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What is the purpose of a sine wave oscillator? - ✔✔Convert DC Energy to sinusoidal AC Energy. What is the purpose of a Hartley Oscillator? - ✔✔Convert DC Energy to sinusoidal AC Energy. What is the purpose of a colpitts oscillator? - ✔✔Convert DC Energy to sinusoidal AC Energy. What is the purpose of a RC phase shift oscillator? - ✔✔Convert DC Energy to sinusoidal AC Energy. What is the purpose of a crystal oscillator? - ✔✔Convert DC Energy to sinusoidal AC energy. What is the purpose of a sawtooth generator? - ✔✔Convert square wave energy to a sawtooth waveform. The FET is a ___________. - ✔✔Unipolar Device The element that current carries enter the FET through is called? - ✔✔Source The element that current carriers leave through is called? - ✔✔Drain
The flow of current carriers through the FET is controlled by this element. - ✔✔Gate What is the most common fault in a FET amplifier? - ✔✔A failed semiconductor component. What is it called when current flow remains constant? - ✔✔Saturation What are the 4 steps to troubleshoot an amplifier? - ✔✔(1.) Determine amplifier operation (2.) Determine if Vcc is present (3.) Determine if FET is good (4.) Isolate problem to bias circuit How is a Hartley Oscillator identified? - ✔✔They have two inductors in the feedback circuit. How is frequency determined in a Hartley Oscillators? - ✔✔The values of the components in the feedback circuit determine the frequency. How is a colpitts oscillator identified? - ✔✔Two capacitors in the feedback circuit. How is frequency determined in a colpitts oscillator? - ✔✔Frequency is determined by the components in the feedback circuit.
- Bistable Multivibrator Helps to convert DC energy to square wave energy - ✔✔Astable Multivibrator Converts DC energy to square wave energy - ✔✔Monostable Multivibrator Converts DC energy to square waves - ✔✔Bistable Multivibrator What type of blocking oscillator is a monostable Multivibrator? - ✔✔Trigger How is the output frequency determined in a bistable Multivibrator? - ✔✔The output frequency is one half the input trigger frequency. What is the purpose of a Schmitt trigger? - ✔✔To convert any input waveform of any shape and amplitude into square wave pulses of constant amplitude. In a Schmitt Trigger when is output high; when is output low? - ✔✔The output is high anytime the input exceeds the threshold. The output is low anytime the input signal is below the threshold. All FET biasing techniques accomplish two things: - ✔✔(1.) Place a positive voltage on the drain to establish current flow.
(2.) Reverse bias the source to gate PN junction to control current flow. The action of converting detected intelligence into sound waves that a human can hear. - ✔✔Reproduction The action of separating the low frequency intelligence from the high frequency carrier. - ✔✔Detection The ability of the receiver to isolate one station's frequency from the many frequencies present at the antenna. - ✔✔Selection Occurs when a transmitted electromagnetic wave passes through the receiver's antenna. - ✔✔Reception What are AM receivers? What does the AM broadcast band cover? - ✔✔AM receivers are electronic devices that pick up signals sent from AM transmitters. Frequencies go from 535 KHz to 1605 KHz Which is the most widely used FET? - ✔✔Common Source What is Calculated Av? - ✔✔Gm*Rd
RF- Given number LO-RF- is also referred to as the intermediate frequency (IF). The transistors in a Multivibrator are biased so.... - ✔✔That they are either in cutoff or saturation. When a transistor in a Multivibrator is ON, it's output voltage is ________. - ✔✔LOW In a Multivibrator, what is meant by a transistor being on? - ✔✔The transistor is in saturation. Free running Multivibrators generate a square wave output.... - ✔✔Anytime the operating voltage is applied. In an astable Multivibrator, what determines which transistor turns ON when power is first applied? - ✔✔The transistor that conducts first. What type of operation does a monostable Multivibrator use? - ✔✔Triggered What is the frequency of any monostable Multivibrator? - ✔✔The same as the input The frequency of an monostable Multivibrator is determined by____________. - ✔✔The input trigger frequency
Most faults in Multivibrators result in.... - ✔✔Either no output or a Vcc level on the output A Schmitt trigger produces a high output only when __________. - ✔✔The upper threshold level is exceeded. Schmitt triggers are also called ___________. - ✔✔Squaring amplifiers The purpose of a Schmitt trigger is to _____________. - ✔✔Convert any input to constant amplitude pulses. Schmitt triggers produce an output pulse anytime ....... - ✔✔The input exceeds the input threshold level. The purpose of Amplitude Modulation is to ____________. - ✔✔Transmit intelligence over long distances. The frequency range of AM receivers is ____________. - ✔✔535 KHz to 1605 KHz. The purpose of AM receivers is to ___________. - ✔✔Receive radio waves. If a signal measurement is incorrect between functional blocks, the fault is in _____________. - ✔✔The preceding functional blocks.
Decreasing Reverse Bias of VGS... - ✔✔Increases Id Positive Bias Voltage (VDD) is applied to the... N Channel FET - ✔✔The Drain Positive Bias Voltage on the Drain produces... N Channel FET - ✔✔Current flow _____ Bias Voltage (VGG) is applied to the _____. - ✔✔Negative/Gate A Negative Bias Voltage (VGG) on the Gate creates a____ in the FET. - ✔✔Barrier An Increase Negative Gate Voltage (VGG) causes... - ✔✔An increase in PN Junction Barrier. An increase in PN Channel Barrier causes... - ✔✔A decrease in Source-To-Drain Current. JFET Cutoff happens when... - ✔✔Negative Gate Voltage (VGG) increases to the point of no electron flow.
N Channel is made up of... - ✔✔A bar of N type Material with two island P Type Material. A P Channel FET is made up of... - ✔✔A bar of P Type of Material with two island N Type Material. selects and amplifies one frequency from the many picked up by the antenna. - ✔✔RF Amplifier Local Oscillator - ✔✔produces a frequency 455 KHz above the selected RF Mixer - ✔✔produces four frequencies
