Update for 16-03-22 16:15

tech/Mixer.wiki

@@ -0,0 +1,8 @@
+= Mixer =
+
+A mixer combines two input frequencies, and outputs both their sum and
+difference. This is also known as _hetrodyning_.
+
+Due to this property, a mixer can convert any signal to any other frequency.
+This is because the mixer operates regardless of relation between the input
+frequencies.

tech/Modulator.wiki

@@ -0,0 +1,4 @@
+= Modulator =
+
+A modulator is a circuit which takes some input carrier frequency and modulates
+it by some input, producing an output frequency.

tech/Multiplier.wiki

@@ -0,0 +1,4 @@
+= Multiplier =
+
+A circuit that creates a harmony of an input signal is a Multiplier. This is
+the same as multipling by some _n_ such that n is a natural number.

tech/Oscillator.wiki

@@ -5,4 +5,41 @@ the base signals upon which modulation can be performed to encode information.
 An Oscillator is also known as a Clock.
 
 Often osciallators are created using an amplifier and a feeback circuit to
-route some of the amplifiers output signal back into its input.
+route some of the amplifiers output signal back into its input. To make this
+oscialator produce a single frequency output, the feedback circuit must include
+a filter so feedback is present only in the intended frequency.
+
+Any oscillator's frequency can be variable or fixed.
+
+== Fixed frequency ==
+
+=== RC ===
+
+An RC oscialltor's feedback circuit is made up of Resistors (R) and Capactiors
+(C). Because of the combination of reacrance and resistance, the RC circuit
+shifts the phase of the feedback circuit so that the resulting signal, when
+amplified, reinforces the original signal
+
+=== LC ===
+
+An LC oscialltor is made up of an inductor(L) and Capacitor(C) connected in
+parallel or series to create a resonant circuit. This is sometimes called a
+tank circuit, as it stores electrical engergy, similar to a flywheel with
+mechanical energy. LC oscialltors are more stable than RC and can be used with
+a wider range of frequencies.
+
+=== Crystal ===
+
+A quartz crystal with a voltage applied creates a steady frequency that can be
+used as an osciallator, this is fare more accurate than an LC circuit.
+
+== Variable ==
+
+A Variable Frequency Osciallator (VFO) whose frequency can be adjusted, is
+used in adjustable tuners for radios. The frequency is alterted by changing the
+value of one or more components in a feedback circuit. A VFO is often made by
+having a variable capactior in an LC circuit.
+
+Other Variable Oscillators include a Phase Locked Loop (PLL) oscillator and a
+Direct Digital Syntehsizer (DDS). The accuracy of a DDS is comparable to a
+crystal

tech/electronics.wiki

@@ -43,7 +43,11 @@ Also see
 
 * [[AC]]
 * [[PEP]]
+
 * [[Oscillator]]
+* [[Mixer]]
+* [[Multiplier]]
+* [[Modulator]]
 * [[ADC]]
 * [[DAC]]