Lab 2 - Introduction to Using a Breadboard

Description:

What can I say, Breadboards are awesome!!!  They allow people to make an easy and simple circuit for prototyping before.  One can troubleshoot their circuit and get rid of the "bugs" before components are soldered to a printed circuit board.  Its a simple square peace of plastic with lots of holes in it.  There are four columns located on left and right edges, and are connected vertically.  The columns are used to provide power to the circuit.  At the very center of this piece of plastic is a vertical slot dividing two columns of solderless holes.  These holes are connected horizontally in rows.  There are five holes for every row and are not connected to each other.

To demonstrate how the breadboard is used, we connected our power source into the rails and inserted a LED and resistor.

Lab 1 - Intro to Soldering and Building Power Supply

The title goes here

Description:

Soldering is easy!!!  We just need to do it safely and without harming our fellow classmates.  Always assume the soldering iron is hot, because it will burn so bad:(

Don't touch the tip, EVER, and do not set the soldering iron on things that are flammable.  That's not good!  If you accidentally drop your very hot soldering iron, do not use your ninja like reflexes to catch it.  You will most likely the end that burns you.

The purpose of Lab 1 is four newbies to practice our soldering skills by doing just that; soldering surplus components on a piece of PCB.  The components are to neatly lay flat on the board and not off to one side.  We are to heat lead of the component and conductive pad of the board to prepare it for soldering.  Only use enough solder to cover the pad and should look like a tapering mountain.  Once you are done, cut the leads off

Power supply, also easy!!!

We are given a 5V power supply, but it is not suited for use on a bread board.  We are to cut the end off and split positive and negative wires.  Next we splice the power supply wires with solid wires that are about 3 inches long.  I wrapped one wire around the other and soldered the exposed wires.  For safety shrink wrap was put over the solder for addition protection from short circuiting.

Very Fun!!!

  

My first few attempts were messy.

I checked the voltage and it is 5V's, horray!!!

I used too much shrink wrap.

The bumps are where I spliced the wires:)