Elenco's PK-201 Experiment #2: The Brightness Control

In this experiment the focus is understanding the Variable Resistor (0 to 50k ohm). A device that has three pins (terminals to run electrical current through) and a dial. The dial is for increasing or decreasing resistance. When the dial is set to a minimum, the resistance is 0 ohms. Turn the dial to maximum then the resistance is set to 50k ohms. In the pictures, the Variable Resistor is wired from the center pin to left pin, center pin to right pin, or left pin to right pin. This means, depending on how the Variable Resistor is wired, that the resistance is measured between two of the three pins (left to center, right to center, or left to right). In the picture left to right, the resistance is between the left and center post. By turning the Variable Resistor to the right, one would increase the resistance hence dimming the light. In the picture right to left, the resistance is from right to center. By turning the resistance to the left, one would increase the resistance hence dimming the light. In the last picture, the resistance is 50k ohms. This is because the wiring is from left post to right post causing a lose of the variable attribute.

High Resistance (Left to Right)

Low Resistance (Left to Right)

High Resistance (Right to Left)

Low Resistance (Right to Left)



Full Resistance (None Variable)

 

 

Info on resistors

Elenco's PK-201 Experiment #1: The Light Bulb

This experiment teaches how changing resistance in a circuit can increase or decrease the current passing through it.

10k ohm resistor

1k ohm resistor

100k ohm resistor

Signal Generator by Velleman

The Signal Generator by Velleman can be used to produce four different signal waveforms: sine, triangle, square, and integrator. The signal frequency is fixed at 1kHz and output level is adjustable via a potentiometer (0 to 100mVrms). Signal waveforms are a variation of voltage over time. A Signal Generator is used for testing and repairing electronic devices. In addition, Signal Generators may be used in prototyping a circuit. More over, in computer architecture, a waveform that switches between two voltage levels represent two states of a value 0 and 1.   

Signal Generator

Sine

Square
 

Integrator



Triangular

 

 Further Study:

AC Theory

Electrical Signal Types

Electrical Waveforms

What is a Signal Generator



Elenco's Sound Reversing Car

The Elenco Sound Reversing Car is a voice controlled robot car. The car is made up of transistors, capacitors, and resisters. In addition, a microphone and a few mechanical parts. The car will move forward until a sound is detected then the car moves backwards to the left for about two seconds before moving forward again. The two major components of the car are a microphone and a 15 degree pivoting front wheel, which position is dependent on the current direction of the car.

Sound Reversing Car



Front



Top




Finished Printed Circuit Board



Gear Box and PCB

Below is the movement of the front wheel.

 



K7000 Signal Tracer / Injector Kit by Velleman

 

 The K7000 signal tracer is a sine wave generator. A signal tracer can be used to inject a signal into a circuit to find a fault or locate a defective component. Commonly used with an audio circuit, such as, amplifiers, radios, musical instrument pickups, and speakers.

 

 

K7000

 

 

Sine wave on the oscilloscope



 

 

General Information:

Signal Tracer

DIY 062 Oscilloscope by JYE Tech

 

I enjoyed assembling the Do It Yourself 062 Oscilloscope kit by jyetech. The surface mount components came pre-soldered. I soldered the through-hole components. I found, I had to use magnification to solder the through-hole components. The probe was easy to assemble. I had never assembled a probe before, and I learned that the plug's core is always positive on the connector end. Later, I upgraded to a BNC probe kit. I had to install a BNC connector and remove the old installed connector. Oscilloscopes are used in science, engineering, medicine, and telecommunication. The oscilloscope is a tool used to measure voltage and frequency of an electrical signal.

 

 

Assembled
 

Startup
 




Home made probe test



BNC connector
 

BNC probe test

 

062 Digital Storage Oscilloscope DIY Kit
JYE Tech Products

 

 

IR Light Barrier by Velleman

This is the Velleman IR Light Barrier. A IR transmitter and IR receiver. The IR receiver detects the absents of IR light, buzzing to give notice. Watch the video staring my father.



IR Transmitter and Receiver
 

Infrared Light is visible through a digital camera
 

 

Further Study:

Infrared Light Information

Infrared Light Signals