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[KB6NU] 2018 No Nonsense Tech Study Guide - Electronic components and circuit diagrams
KB6NU's Ham Radio Blog /////////////////////////////////////////// 2018 No Nonsense Tech Study Guide - Electronic components and circuit diagrams Posted: 17 Apr 2018 11:30 AM PDT http://feedproxy.google.com/~r/kb6nu...m_medium=email I know that I posted this chapter earlier, but after recording this chapter for the audiobook version, I decided to make a few changes. I think the changes make it better..Dan Resistors, capacitors and capacitance, inductors and inductance, batteries Resistors are components that, as the name implies, oppose the flow of current. We use them to control how much current flows in a circuit. The higher the resistance, the lower the current. Most resistors have a fixed value, specified in ohms, but some are designed to be variable. That is, you can change the resistance of the resistor by turning a shaft or sliding a control back and forth. Variable resistors, also called potentiometers, are often used to allow users to adjust the way a device operates. QUESTION: What electrical component opposes the flow of current in a DC circuit? (T6A01) ANSWER: Resistor QUESTION: What type of component is often used as an adjustable volume control? (T6A02) ANSWER: Potentiometer QUESTION: What electrical parameter is controlled by a potentiometer? (T6A03) ANSWER: Resistance Another common electrical component is the capacitor. The most basic type of capacitor consists of two metal plates separated by an insulator, called a dielectric. When you put a DC voltage across a capacitor, an electric current flows into the capacitor until the voltage across the capacitor equals the DC voltage. This puts a positive charge on one plate and a negative charge on the other, thereby creating an electric field between the two plates. QUESTION: What type of electrical component consists of two or more conductive surfaces separated by an insulator? (T6A05) ANSWER: Capacitor QUESTION: What electrical component stores energy in an electric field? (T6A04) ANSWER: Capacitor QUESTION: What is the ability to store energy in an electric field called? (T5C01) ANSWER: Capacitance QUESTION: What is the basic unit of capacitance? (T5C02) ANSWER: The farad The third most common type of electrical component in amateur radio equipment is the inductor. Inductors are usually small coils of wire, and when a current flows through that coil of wire, a magnetic field is set up around the coil. QUESTION: What electrical component usually is constructed as a coil of wire? (T6A07) ANSWER: Inductor QUESTION: What type of electrical component stores energy in a magnetic field? (T6A06) ANSWER: Inductor QUESTION: What is the ability to store energy in a magnetic field called? (T5C03) ANSWER: Inductance QUESTION: What is the basic unit of inductance? (T5C04) ANSWER: The henry As amateur radio operators, we often use batteries to power our radio equipment. Some types of batteries are rechargeable, while others are not. QUESTION: Which of the following battery types is not rechargeable? (T6A11) ANSWER: Carbon-zinc QUESTION: Which of the following battery types is rechargeable? (T6A10) ANSWER: All of these choices are correct Nickel-metal hydride Lithium-ion Lead-acid gel-cell There are a couple of random questions about other types of components. QUESTION: What electrical component is used to connect or disconnect electrical circuits? (T6A08) ANSWER: Switch QUESTION: What electrical component is used to protect other circuit components from current overloads? (T6A09) ANSWER: Fuse Semiconductors: basic principles and applications of solid state devices, diodes and transistors Diodes are the most basic semiconductor component. They have only two electrodes, called the anode and cathode, and conduct current only when it is forward biased. That is to say, diodes only conduct current when the voltage on the anode is positive with respect to the cathode. When the diode is reverse biased, i.e., when the voltage on the anode is negative with respect to the cathode, the diode will not conduct current. QUESTION: What electronic component allows current to flow in only one direction? (T6B02) ANSWER: Diode QUESTION: What are the names of the two electrodes of a diode? (T6B09) ANSWER: Anode and cathode QUESTION: How is the cathode lead of a semiconductor diode often marked on the package? (T6B06) ANSWER: With a stripe Light-emitting diodes, or LEDs, are a particular type of diode. When current flows through them, they emit visible light, making them useful as indicators and as part of digital readouts. QUESTION: What does the abbreviation LED stand for? (T6B07) ANSWER: Light Emitting Diode QUESTION: Which of the following is commonly used as a visual indicator? (T6D07) ANSWER: LED Transistors are semiconductor components designed to control the current flow through them. They have three leads and one of those leads is used as the control pin. A current, in the case of the bipolar junction transistor, or a voltage, in the case of the field effect transistor, on the control pin controls the current flow between the two other pins. In some circuits, the transistor is used as a switch, and the control signal simply switches the current on and off. In other circuits, the transistor is used as an amplifier. When used as an amplifier, the current through the transistor is proportional to the input current or voltage. The ratio of output current to input current is called the gain of the transistor. QUESTION: What class of electronic components uses a voltage or current signal to control current flow? (T6B01) ANSWER: Transistors QUESTION: Which of these components can be used as an electronic switch or amplifier? (T6B03) ANSWER: Transistor QUESTION: Which of the following electronic components can amplify signals? (T6B05) ANSWER: Transistor QUESTION: What is the term that describes a device’s ability to amplify a signal? (T6B11) ANSWER: Gain QUESTION: Which of the following could be the primary gain-producing component in an RF power amplifier? (T6B10) ANSWER: Transistor Bipolar junction transistors are made up of layers of semiconductor materials that are either P-type, which means that it has a positive net charge, or N-type, which means it has a net negative charge. Each layer has an electrode, making the transistor a device with three leads. There are two types of bipolar junction transistors: PNP or NPN. A PNP transistor has two P layers, with an N layer sandwiched between them. An NPN transistor has two N layers, with a P layer sandwiched between them. QUESTION: Which of the following components can consist of three layers of semiconductor material? (T6B04) ANSWER: Transistor Another type of transistor often found in amateur radio equipment is the field-effect transistor, or FET. To control the flow of current through the field effect transistor, you use a voltage signal on the control pin. This voltage sets up an electric field inside the transistor, hence the name field effect transistor. FETs, like NPN and PNP transistors have three leads. QUESTION: What does the abbreviation FET stand for? (T6B08) ANSWER: Field Effect Transistor Circuit diagrams, schematic symbols, component functions When describing circuits on paper, we draw diagrams called schematic diagrams that show the components used in a circuit and how those components are connected together. Using schematic diagrams lets us describe how a circuit works and lets us reproduce a circuit more easily. The circuit components are represented by symbols that readily identify the type of component and its value or part number. QUESTION: What is the name of an electrical wiring diagram that uses standard component symbols? (T6C01) ANSWER: Schematic QUESTION: What do the symbols on an electrical schematic represent? (T6C12) ANSWER: Electrical components QUESTION: Which of the following is accurately represented in electrical schematics? (T6C13) ANSWER: The way components are interconnected Figure T-1 is a schematic diagram of a simple transistor circuit. In this circuit, the transistor is used as a switch that turns on a lamp when a positive voltage is applied to the input. QUESTION: What is component 1 in figure T1? (T6C02) ANSWER: Resistor Its function is to limit the input current. QUESTION: What is component 2 in figure T1? (T6C03) ANSWER: Transistor QUESTION: What is the function of component 2 in Figure T1? (T6D10) ANSWER: Control the flow of current QUESTION: What is component 3 in figure T1? (T6C04) ANSWER: Lamp QUESTION: What is component 4 in figure T1? (T6C05) ANSWER: Battery This battery supplies the current that lights the lamp. The circuit shown in Figure T2 is a simple power supply. Component 2 is a fuse. QUESTION: What type of switch is represented by component 3 in figure T2? (T6D03) ANSWER: Single-pole single-throw It turns the power supply on and off. QUESTION: What is component 4 in figure T2? (T6C09) ANSWER: Transformer QUESTION: What component is commonly used to change 120V AC house current to a lower AC voltage for other uses? (T6D06) ANSWER: Transformer Component 5 in Figure T2 is a rectifier diode. Rectifier diodes are designed to handle the higher currents found in power supply circuits. QUESTION: Which of the following devices or circuits changes an alternating current into a varying direct current signal? (T6D01) ANSWER: Rectifier QUESTION: What is component 6 in figure T2? (T6C06) ANSWER: Capacitor Sometimes, this is called a filter capacitor, and its function is to filter out remnants of the 60 Hz AC that are part of the varying direct current signal. QUESTION: What is component 8 in figure T2? (T6C07) ANSWER: Light emitting diode The LED is a pilot light, serving to alert a user when the power supply is on. QUESTION: What is component 9 in figure T2? (T6C08) ANSWER: Variable resistor Its purpose is to limit the output current of the supply. The circuit shown in Figure T3 is the output circuit of a transmitter. QUESTION: What is component 3 in figure T3? (T6C10) ANSWER: Variable inductor There are two variable capacitors in this circuit—component 2 and the unlabeled component. QUESTION: Which of the following is combined with an inductor to make a tuned circuit? (T6D08) ANSWER: Capacitor QUESTION: Which of the following is a resonant or tuned circuit? (T6D11) ANSWER: An inductor and a capacitor connected in series or parallel to form a filter When a capacitor and inductor are connected in series, the circuit has a very low impedance at the resonant frequency. When the capacitor and inductor are connected in parallel, the circuit has a very high impedance at the resonant frequency. QUESTION: What is component 4 in figure T3? (T6C11) ANSWER: Antenna Other components There are many different types of components in modern radio equipment. Below, we will describe the types of components you will need to know about to pass the Technician Class license examination. One of these is a relay. QUESTION: What is a relay? (T6D02) ANSWER: An electrically-controlled switch Meters are devices used to indicate many different values. Meters can indicate the output voltage of a power supply, the output power of a transmitter, and many other values. QUESTION: Which of the following displays an electrical quantity as a numeric value? (T6D04) ANSWER: Meter To make electronic circuits smaller, component manufacturers make devices that have many electronic components on a single piece of silicon. We call these integrated circuits. Integrated circuits, such as microprocessors, may have million of transistors inside them. QUESTION: What is the name of a device that combines several semiconductors and other components into one package? (T6D09) ANSWER: Integrated circuit Integrated circuits may perform either analog or digital functions. One type of analog integrated circuit that is very common is the voltage regulator. QUESTION: What type of circuit controls the amount of voltage from a power supply? (T6D05) ANSWER: Regulator When connecting electronic assemblies together, we often use cables with one or more conductors. Some of those conductors may have a shield around them that is connected to ground. QUESTION: Which of the following is a common reason to use shielded wire? (T6D12) ANSWER: To prevent coupling of unwanted signals to or from the wire The post 2018 No Nonsense Tech Study Guide Electronic components and circuit diagrams appeared first on KB6NUs Ham Radio Blog. |
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I will admit that it helped me years ago to only learn the right answer and not see all the possible answers at one time. But this test has been dumbed down to the point of where it makes no sense to even give it.
The FCC ought to just charge the person $100 every 10 yrs and just let anyone that wants a license have one, since it has turned into a over glorified cb radio anyways. I try to avoid 10m SSB, 6m SSB, and the FM frequencies as much as possible, just so I don't get into it with those LIDS. I like operating 6m when there is a band opening or for a contest, but the rest of the time there is no intelligence there. Just the fact that someone would use slow digital modes - just for the sake of using them, when I am trying to operate phone - and can hear stations 1000 miles away, tells me that they aren't willing to learn anything. When you try to teach them how to do something or how to act, it turns into a shouting match, where the one that shouts the loudest or the one with the most friends on the air, must always be right, because their other lid friends affirms that what their friend is doing is right - because we've always done it this way! Working digital modes over a fm repeater was one that really got to me the most. Like they believe that in a disaster that the repeater is always going to be there for them to use their walkie talkies on...
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[KB6NU] 2018 No Nonsense Tech Study Guide - Electronic componentsand circuit diagrams
On 18/04/2018 23:11, Channel Jumper wrote:
The FCC ought to just charge the person $100 every 10 yrs and just let anyone that wants a license have one, since it has turned into a over glorified cb radio anyways. Regrettably agreed, the RSCB (as it is now known) is responsible for the devastation of amateur radio in their efforts to keep the coffers filled. |
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