Eagle Schematic Tutorial 

I wrote up a Eagle tutorial for another user on this forum, but I thought, what the heck someone else might find it useful ...

Ohm's Law for Beginners (or The Amp-Hour Fallacy) 

Just about once a day, somebody writes in with, “My boom box has a dead battery that says 12 volts, 1.8 amp-hours. The new battery says 12 volts, 2.4 amp-hours. Will the extra amp hours burn up my radio?”
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Capacitor ESR Meter 

What is ESR and How Can It be Tested?

As the allmighty Samuel M. Goldwasser says, "ESR (Equivalent ...

Cheap ARM Starting Kit 

I agree, that it's still complicated to get started with, but ARM7 until recently was the lowest chip core in the family ...

Method to Make Project Panels (Warning: Detailed Info!) 

When laser printers first came into coomon use (in the workplace anyway), here's a technique I came up with to make fairly ...

UNIT Committment solution using Dynamic programming 

INTRODUCTION

The unit commitment is an optimization problem that economically schedules generating units ...

LED Switching Regulator 

I was bored at work and had an idea so I started playing around in LTSpice and came up with this circuit to power a couple ...

Ohms Law 

Ohms Law

The relationship between current(I), voltage(V or E), and resistance(R) was discovered by a German scientist named Georg Ohm. This relationship is named Ohms Law in his honor. Ohm found that the current in a circuit varies directly with the voltage when the resistance ...

The Breadboard 

Introduction
When building a permanent circuit the components can be grown together (as in an integrated circuit), soldered together (as on a printed circuit board), or held together by screws and clamps (as in house wiring). In the laboratory, we want something that is easy to assemble and easy to change. We also want something that can use the same components that real circuits use. Most of these components have pieces of wire or metal tabs sticking out of them to form their terminals.

How it Works
The heart of the solder-less breadboard is a small metal clip that looks ...

The Oscilloscope 

The oscilloscope is basically a graph-displaying device - it draws a graph of an electrical signal. In most applications the graph shows how signals change over time: the vertical (Y) axis represents voltage and the horizontal (X) axis represents time. The intensity or brightness of the display is sometimes called the Z axis. (See Figure 1.) This simple graph can tell you many things about a signal. Here are a few:

• You can determine the time and voltage values of a signal.
• You can calculate the frequency of an oscillating signal.
• You can see the "moving parts" of a circuit represented by the signal.
• You can tell if a malfunctioning component is distorting the signal.
• You can find out how much of a signal is

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Determine Voltage Drop Across Resistors 

I learned this from http://www.bcae1.com/resistrs.htm
I know some true nooBs would like this info so i decided to ...

Digital Frequency Control 

RadioRon & I were discussing digital frequencies control solutions in another thread about radio transmission & ...

Resistor colour code and values chart 

Here's a resistor colour code chart I made awhile ago.

It isn't the most comprehensive chart, it omits things ...

Motor Sizing For Moving Robots 

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PLEASE REFER TO THE INCLUDED DIAGRAM
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Using Oscilloscopes 

Oscilloscope Application

OSCILLOSCOPE LEADS
Oscilloscope leads are available as simple screened cable with 'crocodile clip' terminations or as 'probes' switchable between 'Times One' (X1) and 'Times Ten' (X10), also fixed attenuating X10 probes may sometimes be seen. Other types are rare enough to ignore. When a probe is switched to X10 an internal attenuator reduces the signal seen by the 'scope to one tenth of that at the probe's tip - what you measure with the 'scope needs multiplying by ten to obtain the correct magnitude.
The reason for using a probe is this :-
An oscilloscope may have an input impedance of 1 Meg with 47pF in parallel; this may seem good enough but if you want to look at square waves or high frequencies this capacitance will act as a filter, rounding the corners of transients and reducing the apparent magnitude of high frequencies. If you start to probe around on high impedance circuits as are often used in CMOS logic then the 1 Meg resistance can start to affect the operation of the circuit you are trying to study.
A simple X10 probe could be just a 9 Meg resistor in series with the 'scope, this would work perfectly for DC but if a small adjustable capacitor is placed in parallel with this 9 Meg resistor it becomes possible to tune the circuit's AC response. An overall effective impedance of 10 Meg with a parallel capacitance of 5pF is easy to achieve. Setting this adjustable capacitor to match your 'scope is referred to as compensation and must be checked if a new probe/scope combination is used, every 'scope is different.

PROBE COMPENSATION
If accurate measurements are to be made, the effect of the probe being used must be properly adjusted to match the oscilloscope's input circuit using the internal calibration signal or some other square wave source.
1. Connect probe to INPUT jack. Connect ground clip of probe to oscilloscope ground terminal and touch tip of probe to CAL terminal (usually a small pad or pin in a corner of the front panel).
2. Select single trace operation on channel 1 then channel 2, perform steps 3 to 5 for each in turn.
3. Set the probe for 10:1 attenuation (X10 position) and VOLTS/DIV to 10mV/div.
4. Set oscilloscope controls to display 3 or 4 cycles of PROBE ADJ square wave at 5 or 6 divisions amplitude.
5. Adjust compensation trimmer on probe for optimum square wave shape (minimum overshoot, rounding off, and tilt).

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Magnets and Electromagnets 

Magnets and electromagnets have many uses, every electric motor, generator or transformer requires a magnetic field for it's operation. With the exception of a few special types, all use electromagnets. The magnets mounted on large cranes are used to lift heavy loads. Magnetism makes the generator supplying the electricity to your home work and the radio, telephone and most other electrical gadgets work.

The properties of Magnetism were known to the Greeks as early as 700 B.C. It was found that a certain type of ore had the power to attract pieces of iron which were in it's ...

Voltage 

The electric pressure that must be applied to cause electron movement is called voltage. When such a voltage is applied to a conducting medium, free electrons move progressively from atom to atom and constitute what is known as ...

Current and Conductivity 

A current flow path is provided by wires or other metals and thus form conductors of electricity. The ability of a substance to conduct electric current is termed conductivity. ...

Basic Soldering & Desoldering Guide 

The most fundamental skill in order to construct any electronic project is soldering (and desoldering). This article will explain how to do it.
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