Category: Tutorial videos

It's not the volts it's the amps

“It’s not the volts that kill you, it’s the amps!”

Afroman debunks the popular myth that it’s not the volts that kill you, it’s the amps. Basically, the volts directly determine the current flowing through your body, so the phrase is stupid and dangerously misleading.

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4 wire measurement

4 wire (Kelvin) resistance measurement tutorial

Most multimeters will allow you to measure resistances in the 1 ohm to megahohm range with a high degree of accuracy. But they are very inaccurate at measuring resistances in the milliohm range. The multimeter’s cable and connector resistances may be more than the resistance you are trying to measure. This video will show you […]

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Amplitude modulation

Amplitude Modulation tutorial & AM radio transmitter circuit

This video covers the history of the discovery of radio waves, to the creation of simple oscillator based radio transmitters. Then I explain what modulation and amplitude modulation are, and show you how to build a low powered AM radio transmitter out of a TL072 dual op amp IC.

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Peak detector circuit tutorial

Peak detectors are used when you have a rapidly changing AC input signal, and you want to obtain the peak voltage the signal reaches. Peak detectors are really simple to make – just a diode and a capacitor in their simplest form. In the video I give an example where I use a peak detector […]

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comparator circuits

Op amp comparator tutorial and clapper circuit

Comparators are a very handy circuit block that everyone should know. The basic idea is that you have a reference voltage, and as your input goes above or below that voltage, the output of the comparator goes high or low. In the video I give an example clapper circuit that toggles an LED on and […]

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Inductive spiking

Inductive spiking tutorial

When switching inductive loads you have to put a diode in antiparallel with the load, else you risk blowing up your transistor due to inductive spiking. This video explains it all. Bonus: Here is an online circuit simulator that you can use to simulate inductive spiking behaviour.

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Passive RL low pass filter tutorial

This video shows how you can use RL filters to filter out high frequency signals. An example audio crossover circuit for a woofer speaker is given.

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inductance

Inductance basics

This video covers what inductance is, the units (henries), and how inductance increases when a core material is used.

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inductor

Inductor basics – What is an inductor?

This video covers the basics of inductors – how they work and what effects they have on electronic circuits. A quick low pass LC filter example is given.

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Circuit simulation in LTSpice tutorials

Circuit simulation can save you a lot of grief when designing advanced circuits. Instead of building something then wondering why it doesn’t work, a simulator can speed up the debugging process by letting you quickly change component values to see how the circuit responds. LTSpice IV is a freely available circuit simulation package from Linear […]

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Passive RC high pass filters

This video builds upon the basics I covered with my low pass filter tutorial, so make sure you have seen that video first. This video shows you how high pass filters affect sine waves and square waves of different frequencies, and compares the bode plots of high and low pass filters. By the end of […]

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What is a low pass filter? Passive RC low pass filter tutorial

This video covers the basics of low pass filters – how they affect signals, and how to design your own. By the end of the video you’ll know how to filter out high frequencies, which may prove useful when designing subwoofer crossovers etc. They are also handy for smoothing voltage ripple out too. You’ll also […]

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LM317

LM317 Adjustable Voltage Regulator Tutorial

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. This video builds on material covered in the fixed voltage regulator tutorial so you should check that out if […]

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voltage regulator

Voltage regulator tutorial and USB gadget charger circuit

This video covers the basics of linear voltage regulators – what they do, how to wire them up, and where to find them. Then I give a basic example of how to build a 5V supply that can be used to power USB powered gadgets. This video builds upon material covered in the transformer and […]

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diode

Diode tutorial and AC to DC conversion

This video covers the basics of diodes, bridge rectifiers, and how to build simple unregulated AC to DC power supplies than can handle a few mA up to several Amps. I recommend watching my transformer tutorial first if you are confused about where I am getting the AC voltages from. The voltage regulator tutorial is […]

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