delabs Circuits

Wednesday, April 30, 2008

Historical Electricity Teaching Instruments

In February 1975, Deborah Jean Warner, a Curator of Physical Science at the National Museum of American History, called me to ask if Kenyon had any historical physics teaching apparatus. I looked around my office.......

Thomas B. Greenslade, Jr. - Professor Emeritus of Physics - Kenyon College, Gambier, Ohio

Historical Electricity Teaching Instruments

Electrical Measurements, Electric Motors, Electricity, Static Electricity.

Historical Electricity Teaching Instruments

Physics apparatus often goes by various names. The interrupter, the electrotome and the repeater are all the same instrument. Some apparatus has a person's name attached to it: Matteucci's apparatus or Wheatstone's bridge. Other apparatus isn't used any more: Packard's apparatus or the piezeometer.

LED brightness controler - Jaroslav Belza

LED brightness controler - Jaroslav Belza

White LED lantern powered from USB port. Jaroslav Belza

delabs Notes-

R1 Limits the LED current when T1 is fully Turned on or saturated. P1 forms a Variable Potential Divider, The Turning of P1 Pot gives a 0 - 5 V Variable Voltage Proportional to the turning, if it is a Linear Pot.(Audio Systems use a Log Pot as the Ear Hearing response to sound is Non-Linear.). As the impedance of this Voltage source is a bit high, it is from a 5K pot, it cannot be loaded with a low value resistor like 100E or 1K.

The R1 should limit the current to an optimum value in relation to LED Brightness vs. Battery Life. T1 chosen must have a Max Ic of at least Five times the LED current, for a long lasting product.

R2 you can figure out from the beta of the transistor. That you can learn at Transistor Operation - HyperPhysics.

Tuesday, April 22, 2008

VU Meter Circuits and Projects

Here is a collection of web pages of VU Meter projects that helps a newbie getting into the Electronics DIY Hobby Land.
VU Meter Circuits and Projects

A Hobby now in your School days or College can help you build a strong profession later. It is Edutainment that will make productive use of your spare time. Friends can do it as a group, during holidays. Parents should encourage healthy hobbies, as the children will grow in a positive and creative atmosphere.
Stereo Vu Meter Kit

This is a very eye appealing audio accessory. Displays an approximate output level for each channel of a stereo amplifier. Connects to the speaker terminal; levels are displayed in ten steps. User may select either a moving dot bar appearance. Uses two LM3915 IC's; includes a discussion of measuring audio power.

Saturday, April 19, 2008

The Scots Guide to Electronics

This course is designed to help you learn about components, circuits, and the use of electronics. You can explore the contents in whatever order you wish.The emphasis is on providing information starting at the 'absolute beginners' level, but we hope eventually to provide material of use to anyone interested in electronics and its applications ...

The Scots Guide to Electronics

This section of the Scots Guide deals with Analogue Electronics with a special emphasis on Audio-related topics. There are also some specialist pages on the properties of cables as these relate to audio.

The Scots Guide to Electronics

The First Eleven - Basic electronics courses sometimes make it appear as if electronic engineers have an obsession with voltmeters, batteries, and oscilloscopes. That's because it's often convenient to talk about these when presenting a course at a university, college, or wherever. In reality, the physics and electronics of practical systems like Hi-Fi's, TV's, computers, etc, are much more interesting.

The main components used in electronics are of two general types: passive (e.g. resistors and capacitors) and active (e.g. transistors and integrated circuits). The main difference between active and passive components is that active ones require to be powered in some way to make them work. Active components can also be used to amplify signals.

by J. C. G. Lesurf University of St Andrews Astronomy Group, Scotland.

Category Engineering - Wikibooks

This category contains a number of subcategories, books, and pages related to Electrical engineering. Books can be found on the Engineering EE. Courses can be found at Wikiversity:School of Engineering.

Subcategories include specific engineering disciplines, including Electrical Engineering, Computer Engineering, Mechanical Engineering, and Civil Engineering. Also, some books that are general to all disciplines are listed here.

Digital-to-analog converter

A DAC converts an abstract finite-precision number (usually a fixed-point binary number) into a physical quantity (e.g., a voltage or a pressure). In particular, DACs are often used to convert finite-precision time series data to a continually varying physical signal.

Digital-to-analog converter

Analog and Digital Conversion, Automatic Control Engineering, Automotive Systems. Basic Electrical Generation, Basic Electricity, Biography of Nikola Tesla.

Circuit Idea, Circuit Theory, Communication Systems, Control Systems. Digital Circuits, Digital Signal Processing, Electronics, Embedded Control Systems Design

Embedded Systems, Practical Electronics, Power Systems Analysis, Design, and Control Microprocessor Design, Engineering Tables, Semiconductors, SensorNetworks

Friday, April 18, 2008

School of Analog Design

School of Analog Design

Switching Regulator Fundamentals
Objective: Be able to identify the three basic switching regulator configurations and know where each one is used. The course includes inductive switching regulator power stage definition, input, output and duty cycle relationships.

Current Feedback Operational Amplifier
Objective: This training module discusses the current feedback operational amplifier (CFB op amp). There will be a brief background of the current feedback op amp.

DC to DC Converter Basics
Objective: This course will teach the basics of linear, inductive, switched capacitor DC to DC converter products from Portable Power Systems perspective.

Thursday, April 17, 2008

Science Toys - Edutainment at Home

Make toys at home with common household materials, often in only a few minutes, that demonstrate fascinating scientific principles. See also the Science Blog, - Creator - Simon Field

Science Toys - Edutainment at Home

This Website is a valuable resource for students to learn basics and get interested in electronics and computers - delabs

Science Toys - Edutainment at Home

Electromagnetism: - An electric motor in 10 minutes

The motor is simply a battery, a magnet, and a small coil of wire you make yourself. There is a secret to making it (which I will of course share with you) which is at the same time clever and delightfully simple.

Other Projects - Fun with High Voltage, A 10 minute railgun, A 30 second motor.
    Radio: A quick and simple radio

    The reason a crystal radio does not need any batteries is the amazing capabilities of the human ear. The ear is extremely sensitive to very faint sounds. The crystal radio uses only the energy of the radio waves sent by radio transmitters.

    Others are Building a radio in 10 minutes, Build a portable crystal radio, A radio out of household items, A simple AM transmitter, The Three-Penny Radio.
      Computers and Electronics: A Computer Controlled Transmitter

      In this project we will build a very simple radio transmitter that you attach to a serial port on your computer. The computer then runs a free program that converts words you type into radio signals that are decoded by another computer, using a cheap radio receiver, and a sound card.

      More - A Free Space Laser Data Transmitter, Fun With Solderless Breadboards, A Simple 1 Watt Amplifier

        Friday, April 11, 2008

        Electronics Club

        Electronics Club

        Example Projects, Construction of Projects, Soldering Guide, Study Electronics, Electronic Components, 555 Timer, Circuit Symbols.
        • Example Projects
        • Construction of Projects
        • Soldering Guide
        • Study Electronics
        • Electronic Components
        • Circuit Symbols
        John Hewes, Kelsey Park Sports College.

        (This is good place to start your electronics study, it has a practical and simple Approach - delabs)

        Product Design Precautions

        When you design a new Product or Engineer an existing one; communications and documentation is important. Creating a satisfying solution is the main thing. If requirements and specs or not properly developed it can lead to blame-games, wasted time and spoils the reputation.

        A firm also should do proper market study before the decision to design a product. Even a well designed product cannot be sold if it does not offer a cost-effective solution.

        Black Box Specifications

        Product Design Precautions
        • Start Projekt {
        • Customer Interaction and Communication to make a specs sheet and drawing.
        • Block Diagram, feasibility, cost, risk, samples demo and study similar ideas.
        • Effective designs are cost effective within customer budget, draft BOM costing.
        • Circuit and Code design and get more inputs from customer and then freeze specs.
        • Build Dummy for ergonomics and discuss, Prototype and start test at site or simulate.
        • Calibration and testing and production documentation drafts final costs.
        • Pilot Production of a small batch, rigorous test batch, and freeze production documents.
        • Documents and Prototypes to be given to Production Engineering.
        • Production Engineering continue engineering maintenance and quality issues.
        • } End Projekt

          GoTo Next Projekt
        (I had written this in Aug-05, it is my 90s experience, it may indicate some useful points - delabs)

        Monday, April 07, 2008

        Edison Phonograph

        Thomas Alva Edison
        From Soldermans Basic Electronics

        Miami Museum of Science - The Atoms Family

        This resource contains educational activities about energy concepts, the power of the sun, energy conservation, energy transformation, electricity and fossil fuels being presented by famous gothic horror characters.

        Miami Museum of Science - The Atoms Family

        Electrical Safety - Static Electricity - Fruity Electricity.

        Miami Museum of Science - The Atoms Family

        Flying a kite near any kind of overhead wires is VERY DANGEROUS! The overhead wires could shock the kite, the electricity would then travel down the kite's string and shock you!

        Atoms Family - Frankenstein Lightning Lab

        Only electrical plugs should be put into electrical outlets. Never place anything else into an electrical socket, it may shock you or start a fire!

        Lamps use electricity to make light and can get very hot! If things get to close to a hot lamp they can catch on fire!

        Hair dryers and water don't mix, and can be very dangerous! Never use a hair dryer near water and never place a hair dryer in water.

        Sunday, April 06, 2008

        Three Phase Solid State Relay

        This is R-Y-B three phase 40A 440V AC Solid State Relay with 3-30 V DC Control Signal. It has Built in HeatSink and Fan. It is good for Controlling a Bank of heaters. This model could go upto 120A with SSR's in parallel for Proportional Control.

        Solid State Relays SSR.

        This is a Contacter replacement, it will switch R-Y-B phases. It is a high power SSR. In some places
        it is unwise to use an SSR, a Electromechanical Contacter will perform better. The merit of SSR is fast switching, no wear and tear. No dust humidity influence.

        Three Phase SSR

        Saturday, April 05, 2008

        Tacho Counter for Speed and Quantity Measurement

        This was a Custom Built Product for Converting a 10-100 V Signal from a Motor Tacho to pulses, to indicate the distance moved by Conveyor belt with Job Material. The Digital Indicator would indicate the speed and the Mechanical Counter would Log Quantity of Materials Moved.

        Process Control Instrumentation

        Tacho Counter

        Analog Blind Dial On Delay Timer

        It is called analog dial timer as it has no digital display, but the chip is digital it is CD4541. It is Mains operated, you could make on-delay or off-delay. By changing the caps and resistors or with even dip-switches you could get timing of few seconds to many hours. Circuit is Analog Timer 4541 .

        Analog Blind Dial On Delay Timer

        Some timers energize the relay after a set delay on power start. Some start with relay energized and turn off after set time. Motors and big systems cannot take fast turn-on and turn-off, Some systems will require sections or modules to start one after another as they are interdependent. So Timers in automation were made to effect such delays, the early ones were mechanical clockwork.

        Analog Timer

        The CD4541BC Programmable Timer is designed with a 16-stage binary counter, an integrated oscillator for use with an external capacitor and two resistors, output control logic, and a special power-on reset circuit. The special features of the power-on reset circuit are first, no additional static power consumption and second, the part functions across the full voltage range (3V¨C15V) whether power-on reset is enabled or disabled.
        • Available division ratios 28, 210, 213, or 216.
        • Increments on positive edge clock transitions.
        • Built-in low power RC oscillator.
        • Oscillator frequency range . DC to 100 kHz.
        • Power on Auto reset initializes all counters.


        Basic Electronics
        Basics of Electronics
        Product Production
        Work Discipline
        Testing Points
        Learning Electronics
        Electronics Theory

        Production Notes
        Prototype Fabrication
        Electrical Circuits

        Scots Guide Electronics
        Engineering - Wikibooks
        Design Lab - Jim Svoboda
        DC Circuits UOG
        Socratic Electronics
        Blobz Guide Electric Circuits

        Product Design
        Product Development
        Constant Current Source
        Good Voltage Regulators
        Insulation Resistance
        Digital Insulation Tester
        DN Schematic PCB 04
        DN Product Design 07

        Hobby Circuits
        VU Meter Circuits
        LED brightness control
        555 Incredible Chip
        Process Control
        liquid level measurement
        Thermocouples and RTD
        Design ADC Interface uC
        Thermocouple Amplifier
        IA Instrumentation 02
        Temperature on DMM
        Optical Proximity Switch
        Analog Mux - Data Acquisition

        Test Measurement
        Instrumentation Automation
        NI Test and Measurement
        DMM Digital Multi Meter
        Oscilloscope in T&M
        IA Automation 01
        Build Instruments
        Tektronix T&M Equipment
        Educators Corner – Agilent

        Power Electronics
        UPS Background
        Transformer Connections
        DN Power Electronics 03
        DN Power Electronics 02
        Half Bridge Convertor SG3525

        Interfacing Microcontrollers
        Embedded Process Control
        80C31 8052 Microcontroller
        Microprocessors and uC
        Embedded Systems Design

        Good Voltage Regulators
        Relays and Contactors
        Potentiometers Trimpots
        Prototype Boards Types
        Types of Capacitors
        Types of Switches
        Resistors How they Work
        Coils Transformers SMPS
        Mains Transformers Types
        DN Components Selection 05

        Tutor Gadgets
        Count-Up Timer
        Digital Logic Gates
        Electronics Tutors

        Teaching Instruments
        Charles Proteus Steinmetz
        Muntzing a Circuit Design
        Teralab Electronics projects
        Historical Instruments

        Tables, Charts, Videos
        Binary and Hex
        Resistor Color Code
        Ohms Law
        Giga, Tera, Pico, Nano
        High Resistance Materials

        School - Analog Design
        DN Analog Basics 06
        DN Op-Amps 01
        TI Semiconductors