# Maintenance Final

 AC Current DC Current Resistor Voltage = Resistance x Current Current = Voltage / Resistance Resistance = Voltage / Current Power = Voltage x Current 10^3 Kilo 10^6 Mega 10^-3 Milli 10^-6 Micro 10^-9 Nano Total Resistance of Series circuit = Sum of individual Resistances Current through a series circuit = Constant The sum of the individual voltage drops around a series circuit = The total applied voltage The total resistance of a parallel circuit = The reciprocals of the individual resistances. RT = 1/(1/R1+1/R2+1/R3) Voltage in a parallel circuit = Constant across each component of the circuit. Total current in a parellel circuit = The sum of the individual branch currents Impedance is the combined effect of: ResistanceCompacitive Reactance (Xc)Inductive Reactance (XL) Capacitive Reactance is measured in ohms and (increases, decreases) as frequency increases. Decreases Inductive Reactance is measured in ohms and (increases, decreases) as frequency increases. Increases Impedance specifications on loudspeakeres and audio inputs and outputs are specified at a frequency of... 1KHz Most devices utilize ____ voltage. DC Power supplies step down the incoming ____ voltage and convert it to ____ voltage. ACDC Power Supplies that are found in older equipment, are less efficient, easier to service, less complex, more expensive, and more reliable. Linear Power Supply Power supplies that are found in almost all new devices, are more efficient, more complex and difficult to repair, less expensive, smaller, and less reliable. Switching Power Supply Transformer A _______ steps down (or up) incoming ___ voltage to a little in excess. TransformerAC Rectifier Capacitor Provides means of adjusting the resistance within a circuit Potentiometers Opposes a change in current Inductor Gain = V out / V in Gain expressed in dB: dB gain = 20 Log (V out / V in) % Total Harmonic Distortion Square root of the sum of the squares of the individual harmonic distortion values. %THD = √[(%2nd)^2+(%3rd)^2...] When communicating either Sound Pressure Level or Voltage in dB, the following formula should be used: 20 Log (Voltage measured / Voltage reference) When communicating Power in dB, the following formula should be used: 10 Log (Power measured/ Power reference) Doubling of voltage = ___ dB Doubling of power = ___ dB 63 dBV reference = 1 V dBu reference = .775V dBm reference = 1 Milliwatt Of the semiconductor material types, the ___ type has a deficiency of electrons whereas the ___ type has an abundance of electrons PN Opposes current flow in one direction and allows it to flow readily in the opposite direction Diode Diode Transistor Identify this device and its elements: Vacuum Tube Triode The maximum current flow through the plate of a vacuum tube is called... Saturation The minimum current flow through the plate of a vacuum tube is called... Cutoff The fixed ___ voltage applied to the grid of a vacuum tube is referred to as... the bias voltage Class ___ means the tube or transistor is operating during the full 360 degree cycle of the input signal. A ______ are high gain voltage amplifiers with a differential input and usually a single-ended (unbalanced) output. Op amps Op amp Op amps require what kind of power supply? Bipolar The gain factor from op amps = Feedback resistor / input resistor Op amps have a very _____ input impedance and a very _____ output impedance. HighLow The rule of thumb for good voltage (signal) transfer is the ______ Z should be on the order of ___x the _______ Z Load10Source ________ pass high frequencies more readily than lower frequencies. Capacitors _______ pass lower frequencies more readily than higher frequencies. Inductors High pass filter Low pass filter Band stop filter Band pass filter Two signals of identical amplitude and phase applied to a differential (balanced) input Common Mode Two signals of opposite polarity applied to a differential input. Differential Mode An input having both a Hi(+) and Lo(-) signal input relative to ground that detects only the difference in voltage at the respective inputs. Differential Input Vacuum tube Vacuum tube Name the parts: Transitor AuthorSeanHatfield ID319703 Card SetMaintenance Final DescriptionMaintenance Final Updated2016-05-03T18:46:32Z Show Answers