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+---
+id: jbf1
+title: Breadboards
+tags: [electronics]
+created: Sunday, June 23, 2024
+---
+
+# Breadboards
+
+## Contact pins
+
+- Beneath the plastic casing, the contact holes are connected to one another
+  making a continuous circuit connection
+
+## Terminal strips
+
+The holes in the middle portion. They are connected in groups of five and
+comprise two groups separated by the ditch. The terminal strips are not
+connected accross the ditch thus each of the two strips are electrically
+separate.
+
+## Related notes
diff --git a/zk/Circuits.md b/zk/Circuits.md
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----
-tags:
-  - electricity
-  - electronics
----
-
-# Circuits
-
-An electrical circuit is a set of electrical components connected in such a way
-that current flows in a loop from a voltage source, through the circuit elements
-and back to the voltage source.
-
-Below is a basic circuit representing a 9-volt
-[battery](Cells_and_batteries.md#cells-and-batteries)
-with a 10,000$\Omega$
-[resistor](Resistance.md) attached
-accross its terminals. Through the application of
-[Ohm's Law](Ohms_Law.md) we can
-determine that the maximum current will be 0.9 miliamps.
-
-![](/img/basic-circuit.png)
-
-## Open and short circuits
-
-A circuit with a break in its loop is called an **open circuit**. When a circuit
-is open, no current flows. We can induce an open circuit through the use of a
-switch component that closes and breaks the circuit when invoked.
-
-A **short circuit** is a path in a circuit that allows current to flow with
-little or no resistance. This is usually unintentional and results in excessive
-current flowing through the circuit. A short circuit is the opposite to an open
-circuit. With an open circuit there is an infinite resistance between the two
-terminals.
-
-## Vertical circuit diagrams
-
-Sometimes circuits can be represented in a vertical manner rather than in an
-actual circuit. This is done to simplify the representation. In this approach
-current is represented as flowing in a straight line from the voltage source
-(represented with a circle) to ground.
-
-The circuit below is functionally identical to the previous circuit but
-represented vertically:
-
-![](/img/vertical-circuit.png)
diff --git a/zk/Digital_circuits.md b/zk/Digital_circuits.md
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----
-tags:
-  - electronics
----
-
-# Digital circuits
-
-Ultimately every process in a computer is the product of a digital
-[circuit](Circuits.md) that is
-working on binary values. In contrast to electrical circuits, digital circuits
-are not represented in an
-[analogue](Analogue_and_digital.md) fashion.
-
-Analogue circuits work on the basis of real continuous phenomena in the world:
-charges and currents. As a result, the key properties of a circuit - voltage,
-current and resistance - can vary over a wide range of values. This is the
-reason that we require components like batteries and resistors: to control the
-natural flow of current and ensure that it only runs within desired parameters.
-
-In a standard electrical circuit, voltage, current and resistance can vary over
-a wide range of values however in the binary context we want to deal with
-discrete values (zeros and ones) which can be fed into the various
-[logic gates](Logic_gates.md).
-
-We therefore need a way to represent 'on' and 'off' as single quantities. We do
-this by stipulating that a given voltage corresponds to 'on' (high) and another
-corresponds to 'off' (low). Of course these are not really discrete values since
-voltage is inherently analogue but we basically binary-encode them. Formally
-'on' has a voltage of 1 and 'off' has a voltage of 0. In reality 'on' tends to
-be within 2-5V depending on the circuit design and anything between 0 - 0.8V is
-considered off.
-
-The [transistor](Transistors.md) is
-the electrical component that enables us to represent given voltage ranges as
-being 'on' or 'off'.