ilyas post 4

Fault finding problem:

When doing a fault finding problem i came across wire point  3 this is what happens when it was cut off.
point 3 The yellow LED keep turning on always.
The pin10 will get 0v and a pin9(signal voltage) is always higher than the pin10. Therefore, the current flows through the yellow LED and pin11(earth) of voltage rail and the yellow LED always turns on.


Heres a video clip i recored after i fixed into the and when i connected it to a car it shows when the car is running lean normal or rich.

Electronics Components 

Zener Diode

A Zener diode is a special kind of diode which allows current to flow in the forward direction same as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener voltage." The device was named after Clarence Zener, who discovered this electrical property.

A Zener diode exhibits almost the same properties, except the device is specially designed so as to have a greatly reduced breakdown voltage, the so-called Zener voltage. By contrast with the conventional device, a reverse-biased Zener diode will exhibit a controlled breakdown and allow the current to keep the voltage across the Zener diode close to the Zener breakdown voltage. For example, a diode with a Zener breakdown voltage of 3.2 V will exhibit a voltage drop of very nearly 3.2 V across a wide range of reverse currents. The Zener diode is therefore ideal for applications such as the generation of a reference voltage (e.g. for an amplifier stage), or as a voltage stabilizer for low-current applications.

Capacitor  

In a way, a capacitor is a little like a battery. Although they work in completely different ways, capacitors and batteries both store electrical energy. It does this by providing ground when there is an open circuit (switch is open). This storage of electrical charge prevents voltage spikes from happening. A capacitor consists of two metal plates very close together.When connected to a battery or a power source electrons flow into the negative plate and charge up the capacitor. This charge still remains when the battery or the power source is removed. The amount of charge a capacitor can store depends on the capacitance of the capacitor (measured in Farads F). Capacitors are also used in circuits to smooth-en out the current flow. This allows for the circuit to have a constant smooth flow of current. 

for more information please visit this to find out how it really works 

http://electronics.howstuffworks.com/capacitor1.htm

Relays

A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. Relays are used where it is necessary to control a circuit by a low-power signal (with complete electrical isolation between control and controlled circuits), or where several circuits must be controlled by one signal. 

Relays allow one circuit to switch a second circuit which can be completely separate from the first. For example a low voltage battery circuit can use a relay to switch a 230V AC mains circuit. There is no electrical connection inside the relay between the two circuits, the link is magnetic and mechanical.

http://www.kpsec.freeuk.com/components/relay.htm

Mosfets

metal–oxide–semiconductor field-effect transistor

It is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first proposed by Julius Edgar Lilienfeld in 1925. In MOSFETs, a voltage on the oxide-insulated gate electrode can induce a conducting channel between the two other contacts called source and drain. The channel can be of n-type or p-type

Hybrid electrical vehicle 

What makes a hybrid car so fuel-efficient? It's quite simple — they only burn gasoline when needed. That's because, as the term implies, hybrid cars have two different power plants under the hood: a powerful electric motor and a conventional gasoline engine. The electric motor, powered by a stack of rechargeable batteries, is the primary workhorse for moving the car during slow-speed driving — such as through a residential neighborhood or in stop-and-go urban traffic.

During coasting and slow-down phases when a driver lightly taps on the brakes, the car's wheels are automatically engaged to an electrical generator. The generator creates an extra "load" to assist the brakes in slowing the car down, but more importantly, it converts the car's mechanical energy back into electricity to recharge the car's batteries.

At higher speeds, such as steady highway cruising, computers automatically switch on the gas-burning engine, which then takes over as the primary driving force of the car. Typically, the small engine is designed with variable valve timing intelligence, or VVT-i, and other advances to ensure that the fuel is burned most efficiently and completely.

But both the electrical motor and gas-powered engine can also operate in conjunction. For example, if more power is needed to merge onto a highway or pass a tractor-trailer truck, the on-board computers will automatically activate the electric motor to provided the needed acceleration boost.

Hybrid proponents say the power combination offers consumers the best of both an electric car and a conventional gas-fueled vehicle. At complete stops — say, in rush-hour highway traffic where most car engines are spent idly wasting fuel — the car isn't using any gas at all. But like a pure-electric car, once a driver steps on the "gas" pedal, the electric engine comes to life and instantly propels the car forward.


Here is a video i presented in class and it shows the new and futur of BMW .
Must Watch Good Video.

References

http://www.automotiveaddicts.com/6646/bmw-vision-efficientdynamics-concept-video-revealed
http://abcnews.go.com/Technology/Hybrid/story?id=97518&page=1
http://www.fueleconomy.gov/feg/hybridtech.shtml

Oxygen sensor Circuit Post 3:

Oxygen sensor circuit:

The task we had to was to build a oxygen sensor using the flowing components.thses components have to be put in all together to build the circuit

12v Battery
3 LED's:
1x Red led
1x Yellow led
1x Green led
1x Op Amp  LM324
3 diodes 1N4001
7 resistors (R2=1KΩ, R3=1KΩ, R4=1KΩ, R5=380Ω, R6=10KΩ, R7=270Ω, R8=470Ω)
1 zener diode 9v1
2 capacitors  0.1uF




Calculation:


R2, R3 & R4
I= 9.5mA =0.0095A
The voltage drop in R2 is at 9.6v, Vd=12 - 0.6 - 1.8 =9.6v
R=V/I =9.6/0.0095 =1010.5Ω
The voltage drop in R3 is at 9v, Vd=12 - 0.6 - 0.6 - 1.8 =9v
R=V/I =9.6/0.0095 =947Ω
The voltage drop in R4 is at 9.6v, Vd=12 - 0.6 - 1.8 =9.6v
R=V/I =9.6/0.0095 =1010.5Ω


R5=
Power supply voltage is at 12v, Vd of crossing diode D2=0.6v, Vd of zener diode D1=9.1v
Vd of R5 = 12-0.6-9.1= 2.3v
I=5.6mA=0.0056A
R=V/I =2.3/0.0056 =411Ω


R7 an R8


R6=10KΩ Voltage drop in crossing R6 is at 8.47v 
The volage are at 9.1v and 0.63v before the R6 and after the R6 each. 
So, Vd=9.1-0.63 = 8.47v
ohms law I=V/R =8.47/10,000 =0.000847A


R8=
VD= 0.4
Vd= 0.63 - 0.23 =0.4v
R=V/I =0.4/0.000847 =472Ω
R7 consumes the voltage which voltage drop is at 0.23
Vd= 0.23 - 0 =0.23Ω
R=V/I =0.23/0.000847 =271.5Ω
Total resistance RT=R6+R8+R7 =10,743Ω
I=9.1/10,743 =0.000847A


The calculation is shown in the diagram blew please click on the image to view it larger as it might be harder to see.

here is picture of it after i built on breed board .

I also recored a short clip it showing how its working for example when its running lean or when its running richer or when its in between and this had be also on breed board .

Here is some pictures after i built it on pcb board it shows the emission of how the car is running it has 3 different color LEDs so they represent when the car is running lean or when its rich or when its in between

                                                  The LED shows when its Rich mixture

                                         The yellow LED shows whens its running in normal mixture

                                            And the green LED shows that when its running in lean mixture

                                           The is the picture of my oxygen sensor

And here is the video clip i recored when i finshd building and then i connected to check if its working and here is the video you can see it your self to its working fine.

Oxygen sensor

Since oxygen sensor mainly control the fuel mixture of the engine by measuring the oxygen content parameter for the engine computer (ecm), it is necessary for us to understand how this sensor circuits works.

In the early 1980s when oxygen sensor was first introduced, it has only one signal wire. This sensitive wire was designed so that it only takes low voltage signal under 1 volt. This crude design has a major flaw; it takes too much time for the sensor to give signal to the engine computer.

It is the computer’s job to regulate the fuel mixture after the sensor warms up which sometimes takes about 10-15 minutes. This time delay can gets worse when the weather gets cold and would dump a lot of raw fuel to the catalytic converter (CAT). This leads to premature CAT failure and high fuel .But since 1994 to 2006 the oxygen sensor has been upgraded to solve this problem.

The O2 sensor is mounted in the exhaust manifold to monitor how much unburned oxygen is in the exhaust as the exhaust exits the engine. Monitoring oxygen levels in the exhaust is a way of gauging the fuel mixture. It tells the computer if the fuel mixture is burning rich (less oxygen) or lean (more oxygen).

Reference

http://blog.automotivetroubleshootingsecrets.com/hho-gas-tips/fix-oxygen-sensor/

ilyas injector circuit. blog2

The project for today was to build components to a PCB board to make the LED turn on the voltage is supplied to the base of the transistor . this makes the LED light up and also indicates when the fuel injector is firing .

A components list


The things i needed to build my injector circuit was 2 transistor 4 resistor, 2 LED lights and board. and some wires .i took some pictures and a video clip to show how its working .
2 NPN BC547 transistors, and two LED's. Then we had to wire up the components on a bread board to make sure that the circuit works and that we get to practice and get better at it before we build the real circuit and to show up how to wire up the components on the PCB board. we used the resistor calculation to make sure that the all the components were getting the right amperage to make the LED and transistor work correctly 
we used to data sheet to find out the correct resistor that we could use .

Thats the video clip i took once i built the circuit board it shows how its working at low frequency and high frequency.

I also built my board on lochmaster its a software that lets you built any sort of circuit board that you want and the one i built i took some pictures of it which is below.


Ohms law
Ohm's lawThe current flow through a Resistance there must be a voltage across that resistance. Ohm's law shows the relationship between the voltage current  and resistance.


Kirchhoff's Law:
Kirchhoff's Law says that the voltage supplied to a circuit is used within the circuit before it goes back to the power source. Voltage supplied = Voltage used by the circuit.

12-1.8-0.2= 10 v

R= V/ I

R 10 / 0.2(20ma)

R= 500 ohms

specs transistor

Ic = 100 ma (max)

vce = 45v (max)

vcb = 50 v (max)

vbe = 6v (max)

R = V/ I

R = 4.4 / 0.004

R = 1K100

Blew is a video clip of my PCB board i recored it when i finshed building it to check it and make sure that its working the way it should be anyways here it is.

heres pics of my injector board 

LchMaster:

We had to use lochmaster to build our board on there first to make sure it working the way it should be and to to make sure the right amount voltage is supplied etc.. once we done that we get to show it to our teacher to make sure its working fine after that we were allowed to build it on PCB board.
LochMaster is a developers tool for strip board projects. It has useful functions for designing, documenting and testing a board. Therefore you will find features like auto-generation of components lists, a connection test, an editable library with a large number of symbols and components, and many more.The newer the version software the more features it will have because the they always come with newer version so its good to get it updated.

here a link to Lochmaster where you can download a demo.
http://www.abacom-online.de/uk/html/lochmaster.html


Transistors:

How do transistors work?
Transistors stop and start the flow of an electrical current, and they also control the amount of current. The first transistors were made of germanium, which is a good insulator. Scientists "doped" (added impurities to) the germanium, making it into a weak conductor, or a semiconductor. Depending on what was used to dope the germanium, the semiconductor was either N-type (negative) or P-type (positive). An N-type semiconductor lets electrons flow out of the germanium, and a P-type lets electrons flow into the germanium. When an N-type semiconductor is put near a P-type semiconductor, you have a P-N diode, which lets electricity to flow in one direction. If two semiconductors are placed either in an N-P-N pattern or a P-N-P pattern, you have a junction transistor. The junction transistor's center layer is the base. If electricity is applied to the base, electrons start moving slowly from the N side to the P side. As more electrons change sides, their speed picks up. Thus the transistors function as both the switch and the amplifier, allowing control of the amount of electricity flowing through the circuit board.

What is a resistor and how does it work?

The more resistance a thing has, the more it limits current (at a given voltage). In a circuit, resistance and current are inversely proportional. The more the resistance, the more current will be limited and the less current will actually flow. Resistors pay a price for limiting current - they create heat.


A resistor partially conducts current flow, but it heats up as a consequence to having current forced through it by some applied voltage.




Reference
http://www.ehow.com/video_4977215_transistors-work.html
http://curiosity.discovery.com/question/how-do-transistors-work
http://talkingelectronics.com/projects/OP-AMP/OP-AMP-1.html
Moodle
http://www.wisc-online.com/objects/ViewObject.aspx?ID=SSE3603

TTEC 4824 – AUTOMOTIVE ELECTRONICS

EXPERIMENT No. 1

Identifying, Testing and Troubleshooting Semiconductor Components.

 Identifying, Testing and Combining Resistors.

• First two or three bands may be the numbers to write down
• Next band is the multiplier (how many zeros to add to the number)
• Gold multiplier makes one decimal place smaller, Silver makes two decimal places smaller
• Last band to right may be tolerance values
• Notice the examples on the right
• Brown, red, red = 1, 2, 100, 5% = 1200Ω 5%, or 1.2KΩ,1K2

Obtain 6 resistors of different values.  You are then going to determine their value two ways: 

·         Use the colour code to calculate the value of the resistor.

·         Include the maximum and minimum tolerance value of each resistor

·         Then measure the resistor value with a multimeter.

Record the values in the chart below.

Value (colour codes )	Value (multimeter)
10000 times 0.05= 95 to 105	9.95 K ohms
5600 times 0.05 =280 - 5320      + 5880	5.54 K ohms
4700 times 0.01 = 47 +4747       - 4653	472.1 K ohms
100000 times 0.05 =5000 - 95000   + 105000	99.3 K ohms
270 times 0.05 = 13.5 +283.5      -256.5	268.8 K ohms
100 times 0.05 =5 -95   + 105	98.9 K ohms

Choose two resistors and record their individual ohm resistance value measured with a multi-meter:

            Resistor 1. 269.1  Ω       Resistor 2. 471.9 Ω

Put these two resistors together in series (end to end, one right after another) calculate and then measure their combined value. Show workings:

Calculated value 1 and 2 in series: 741.7 Ω         RT=R1 +R2

Measured value 1 and 2 in series: 739.00 Ω

Put these two resistors together in parallel (connect both ends when they are side-by-side). Calculate and then measure their combined value. Show workings:

Calculated value 1 and 2 in parallel: 171.3  Ω    1over RT = 1  over R1 + 1 over R2

Measured value 1 and 2 in parallel: 171.3  Ω     

What principles of electricity have you demonstrated with this? Explain:

When resistors are connected in series the resistor values are just added together.

This circuit shows RT = R1 +R2 formula with its principles .

As a results total resistor values increases however in parallel circuit which uses R1 over RT= 

1 over R1 + 1 over R2 formula and total resistance value is low than the lowest resistor value .

EXPERIMENT No. 2

Components: 1 x diode, 1 x LED

Exercise: Using a multimeter, identify the anode and cathode of the diode and the LED.

	Voltage drop in forward Biased Direction.	Voltage drop in reverse biased direction
LED	1.784 v	0v
Diode	0.568	0v

Explain how you could identify the cathode without a multimeter.


On LED the cathode side is smaller then the anode .and also there is
small edge cut off that represents the cathode side.
On diode the grey band represents the negative which is the cathode and some cases you cant find it...

Table 1: Data sheet of 1N4007 is as follows

Absolute Maximum Ratings, TA = 25OC
Symbol	Parameter	Value	Units
IO	Average rectified current @ TA = 75oC	1.0	A
PD	Total device dissipation Derate above 25oC	2.5 20	W mW/OC
	Thermal resistance, Junction to Ambient	50	OC/W
	Storage Temperature Range	-55 to + 175	OC
	Operating Temperature Range	-55 to + 150	OC
VRRM  (PIV)	Peak repetitive reverse voltage	1000	V

Components: 1 x resistor, 1 x diode. 1 x LED

Exercise: For Vs=5V, R= 1KΩ, D= 1N4007 build the following circuit on a breadboard.

Calculate first the value of current flowing through the diode, now measure and check your answer?

Calculated : I = V/R

I = 5/1000 omhs = o.005 A

Measured: 0.0055ma

Is the reading as you expected; explain why or why not?

Yes the reading we got is the same as expected because we calculated.

in series current flows one way throughout the circuit

and it also stays the same .

What is the maximum value of the current that can flow through the given diode?

Average rectified at TA = 75* a.00 A

For R = 1KΩ.  What is the maximum value of Vs so that the diode operates in a safe region?

peak repetitive reverse voltage 1000V

Replace the diode by an LED & calculate the current, then measure and check your answer?

calculated I = V/R     measured 0.003 A

What do you observe? Explain briefly.

The current changes a little due to different voltage drop of the components

when we have LED connected we have around 0.003A in the circuit

when the diode has less voltage drop then the current is a little bit higher.

EXPERIMENT No. 3

Components: 2 x resistors, 1 x 5V1 400mW Zener diode (Z_D).

For R= 100Ω and RL= 100Ω, Vs= 12 V.

What is the value of Vz?

VZ= 4.96v

Vary Vs from 10V to 15 V:  10V = 4.77v   15V= 3.06V

What is the value of Vz: VZ = 4.77V  VZ = 5.06 V

Explain what is happening here.

At low the value of VZ is 4.77 and as is increase the Vs to 15 the value of the vz

is 5.06V because there is more vs.

The voltage is staying at around 5v regardless of the supply voltage

increasing this is because the diode is acting as a regulator because 

it is in reverse bios.

What could this circuit be used for?

Dis piking protection and stable voltage

EXPERIMENT No. 4

Components: 1 x resistors, 1 x 5V1 400mW Zener diode, 1X Diode1N4007 .

Exercise: Obtain a breadboard, suitable components from your tutor and build the following circuit.

                Vs=10 & 15v, R=1K ohms

10 Volts


Volt drop v1: 4.6vd
volt drop v2: 0.69vd
volt drop V3: 5.29vd
volt drop v4: 5.24vd
calculated current A: i =10v/1000 ohms = 0.01
i= V/R


15 volts
volt drop v1: 9.68 vd
volt drop v2: 5.74 vd
volt drop v3: 0.69vd
volt drop v4: 4.77vd
calculated current A: i = 15/1000 = 0.015 A

Describe what is happening and why you are getting these readings:

V4 value is changed at 9.5v under 15 v however the v1,v2 and v3 values are

similer between 10v and 15 volts because the Zener diode keeps 3 volts and 

block less 5v.so the v4 of the resistor only changed.

The current value is at 0.01A all areas due to this circuit is connected in series.

EXPERIMENT No. 5

   

The Capacitor

The capacitor stores electric charge.

A capacitor consists of two metal plates very close together, separated by an insulator. When connected to a battery or power source electrons flow into the negative plates and charge up the capacitor. The charge remains there when the battery is removed. The charge stored depends on the “size” or capacitance of the capacitor, which is measured on Farads (F). 

Identifying Capacitor “Size”

If the Farad “size” is not printed on the capacitor, you may find an EIA code listed. Use the table below to figure out the capacitance

μF	nF	pF	EIA Code
0.00001*	0.01	10	100
0.0001*	0.1	100	101
0.001	1.0 (1n0)	1,000	102
0.01	10	10,000*	103
0.1	100	100,000*	104
1.0	1000*	1,000,00*	105
10.0	10,000*	10,000,00*	106

RC Time Delay or “Charging Time”

Capacitors take time to charge. It doesn’t happen instantly. The charge time is dependent on the resistor in the circuit and the size of the capacitor. And it is expressed in the equation: R x C x 5 = T.  This is the time it takes to charge up to the applied voltage.

For example, 1,000,000 Ω x 0.000001 F x 5 = 5 seconds to charge to applied voltage. This can also be expressed as 1 MΩ x 1 μF x 5 = 5 seconds.

Capacitors are often used for timing when events take place. And often the voltage only has to get up to about 2/3 the applied voltage, and this happens at about 1/5 the time of their charging. So this is why the 5 is built into the equation. The concept of “time constants” is used here, where whatever the time it takes for a capacitor to build up to the full charge, it takes about 1/5 of that time to build up close to 2/3 of the charge. So you can divide the charge time into 5 segments, and the first time segment is often the time you are interested in.

Fig 8-Capacitor Charging Circuit

Components: 1 x resistor, 1 x capacitor. 1 x pushbutton N/O switch.

Exercise: First, calculate how much time it would take to charge up the capacitor. Then, connect the circuit as shown above. Measure the time taken by the capacitor to reach the applied voltage on an oscilloscope. Fill in the chart below. Also draw the observed waveforms in the graphs below, filling the details on each one.

Note: you will need to adjust the time base to enable you to observe the pattern.

Circuit number	Capacitance (uF)	Resistance (KΩ)	Calculated Time (ms)	Observed Time (ms)
1	100	1	500
2	100	0.1	50
3	100	0.47	253
4	330	1	1650

  

capcaitance 100uf           Resistance: 1k ohms

Capacitance: 100 uF             Resistance: 0.1k ohms

Capactance : 100uF                Resistance: 0.47 k ohms

Capacitance: 330uF          Resistance 1K ohms

How does changes in the resistor affect the charging time?

The lower the resistance the more current getting through 

Therefore quicker the charge time.

How does changes in the capacitor affect the charging time?

The more capacitance of the capaitor the more charge it can hold

therefore longer time it will take to charge up.

EXPERIMENT No. 6

Identify the legs of your transistor with a multimeter. For identifying and testing purposes, refer to the representation shown above.

Diode test (V) meter readings
Transistor number	VBE	VEB	VBC	VCB	VCE	VEC
NPN	0.719	0.718	0.L	0.715	0.L	0.L
PNP	0.683	0.L	0.68	0.L	0.L	0.L

 Emitter has slightly higher voltage then the collector.

EXPERIMENT No. 7

Transistor as a switch

Components: 1 x Small Signal NPN transistor, 2 resistors.

Exercise:  Connect the circuit as shown in Fig 12 and switch on the power supply.

Connect the multimeter between base and emitter.

Note the voltage reading and explain what this reading is indicating.

0.798 volts,This reading shows that the current is flowing from the base to the emitter

This means that the transistor is turned on and the current should 

be flowing from the collector to the emitter.

Connect the multimeter between base and emitter.

Note the voltage reading and explain what this reading is indicating.

0.054 volte (VD) This reading shows thr voltage drop across the transistor

from thr collector to the emitter. this also shows that the

transistor is fully open or saturated and minimal voltage is required to

allow current to flow through the transistor.

In the plot given below what are the regions indicated by the arrows A & B?

How does a transistor work in these regions? Explain in detail:

This graph shows that all the area marked with A is the area when the transistor

is fully turned on or saturated this mean that no voltage is required to push

current through from the collector to the emitter .

Area B is the area where the transistor is off there is no current flowing from 

the base to the emitter so no current can flow from the collector to the emitter.

What is the power dissipated by the transistor at Vce of 3 volts?

pd = p = v x i = 3 x 0.013 = 0.039 watts

What is the Beta of this transistor at Vce 2,3 & 4 volts?

Beta = gain      B = 1/IB (base current)

2 volts = 21 /0.75 = 28

3volts = 14 / 0.5 = 28

4 volts = 7 / 0.2 = 35

EXPERIMENT No. 8

Summary: Vary the base resistor and measure changes in voltage and current for Vce, Vbe, Ic, and Ib. Then plot a load line.

Set up the following circuit on a bread board. Use a 470R for Rc and a BC547 NPN transistor.

Pick five resistors between 2K2 and 1M for Rb. You want a range of resistors that allow you to see Vce when the transistor is the saturated switch region and when it is in the active amplifier region. I used 47K, 220K, 270K, 330K and 1M, but this can vary depending on your transistor. Some may need to use 2K2. Put one resistor in place, and measure and record voltage drop across Vce and Vbe. Also measure and record the current for Ic and Ib. Then change the Rb resistor and do all the measurements and record the new readings. Do this for each of the resistor values above.

  Record here:

Rb 4.39v        Vbe 0.696v      Vce 0.697v      Ib 21.1 ua        Ic 5.37mA

Rb 4.689v       Vbe: 0.754v      Vce: 47.4mv      Ib: 461.6ua         Ic: 6.92mA

Rb 4.821v       Vbe: 0.668v      Vce: 2.444v      Ib: 8.3uA         Ic: 2.16mA

Rb 4.635v       Vbe: 0.757v      Vce: 43.7mv      Ib:562uA       Ic: 6.65mA

Rb 4.716     Vbe: 0.673v  Vce:2.217v  Ib:10uA        Ic:2.60mA

Your voltage drop measurements across Vce should vary from below 0.3 v (showing the transistor is in the saturated switch region) to above 2.0 v (showing the transistor is in the active amplifier region) If this is not the case, you may have to try a smaller or bigger resistor at Rb. Talk to your teacher to get a different size resistor, and redo your measurements.

 Discuss what happened for Vce during this experiment. What change took place, and what caused the change?  

The different resistance of the Rb meant there was more or less amperage flowing

from thr base to the emitter this will mean that the resistor is more of less

saturated or turned on .Although voltage from the base to the emitter is roughly the same 

it is the amperage that determins how well the transistor is turned on and

how big or small of voltage drop the will be from the collector  to the emitter.

Discuss what happened for Vbe during this experiment. What change took place if any, and what caused the change?

The voltage from the base to the emitter does not change too much as the control side

of the transistor only requires 0.6 - 0.7 volts switch on high power sides of the transistor from the collector to the emitter.

Discuss what happened for Ib during this experiment. What change took place, and what caused the change?

Current flow at base was affected by the transistor used if there was a large resistor 

i.e higher resistance to current flow then current flow is reduced . 

If smaller resistor used with less resistance to current flow then current flow is higher as 

it easier for current to flow.

 Discuss what happened for Ic during this experiment. What change took place, and what caused the change?

The resistors that changed at Rb meant there was more or less restriction to the current flow

through the circuit,this in turn affected how much current would flow

through the collector to the emitter.

Plot the points for Ic and Vce on the graph below to create a load line. Plan the values for so you use up the graph space.  Use Ic as your vertical value, and Vce as your horizontal value.

Using Vbe on the Vce scale, plot the values of Ib so the finished graph looks similar to fig 13

Calculate the Beta (Hfe) of this transitor using the above graph.

B=ic/iB

 Explain what the load line graph is telling you. Discuss the regions of the graph where the transistor is Saturated, Cut-off, or in the Active area. 

The load line is telling us the relationship between current to the collector (IC)

and voltage drop from thr collector to the emitter.

(VCE) This can tell you when the transistor is fully saturated or turned on as the line

will show high current flow from the base to emitter meaning the transistor

is more turned on so there is small voltage drop which seen at VCE.

Reference
Google images
Unitec moodle
Google