This video is about electrical wires. It describes common types, configurations of wire, and wire terminology. It explain the gauge system of rating wire size (diameter), circular mils, current capacity, and others.
This video describes Resistor Color Codes and how to read them. It relates Resistor Color Codes to scientific numbers and engineering notation.
This video continues part 1 by showing how a breadboard, also called a protoboard, is used to build electronic circuits without soldering, by guiding the student through 10 steps to build a blinking LED circuit based on the 555 IC timer chip. The circuit also needs 3 resistors, 1k, 4.7k, and 10k. It also requires a 10 uF electrolytic capacitor, an LED, some jumper wires, and a 6-volt battery or power supply.
Uses of Breadboard
A breadboard is used to make up temporary circuits for testing or to try out an idea. No soldering is required so it is easy to change connections and replace components. Parts will not be damaged so they will be available to re-use afterwards.
Almost all the Electronics Club projects started life on a breadboard to check that the circuit worked as intended.
The photograph shows a typical small breadboard which is suitable for beginners building simple circuits with one or two ICs (chips). Larger sizes are available and you may wish to buy one of these to start with.
This video introduces the breadboard, also called a protoboard, used to build electronic circuits without soldering. The first part of this presentation describes the features of a breadboard.
A breadboard (protoboard) is a construction base for a one-of-a-kind electronic circuit, a prototype. In modern times the term is commonly used to refer to a particular type of breadboard, the solderless breadboard (plugboard).
Because the solderless breadboard does not require soldering, it is reusable. This makes it easy to use for creating temporary prototypes and experimenting with circuit design. Older breadboard types did not have this property. A stripboard (veroboard) and similar prototyping printed circuit boards, which are used to build permanent soldered prototypes or one-offs, cannot easily be reused. A variety of electronic systems may be prototyped by using breadboards, from small analog and digital circuits to complete central processing units (CPUs).
I got hold of some 2600F capacitors that can dump hundreds of amps. Normally these are used in electric cars to handle sudden stops and starts. Instead, I use them to vaporize bits of metal, and show you the 3 most important capacitor equations along the way.
An electric double-layer capacitor (EDLC), also known as supercapacitor, supercondenser, pseudocapacitor, electrochemical double layer capacitor, or ultracapacitor, is an electrochemical capacitor with relatively high energy density. Compared to conventional electrolytic capacitors the energy density is typically on the order of hundreds of times greater . In comparison with conventional batteries or fuel cells, EDLCs also have a much higher power density.
A typical D-cell sized electrolytic capacitor displays capacitance in the range of tens of millifarads. The same size EDLC might reach several farads, an improvement of two orders of magnitude. EDLCs usually yield a lower working voltage; as of 2010 larger double-layer capacitors have capacities up to 5,000 farads. Also in 2010, the highest available EDLC energy density is 30 Wh/kg (0.1 MJ/kg) (although 85 Wh/kg has been achieved at room temperature in the lab), lower than rapid-charging lithium-titanate batteries.
EDLCs have a variety of commercial applications, notably in “energy smoothing” and momentary-load devices. They have applications as energy-storage devices used in vehicles, and for smaller applications like home solar energy systems where extremely fast charging is a valuable feature.
For more information about amplifiers, Google “inverting amplifier” “non-inverting amplifier” “instrumentation amplifier” “class A amplifier” “class B amplifier” “class AB amplifier” and that should give you a lot to chew on.
Afroman covers the basics of how transformers work, where to shop for step down mains transformers, and how to wire one up to mains voltages without killing yourself. European and North American wiring is discussed. He finishes up with a quick example of AC to DC conversion in an unregulated dual rail power supply.
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer’s coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer’s core and thus a varying magnetic field through the secondary winding. This varying magnetic field induces a varying electromotive force (EMF), or “voltage”, in the secondary winding. This effect is called mutual induction.
A tutorial on the LM317 voltage regulator. Shows you how to make a 1.25 to 25V adjustable voltage supply, or choose any other output voltage you want. An example of a fan speed controller is shown.
The LM117 series of adjustable 3-terminal positive voltage regulators is capable of supplying in excess of 1.5A over a 1.2V to 37V output range. They are exceptionally easy to use and require only two external resistors to set the output voltage. Further, both line and load regulation are better than standard fixed regulators. Also, the LM117 is packaged in standard transistor packages which are easily mounted and handled.
In addition to higher performance than fixed regulators, the LM117 series offers full overload protection available only in IC’s. Included on the chip are current limit, thermal overload protection and safe area protection. All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected.
Normally, no capacitors are needed unless the device is situated more than 6 inches from the input filter capacitors in which case an input bypass is needed. An optional output capacitor can be added to improve transient response. The adjustment terminal can be bypassed to achieve very high ripple rejection ratios which are difficult to achieve with standard 3-terminal regulators.
- LM317 datasheet from National Semiconductor (pdf)
- LM317 datasheet from Fairchild Semiconductor (pdf)
- LM317 datasheet from ON Semiconductor (pdf)
- LM317 datasheet from STMicroelectronics (pdf)
- LM317 datasheet from Texas Instruments (pdf)