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This notation is designed to be relatively easy to write. This is achieved by not drawing ultra complex ASCII art boxes of every component. It would be slightly more readable if we did that, but prioritizing the writer here.
Two wires are only joined if + is given. E.g. the following two wires are not joined:
  |
--|--
  |
but the following are:
  |
--+--
  |
Simple symmetric components:
  • -, + and |: wire
  • A: AC source. Parameters:
    • Hz: frequency
    • V: peak voltage
  • C: capacitor
  • D: DC source. If only one side is given, the other is assumed to be at a ground
  • G: ground. Often used together with D, e.g.:
    D_10---R_10---G
    means applying a voltage of 10 V across a 10 Ohm resistor, which would lead to a current of 1 A
  • L: inductor
  • R: resistor
  • V: Voltmeter without explicit positive and negative sides
  • X: Josephson junction
Asymmetric components have multiple letters indicating different ports. The capital letter indicates the device, and lower case letters the ports. The wires then go into the ports:
  • aDc: diode
    • a: anode (where electrons can come in from)
    • c: cathode
    Sample usage in a circuit:
    --aDc--
    Can also be used vertically:
    |
    a
    D
    c
    |
    We can also change the port order, the device is still the same due to capital D:
    --cDa--
    
     |
    Dac--
    
     |
    Dca--
    
       |
    --caD
  • sgTd: transistor
    • s: source
    • g: gate
    • d: gate
    Sample usage in a circuit:
    ---+
       |
    --sgTd--
    All the following are also equivalent:
       |
       g
    --sTd--
        |
    --Tsgd--
       |
  • pVn: Voltmeter with explicit positive and negative sides
  • dIs: electric current source. Electrons leave from s and go into d
Numbers characterizing components are put just next to each component with an underscore. When there is only one parameter, standard units are assumed, e.g.:
+-----+
|     |
C_1p  R_2k
|     |
+-----+
means:
  • a capacitor with 1 pico Faraday
  • a resistor with 2 k Ohms
Micro is denoted as u.
Wires can just freely come in and out of specs of a component, they are then just connected to the component, e.g.:
D_10---R_10---G
means applying a voltage of 10 V across a 10 Ohm resistor, which would lead to a current of 1 A
If a component has more than two parameters, units are used to distinguish them when possible, e.g.:
A_1kV_2MHz
means an AC source with:
Main implementations: the same as electronic switches: vacuum tubes in the past, and transistors in the second half of the 20th century.
Although transistors were revolutionary, it is fun to note that they were just "way cheaper and more reliable and smaller" versions of exactly the main functions that a vacuum tube could achieve
The first working one in 1947 by John Bardeen and walter Brattain in Bell Labs Murray Hill.
People had already patented a lot of stuff before without being able to make them work. Nonsense.
As the name suggests, this is not very sturdy, and was quickly replaced by bipolar junction transistor.
As of 2020, not used anymore in logic gates, but still used in amplifiers.
This is the cutest product name ever.
Since 1992, Mr. SQUID has been the standard educational demonstration system for undergraduate physics lab courses.
YBCO device, runs on liquid nitrogen.
This is how electronic circuits are normally prototyped!
Once you validate them like this, the next step is usually to move on to printed circuit boards for more reliable production setups.
Breadboards are a thing of beauty and wonder.
Figure 1. Point-to-point constructions on woden boards. Source. Predecessors to breadboards from where the name came. A thing of beauty, so vintage. You could actually write stuff on those with a pencil!
When Ciro Santilli was studying electronics at the University of São Paulo, the courses, which were heavily inspired from the USA 50's were obsessed by this one! Thinking about it, it is kind of a cool thing though.
Video 1. Tutorial on LC resonant circuits by w2aew (2012) Source.
Video 2. LC circuit dampened oscillations on an oscilloscope by Queuerious Guy (2014) Source. Finally a video that shows the oscillations without a driving AC source. The dude just move wires around on his breadboard manually, first charging the capacitor and then closing the LC circuit, and is able to see damped oscillations on the oscilloscope.
Video 3. Introduction to LC Oscillators by USAF (1974) Source.
Video 4. LC circuit by Eugene Khutoryansky (2016) Source. Exactly what you would expect from an Eugene Khutoryansky video. The key insight is that the inductor resists to changes in current. So when current is zero, it slows down the current. And when current is high, it tries to keep it going, which recharges the other side of the capacitor.
In the LC circuit:

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