Soldermans Basic Electronics

Teralab Electronics projects - Robert Hunt

2008-05-23T08:22:00.000+05:30

This site is an attempt to document some of the physics experiments and science projects which I have conducted in my laboratory at home. These experiments include high vacuum, electron optics and electrostatics. There is also a virtual museum of scientific instruments, antique lamps and antique valves.

My father was interested in T.E.Lawrence and used to visit Pat and Joyce Knowles who looked after Lawrence's cottage. Because they lived way out in the country side, they were not connected to the electricity supply. Pat generated electricity to charge a small room full of accumulators using solar panels and windmills. Pat encouraged my scientific interest by giving me old electronic equipment to play with.

- Robert Hunt

Projects

Design and Development Notes 2004-6

2008-05-03T09:47:00.000+05:30

Over rate components at least double, if you need a 1A-100V-100uS diode, use a 2A-200V-50uS diode.
Unused CMOS inputs should have a pull up or pull down resistor, it should not float, or it oscillates.
Have a decoupling capacitor 104 that is 0.1uF or 100nF across the supply of every IC very near the IC supply pins.
A watchdog timer should be used in every microcomputer circuit like 8051 so that the system resets on hanging.
The reset on a microcomputer should be applied till the supply to it is stabilized, this will enable a clean start.
Use MFR (metal film resistor) 1% in all analog designs and if possible use only MFR for better reliability.
Electrolytic capacitors have a shelf life, if you need to store them you have to charge them every month.
If in your power supply you have a varistor, then you should have a fast acting fuse in series, as varistor fail as a short.
The current thru a 3mm or 5mm LED (light emitting diode) should not exceed 20mA, 15mA is quite good.
Analog ground (opamps), digital ground (CMOS) and power ground (relays and LED) should be separate, (linked at root)
Pull up or pull down resistors in TTL can be 10K and in CMOS 100K and in battery operated systems 1M.

Design and Development Notes 2004-5

2008-05-03T07:51:00.000+05:30

Keep functional blocks of circuits as modules or separate areas in a big PCB, this helps in testing and troubleshooting.
Power circuits, digital circuits and analog circuits should have separate supplies and ground when possible.
Inputs and Outputs are the points of electric abuse, opto isolate, use zener barriers with overrated devices.
When a microwave oven is turned on, a big spike is caused in the power line due to heavy inrush current on start up, Even pumps and motors cause such short time surges. This causes tripping of electrical protection circuits.
When a tree branch falls on the high voltage overhead electrical lines, they spark violently and supply trips.
Big or tall trucks go in small roads they may snap all low level cable or telephone wires on their way.
Do you need to turn on many equipments all at once? do it one after an other sequentially or use a timer for delays. This is because at peak power demand time, turning on all can cause your fuse to blow or worse.
When you design an equipment keep the controls minimum, too many options and too many knobs and dials are not good ergonomics. For your equipment to be user friendly use simple navigation and not menus nested 6 deep.
Wire and crimping of wires for supporting the high currents and high voltages must be carefully chosen. The copper cross section area gives its ability to carry current, the quality, thickness and flexibility of the insulation gives its voltage capability. The Tightness of the crimped contact will ensure long term reliability. Mechanical Stress prevention for all wiring is very important and guarded termination for user-operator safety.
BTA16600 and triacs of this series from ST have the metal TO220 tab electrically insulated from the device.
MOC3041 and others, switch triacs at zero crossover which reduces EMI-RFI and spikes. It means when the sine wave is close to zero volts the triac is turned on.
You have to ensure proper air circulation and fix proper heat-sinks with thermally conductive heat-sink compound or silicone grease with alumina. Anodized Aluminum heat-sinks with large surface areas and small fans are used in power electronic products for this purpose. If a component works very hot the specs will get derated, precision is lost and undesirable and unpredictable results will happen.

Design and Development Notes 2004-4

2008-05-02T13:45:00.000+05:30

In a circuit swap all PNP and NPN, reverse all diodes and el-caps, reverse the supplies and input polarities, most of the circuits may still work like they did before.
In a 3-1/2 digit meter circuit you may need 0.1% Resistors 10ppm or less, so in a 4-1/2 meter we need 0.01% Resistors 1ppm or less or temperature compensation circuits and trimpots.
A sharp bend in a PCB track is a huge inductance (say 1nH ) when it comes to RF. it may radiate or reflect, it may even act like an antenna and pick up RF from the SMPS, Motor or Cellphones nearby.
If one layer of PCB is a ground plane and second layer has wide tracks they may form a capacitance (say 1pF) with the PCB glass epoxy as dielectric, more so in multilayer PCB as dielectric is thinner.
If you need a 10.00K resistor 0.1% and you only have 1% in the market, you can trim lower values to higher values by removing the paint of the resistor and scratching the black metal film till you get the desired value.
7107 and 7135 of Intersil can be tested in-circuit, check Vref for 100mV or 1V reference, then short Vin and Vref the reading should be 1000 counts for 7107 and 10000 counts for 7135. ground plane should be good, no ground loops, PCB only glass epoxy and low leakage caps to be used, then reading will be stable, use some coating on soldered PCB.
An electrically Noisy environment can be simulated with a hair drier, or hot air blower. looping the NC (normally closed) contacts of a 230V Electrical Contacter-Relay can make it oscillate which makes a lot of electrical noise rich in EMI-RFI. This may be required for basic testing of timers, counters, uP, uC and embedded systems as they may malfunction in noisy environment.
Glass epoxy PCB have high insulation resistance, above 10 tera ohms, and are not hygroscopic which means they do not drink water vapor, this makes them very suitable for precision instrumentation and sensitive circuits.
Loose Contacts may have a resistance like 100mE (milliohm). A bit of corrosion and 10A of current will make that dissipate 100 * 10² = 10,000mW = 10W, if the contact area is 1 sqmm the heat will cause the resistance to increase, then the dissipation becomes more, sparking and welding may happen, it can even cause fire.
When using a sharp blade the cutting stroke must move away from you and make sure nobody is close, Wear protective or even plain glasses, If you use a blade with the stroke moving towards your body it will cut badly.
Power tools and machinery must be used only after exhaustive training and with safety precautions. The power tools used carelessly and wrongly can cause an injury which will last a lifetime or may even handicap you.

Design and Development Notes 2004-3

2008-05-02T13:09:00.000+05:30

CMOS gates and Opamps have a output drive capability of ~ 10-20mA, so when you drive a load say an LED use a series resistor to limit the current to 5mA to 10mA.
In a industrial environment many motors, DC drives and AC drives will be running, this will produce EMI, RFI, kickback spikes which cause microcontroller based equipment to hang. Use a watchdog timer for uC, opto couplers for all input and outputs, 4-20mA current signals for input and output, and a isolated wide range SMPS as power supply. more care is needed now as mobile phones and transmitters are filling the air with a lot of RF. so design circuits with care.
When you measure DC levels in 16bit accuracy or more you need resistors which have temp. coeff. of 10ppm, or you may have to put the entire circuit in a stable 45 deg oven. Thermoelectric effects, EMI, RFI, pA Leakage currents, ground loops, contact resistance all can make the readings drift and unusable.
When the number of digital chips you use in a project goes above 20 or 30 then it is better to use PLD or CPLD types from Altera, Xilinx or Lattice etc.. But when high speed is not required and for simplicity use microcontrollers.
A battery that can be charged is best charged in CC constant current and CV constant voltage modes, that means both current and voltage have to be limited. When a battery is deep discharged many times it will age fast, and an empty battery will take huge currents so limit current. overcharging a battery will kill it so after a voltage level is reached it should only trickle charge in mA and a battery has to be cut off on overload or before deep discharge
Look at this page on electromagnetic spectrum which will tell you about light and frequencies see at wikipedia.

Historical Electricity Teaching Instruments

2008-04-30T19:38:00.000+05:30

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.

LED brightness controler - Jaroslav Belza

2008-04-30T19:01:00.001+05:30

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.

Design and Development Notes 2004-2

2008-04-27T07:40:00.001+05:30

If the waveform on the scope droops then you may need to use a 10X attenuating probe or mode. this attenuator is at the tip of the probe hence better measurement possible, also very high frequency signals may be best transmitted over a 50 ohm impedance matched line to the scope.Never 'put or remove' ICs, cards or plug-in modules when the power to that system is on, power off system wait for some time for caps to discharge, then insert ICs or cards, applies to PCs too, USB and Firewire ports are exceptions as they are hotplug, anyway even in this, take a bit of care as some peripherals may cause some problems.
Karl Ferdinand Braun - In 1897 he built the first cathode-ray tube...oscilloscope. CRT technology is to this day used by most television sets and computer monitors. The CRT is still called the "Braun tube" (Braunsche Röhre) in German-speaking countries (and in Japan: Buraun-kan).
The inventor and developer of oscilloscope as a useful measuring instrument is Tektronix.
Have a lathe lamp or table lamp with a 40W edison-filament lamp (ordinary bulb) on your workbench.
Have an antistatic mat on the work or test table, if you cannot afford or get it then get a large aluminum sheet, laminate it with an insulating polycarbonate sheet and earth the metal plate with two 1M resistors in series.
Use thin multi strand teflon wires for your jumpers within a PCB, these are not damaged by your iron too.
Silicone shrink sleeves can withstand high temperature and use this in your work to make it safer and neat.
When you make a connection with a wire you need mechanical strain relief or on use connection will open.
Test a NPN transistor, DMM in 200K range. emmiter negative probe, collector positive probe, it should show open. while still holding that way press wet finger on base and collector, it may show some reading, then it is ok. for PNP swap probes polarity and do the same thing. the wet finger when pressed applies a base current in uA.
Testing a Mosfet - Transistor Tester - Testing Transistors - Basic Testing of Semiconductor Devices
Teflon tape can be used to make leak proof pneumatic or hydraulic connections if junctions are leaking.
Gold plating is used in connectors because it has low contact resistance and does not corrode or react
Persistence of vison around 16 frames a second (60mS) hence very fast events not seen, see in wikipedia.
Use a 100uF and 0.1uF CD in parallel to filter because the inductance of 100uF is a lot (the electrodes are wound as in a coil) and high frequency passes over and is filtered by the 0.1uF which has negligible inductance.
Try to use same family ICs in a circuit, like only LS or only HCT, if you mix up then you have to do a design review.

Design and Development Notes 2004-1

2008-04-26T13:03:00.001+05:30

High impedance points of circuit like 500 kilo ohm and above can pick up AC noise and DC leakage currents. this will affect the performance of circuit, so for DC you have to put a guard ring' of the signal ground around that point in PCB. For RF you have to shield with things related to iron and mu metal, for low signals even a copper shield will do.
Reinforce copper tracks on PCB with a copper wire when it needs to carry more current, tinning will improve a bit.
Small battery operated gadgets when turned on after a very long time may not work properly due to a thin oxide layer at the battery connector, replace cells if required, scratch and clean battery and connector surface, the reason is some gadgets consume so low power that the current cannot break a micronic oxide layer. Keep using regularly.
The Lead acid battery breathes a lot, so keep them in a well ventilated open space but rain proof. Use sealed maintenance free battery when possible, these are safe. they are costly and do not have a long life.
Percentage and ppm: when percentage becomes like 0.001% it is difficult to manage, so we use ppm-parts per million.5% means 5 parts in 100 parts. 23 ppm means 23 parts per million parts. 0.001% - shift the dp-decimal point four places to right it is 10ppm. 0.01% is 100ppm which is the variation of value of mfr resistors on temperature change.
Electronics assistant by simon carter on electronics2000 will help you learn some basics of electronic components, it is a windows-win32 application, it is a freeware.
emu8086 will help you learn the x86 opcode set, assembly language, mnemonics which is the foundation code on which even the pentium runs, first try the examples then tweak the examples and learn.

Manufacturing Engineering builds Design Notes

2008-04-26T11:02:00.001+05:30

Snubbers consisting of R-C should be used across switches, relay contacts, MOSFETS when switching inductive loads, this will absorb the spike and save the device.
Use RTV (room temperature vulcanizing) silicone rubber compound or Varnish on PCB-devices to avoid corrosion-dust. more so in industrial environment, ships and chemical industries.
Transformers used in SMPS could be split bobbin for product safety, and transformers should be resin impregnated, a human life cannot be lost by using a badly made product.
Ceramic capacitors leak a bit, electrolytics leak a lot but plastic or mica capacitors do not leak at all, near perfect. An oscillator with a RC time setting needs a plastic cap for stability.
12V lead acid batteries should be charged with a constant current CC and constant voltage charger the CV being 13.6V. Deep discharge and over charging will reduce the cycles.
Lead acid batteries need a monthly distilled water update to ensure long life, sealed lead acid dont need attention. Keep lead acid batteries in well ventilated area due to acid fumes.
In a SMPS which is not earthed the floating (unconnected) earth terminal will give a slight shock due to the two Y caps connected to earth from phase and neutral.
Electric Shock can kill hence take great care, Electrolytic capacitors burst and Transformers catch fire. turn off equipment after use. turn off all electricity when going out of town.
In industrial electronics equipment, connectors are a source of many problems, hence avoid connectors. vibrations, corrosion and frequent usage will result in strange problems.
A DMM in diode mode or resistance mode can be used to test IR diodes, take it under 100W lamp and measure, cover the IR diode and measure you will see a response in proper polarity.
Alumina-Aluminum oxide powder mixed in epoxy resin (araldite) can make thermally conductive insulating filler, heatsinks. The Alumina must be free of moisture and very dry.
Inductive kickback starts a tubelight or automobile as high voltages are produced when current in inductor is turned off. This also is the cause of failure in power semiconductors.

Learning Electronics by Experimenting

2008-04-26T05:01:00.001+05:30

How To Learn Electronics :

Theory must be studied once and referred again and again as you do practicals. One is by building DIY projects and then modifying them. Also Repair of equipment, troubleshooting, testing and calibrating. Then you know how components behave and real life limitations. Now design and engineer a product and test it at customer site. do a pilot production and test with more clients. Now you will learn to think based on practical application.

Do not mix mechanical and electrical connections, these leads to failures and frequent need of repairs and service.
80C51 ports can sink more current but source very less, hence use a 10k pull up at all the ports or outputs.
When using a double or multi layer pcb make one layer a ground plane, all decoupling caps ground linked to it.
RF or near RF multilayer PCB have 2 layers as ground plane and tracks in the layer in between, faraday cage.
High voltage or current stress, mechanical vibration, user misuse, High Energy stress (freq and voltage), aging (cycles) cause failure.
Before you open a PC remove power, telephone modem and LAN cables else finger and screwdriver in wrong place can zap chips.
The Contact resistance of connectors, thermocouple effects in connectors and solder joints and thermal gradients over the PCB can cause errors when you measure in high resolution.
When we draw circuits we have to keep in mind the readability, the circuit should be laid out according to the signal flow, the input output ports shown in the periphery of circuit.
Firmware must be developed in increments, tested in increments, backed up in increments, must be modular (include) reuse.
When you are soldering or cutting leads, room should have cross ventilation, protective glasses for eyes and a good stand.
Good earthing, servo motor regulated mains supply, earth leakage circuit breaker and over current circuit breaker, HRC fuse are some safety steps to take.
When working with HV or HE circuits wear shoes, keep yourself dry, the supply board should have above protections in red.
Small signal diode 1N4148 switches at 4nS, current of 70mA and 70V withstand capacity.
2N2222 and 2N2907 form a fast switching NPN-PNP pair and have been around for decades.

Basic Digital Electronics Tutors

2008-04-25T15:40:00.001+05:30

Astable 555 Timer Flasher

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If you are starting with electronics, this is the first step. So do it now ! Do-It-Yourself.

LED Running lights CD4017.
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Related Resources -

Digital up down BCD counter

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Realted Resources

The Source Code - digital-tutors - project page.

More Design Notes 2005

2008-04-25T14:39:00.000+05:30

The high voltage side must have layer to layer (mylar) insulation, means wind a layer and then put the yellow mylar tape, make tape concave so no strands should slip over to next layer, use split bobbin if possible. have terminations far away and enclosed for safety. vacuum impregnate with natural resin or epoxy depending on voltage and environment. product safety is very important.

In my circuits you might have seen i use HDSP-5501 common anode and HDSP-5503 common cathode available at digi-key, liteon LTS series like LTS543 may be same, at mouser i found out that MAN6980 of fairchild may also do.

Tristate output, High Impedance and Floating all mean the same when it comes to IC Inputs-Outputs. It means the pin is insulated from rest of circuit in the IC. That means it will not influence the node or bus it is connected to. A DMM terminals are floating means that the hand held plastic DMM has no electrical conductive link to earth or ground.

EMI-RFI causes-Switching Loads Simultaneously (inductive loads). Power factor correction capacitors and devices. Lightning strikes (enhanced by earth faults). Line Inductance (inductive kickback, resonance). DC and AC Drives for Motors. Rectifiers with large filters and stray inductance.

You can use hyper terminal to upload code to single board computers 80C51 like in BINARY or ASCII. Hyper Terminal Website. It is available in all windows default installations.

98spct38.pdf circuit in delabs analog circuits has some changes, use LF356 or TLO71 in place of CA3140 as it may be obsolete, the bias should be in pA, any FET input opamp is fine. The caps for sample hold are 10uF tantalum but for long hold times use 1uF plastic multilayer and clean-IPA + coat PCB with epoxy. 8 channel analog mux with sample hold, analog, pdf.

Design as per inventory : when you design a new product, we can design it with new types of parts, but it is also important to use parts that are standard to the company's inventory, Also you need to use up the parts which have been accumulated due to a discontinued product line or a failed idea. This way the design becomes more frugal and efficient. It also saves the company to build a new part type stock.

Muntzing a Circuit Design

2008-04-23T09:55:00.000+05:30

A History of TV is not Complete till you Learn about the Adventures of Earl Muntz. How he cut cost to Promote his TV Sets by Incremental Pruning of Parts from a Working unit.

What is important to learn from it though, is that we should not overdesign or underdesign. We need to design a cost effective product within customer budget. More Bells and Whistles in yet another Model. A Model to cater to every Purse. And a BareBones model for those who just can barely afford it.

History of Muntzing

Muntz Story

"He took a trip to New York City, checked into the Warwick Hotel and ordered three television sets delivered to his room: an RCA, a Philco and a Dumont. He turned all three televisions to the same channel and began pulling tubes from each one by one. When he pulled one tube too many from a set and the picture went black, he would make a note. Then, he put all the tubes back, changed the channel to another of the four television stations operating in New York City and repeated the test."

Engineering and Product Design Management

2008-04-23T07:55:00.000+05:30

ASICs are for only very big companies, or for products which have a long product life cycle. for a small company in consumer electronics it is not good, because by the time you get the ASIC out the product model is obsolete.
For low volume production use FPGA or CPLD, or even flash based microcontrollers, so that all your inventory can be reused and recycled, only change the software. but for say cell phones or a LAN card ASIC is fine. Volumes are good in cell phones and for lan cards the technology is matured.
Whatever the method keep design flexible and modular for reuse and to save cost. remember the hardware is difficult to alter, software can be altered even at customer site, flash has made this possible
In the future chips will be both analog and digital programmable with flash, and all the stores will have is blank chips. do not end up with too much inventory which is not good for the environment and is useful in only land fills.
Some FPGA, CPLD, ASIC links, WinCUPL, Design and Reuse, fpga4fun.
If a product gives three years life with minimum service support it can save itself from building a bad reputation. six years will establish the brand on a long term basis, twelve years of product life you will have the user of the product selling for you. if you want to improve sales by giving a new model every three years, you will need a lot of innovation on the product and you need to buy back the old ones for a big discount, you can bear some cost for brand loyalty and hence build a reputation for more sales in the future. This implies proper and sensible investments in product design and development, engineering, reliability, standards and quality will help a company survive long term.

If Inputs are Distorted, The Outputs are Noisy.
Even if the Amplifier is Very Good.

If Raw Materials are of Poor Quality, The Finished Goods are Defective.
Even if the Process and Machinery is State Of The Art.

If the Specifications are incomplete, The Prototype will be rejected.
Even if the Design and Tools are Perfect.

Solderman - 1707 AD

Enginnering and Servicing Notes

2008-04-23T03:56:00.000+05:30

This circuit of delabs has mistakes. 4A charger PWM, pdf in Power Electronic Circuits U2C must be a buffer not an inverter or swap pins 10 and 9 of U1C then only it will oscillate. Circuit File Name ST10_1.pdf .
This circuit of delabs has mistakes. Errata-2, +5/-5 dual supply from 12V DC, pdf Power Electronic Circuits 7905 regulator Input and Output lines to be swapped. use 79L05 for low current. Circuit File Name dact0017.pdf.
A Temperature Controller was fixed in a PCB manufacturer's Works, The readings was fluctuating and soon stopped working properly, the service engineer went and found that there was a strong smell of ammonia around the unit. When opened the tracks were eaten away by rapid corrosion and some of the component leads had disappeared. So another controller was made with extra coats of lacquer-varnish all over and RTV compound in many places. That solved the problem.
In above real life example, If production quantities were required then you need to vacuum impregnate modules in epoxy resin. These reworks or fixes will add rapidly to the BOM bill of Materials Cost. Then cost of fixing. So customers are of five types home-user, industrial, hazardous, military and medical. So Components are to be selected and product engineered and costed accordingly in that order.
If you put the DMM in 2V mode and measure the voltage across a ordinary LED near a 40W lamp you will see around 200mV. Turn off 40W lamp the mV will fall near 0. Even metal-can transistors with their top ground away will become photo sensors.
When you measure low voltages or high resistance like 1M with a DMM your body must not be in contact with the probe tips. Body resistance is low in comparison so error in reading or loading of mV from sensor, in sensitive and high impedance ranges.

Design Notes 2005

2008-04-22T13:42:00.000+05:30

Most pots have a dielectric insulation between metal pot shaft and terminals of 1KV or more. Some commercial pots may have lesser breakdown voltage and that will be a product safety issue. So either way use Plastic Knobs or pots with plastic shafts.
Design the product in such a way that neither the pot terminals or pot switch is used for mains voltage, instead use the pot switch or variable resistance for signaling and the mains can be switched with Relay or Thyristor.
Unused high impedance inputs of opamps or gates or any IC should be pulled-up or down.
High Impedance inputs which have to float can be made noise immune with a small cap to ground. Like a 102 CD.
Revise your electronics basics and theory at Doug Gingrich's PHYS395 Course.
If an opamp circuit with feedback oscillates, then a cap at the right place can stop it, it will dampen the oscillations, just like eddy current dampening in moving coil meters. One way is a cap across the feedback resistor another way a cap between inv- and non-inv+ inputs. A closed loop system may oscillate at border points. The value of cap depends on how fast (response time) the system has to be and the type of oscillations seen.
Hysteresis is like on at 300 off at 304 like in heaters or air conditioners. If you on-off at sharp 300 there is a chatter or oscillation. This is called dead-band in temperature control. In above example 304-300=4 is the dead-band.
Do not club Heatsinks unless the heatsink is very big or the clubbed components form a part of a current sharing set. If you club say two TO220 devices one dissipating 10W with a 2 Watt heating device, you may reduce reliability of the 2W device. Then clubbing parallel current sharing devices on one heatsink may be a good idea as it may reduce thermal runaway, also parallel power transistors should each have 0.1E in emitter path, this also can force load sharing on lazy devices.

Charles Proteus Steinmetz

2008-04-22T12:36:00.000+05:30

Charles Proteus Steinmetz

Charles Proteus Steinmetz (April 9, 1865 - October 26, 1923) was an American Mathematician and Electrical Engineer. He fostered the development of alternating current that made possible the expansion of the electric power industry in the United States, formulating mathematical theories for engineers. He made ground-breaking discoveries in the understanding of hysteresis that enabled engineers to better design electric motors for use in industry.

Charles Proteus Steinmetz electrical engineer

"Eickemeyer wanted to expand into electrical motors and generators, a brand new field in 1889."

The Reason i remembered it was...I was seeing Blogger Play, which is very addictive. I clicked a Photo, which lead me to a story of a Cat and Mouse. The mouse triggered my memory of the story behind hysteresis, which i had read years back, in a very old Readers Digest. It had something like this...."When GE Motors Manufacturing faced the Problem of the motors Heating up, they heard of Charles Proteus Steinmetz.......Find out the rest yourself. !

VU Meter Circuits and Projects

2008-04-22T08:55:00.000+05:30

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

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.

Oscilloscopes in Test Measurement

2008-04-21T08:47:00.001+05:30

The usefulness of an oscilloscope is not limited to the world of electronics. With the proper transducer, an oscilloscope can measure all kinds of phenomena.XYZs of Oscilloscopes - Tektronix

A Tektronix model 475A portable analogue oscilloscope, a very typical instrument of the late 1970s. This dual-trace, dual-sweep instrument had a horizontal bandwidth of 250 MHz, a maximum vertical sensitivity of 5 mV per division, and maximum (unmagnified) horizontal sweep speed of 10 ns per division. - Oscilloscope - Wikipedia

Read More about Oscilloscope

National Instruments - Test and Measurement

2008-04-19T09:58:00.001+05:30

National Instruments - Test and Measurement

For the past 30 years, National Instruments has been a technology pioneer and leader in virtual instrumentation - a revolutionary concept that has changed the way engineers and scientists in industry, government, and academia approach measurement and automation.

LabVIEW, Data Acquisition, Modular Instruments, PXI, Programmable Automation Controllers.

Here is a page from an old NI Catalog. RS-232 Tutorial of NI. drag-drop image to read.

Texas Instruments - TI Semiconductors

2008-04-19T09:21:00.001+05:30

Texas Instruments - TI Semiconductors

Texas Instruments, better known in the electronics industry (and popularly) as TI, is an American company based in Dallas, Texas, USA, renowned for developing and commercializing semiconductor and computer technology. Read More Texas Instruments - Wikipedia, the free encyclopedia.

Analog, DSP, Digital Signal Processing, Power Management, Data, A/D Converter, Analog to Digital, Converters, Microcontroller, Mixed Signal, RF IF, Amplifier, Linear, Logic, Integrated Circuit, IC's, Switches, Multiplexer, Thermal Management, - Texas Instruments Semiconductor Chip Chipset Manufacturing.

Applications Active Matrix

The Scots Guide to Electronics

2008-04-19T08:01:00.001+05:30

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 ...

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

Category Engineering - Wikibooks

2008-04-19T06:38:00.001+05:30

Category Engineering - Wikibooks

This category contains a number of subcategories, books, and pages related to engineering in general. Books can be found on the Engineering Bookshelf. 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.

and many more at Wikiversity

School of Analog Design

2008-04-18T20:38:00.001+05:30

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.