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# ELECTRONICS STUDENTS QUESTIONS

If you are a student in electronics or a professional in electronics, we encourage you to be a part of our FORUM.  Ask questions.  Get help from others or just see what is going on.  Let's have some fun while we are learning.

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You can find a wide variety of circuit symbols at the following website. http://www.kpsec.freeuk.com/symbol.htm

Ohm’s law is very powerful.
You should know the three forms of Ohm’s law.
V=IR
I=V/R
R=V/I

This is how I learned to remember the resistor color code:

Boys      Brown 1

Rape      Red 2

Our        Orange 3

Young    Yellow 4

Girls       Green 5

But         Blue 6

Violet      Violet 7

Gives      Gray 8

Willingly  White 9

If you have another way or a better way, please share.

Can you solve it?

How was your Lab Final?  Did you have questions about it?  Let me know and I will try to help.

# Car LED Light Sequencer Project

Introduction To Car LED Light Sequencer

This Car LED Light Sequencer uses a standard 74C164 8 bit shift register as its heart of operation. The 74C164 is also known as a 8-Bit Parallel-Out Serial Shift Register which is a monolithic complementary MOS (CMOS) integrated circuit. These 8-bit shift registers have gated serial inputs and clear. Each register bit is a D-type master/slave flip-flop.

Data is serially shifted in and out of the 8-bit register during the positive going transition of clock pulse. Clear is independent of the clock and accomplished by a low level at the clear input. It has a wide supply voltage range from 3V to 15V DC.

The connection pin layout and truth table of the 74C164 IC is as shown below.

Circuit Description

The input data goes to the serial inputs at pin 1 and 2 which are connected to VCC of the circuit. When pins 1 and 2 are high, the data moves one step forward with each clock pulse. As shown in the diagram above, the outputs are pins 3-6 and 10-13. The data flows from output 1 to 2 to 3... to 8 with each positive edge of the clock pulse. The data can be cleared to zero by putting a momentary low input at pin 9.

The schematic diagram below shows the car LED light project. It can be adapted and used for any other projects that one can think of.

Two gates of 4011 quad two input NAND gate IC2-a and IC2-b are connected as an astable oscillator circuit with the frequency of operation set by C1 and R11. The clock's positive output pulses at pin 4 of IC2 are connected to the clock input of 74C164.

An LED with a resistor of 1K each is connected to the outputs of the shift register. The shift register's 8th output atpin 13 is connected through a RC network delay circuit of R10 and C3. When the 8th clock pulse turns on LED8, pin 13 of IC1 goes positive, charging C3. After a period of time, IC2-c output goes low clearing the shift register outputs.

The first clock pulse turns LED1 on, the second LED2, the third LED3 until all eight of the LEDs are lighted ON. After the8th LED turns ON, the clear pulse from IC2-c turns OFF all the LEDs and the sequence is repeated.

The values of R10 and C3 may be varied to allow LED8 to remain ON for the same time period as each of the other LEDs.The RC time delay circuit will need to be shorter for a faster sequence by decresing the R10 or C3 and vice versa.

Car LED Light Parts List

The parts list of the project is as shown below.

This is finals week at ITT Technical Institute.  If there are any electronics students who need some help preparing for their final exam, check here in our FORUM.  You can help each other.  Also you can get help from me, Mr. Trent and from Mr. Fearrington who will be on the FORUM soon.  Good luck to you on your final exams.

I agree the students should take advantage of posting questions about course material or even questions concerning where the industry is headed.

Jerome Trent said:

You can find a wide variety of circuit symbols at the following website. http://www.kpsec.freeuk.com/symbol.htm

 Electronics Tech Students Work with Holograms Electronics Technology Class of 2012 students got the chance to work with holograms.Holograms are 3-D images that have been projected and captured on a 2-D surface. Judy Donnelly from Three Rivers Community College visited Windham Tech to help the Electronics Tech students about holograms which are made with a red laser and photo glass. The Electronics Tech program made a make shift dark room in shop then placed an object under the photo glass and exposed it by shining the red laser down thru the glass. The glass was then developed like black and white film. Once the glass is dry they spray painted the back black so that the image shows up better. It was a great opportunity for students to work with technology that will only become more advanced and more important in the future.Connecicut Technical High School System

How about those final exams.  Were they tough or what?  Do you remember a tricky question on your exam?  Share it with us.  Let's figure out what the correct answer should be.

Electrical Transformer Tutorial from youtube helps you to understand transformers and how to select an appropriate transformer for your power supply.