1.04 UTF-8 J 0 0 1243588 E7A01 What is a bistable multivibrator circuit? 0 An "AND" gate 0 An "OR" gate 0 A flip-flop 1 A clock 0 E7A02 How many output level changes are obtained for every two trigger pulses applied to the input of a "T" flip-flop circuit? 0 None 0 One 0 Two 1 Four 0 E7A03 The frequency of an AC signal can be divided electronically by what type of digital circuit? 0 A free-running multivibrator 0 A bistable multivibrator 1 An OR gate 0 An astable multivibrator 0 E7A04 How many flip-flops are required to divide a signal frequency by 4? 0 1 0 2 1 4 0 8 0 E7A05 What is the characteristic function of an astable multivibrator? 0 It alternates between two stable states 0 It alternates between a stable state and an unstable state 0 It blocks either a 0 pulse or a 1 pulse and passes the other 0 It alternates between two unstable states 1 E7A06 What is the characteristic function of a monostable multivibrator? 0 It switches momentarily to the opposite binary state and then returns after a set time to its original state 1 It is a clock that produces a continuous square wave oscillating between 1 and 0 0 It stores one bit of data in either a 0 or 1 state 0 It maintains a constant output voltage, regardless of variations in the input voltage 0 E7A07 What logical operation does an AND gate perform? 0 It produces a logic "0" at its output only if all inputs are logic "1" 0 It produces a logic "1" at its output only if all inputs are logic "1" 1 It produces a logic "1" at its output if only one input is a logic "1" 0 It produces a logic "1" at its output if all inputs are logic "0" 0 E7A08 What logical operation does a NAND gate perform? 0 It produces a logic "0" at its output only when all inputs are logic "0" 0 It produces a logic "1" at its output only when all inputs are logic "1" 0 It produces a logic "0" at its output if some but not all of its inputs are logic "1" 0 It produces a logic "0" at its output only when all inputs are logic "1" 1 E7A09 What logical operation does an OR gate perform? 0 It produces a logic "1" at its output if any input is or all inputs are logic "1" 1 It produces a logic "0" at its output if all inputs are logic "1" 0 It only produces a logic "0" at its output when all inputs are logic "1" 0 It produces a logic "1" at its output if all inputs are logic "0" 0 E7A10 What logical operation does a NOR gate perform? 0 It produces a logic "0" at its output only if all inputs are logic "0" 0 It produces a logic "1" at its output only if all inputs are logic "1" 0 It produces a logic "0" at its output if any input is or all inputs are logic "1" 1 It produces a logic "1" at its output only when none of its inputs are logic "0" 0 E7A11 What is a truth table? 0 A table of logic symbols that indicate the high logic states of an op-amp 0 A diagram showing logic states when the digital device's output is true 0 A list of input combinations and their corresponding outputs that characterize the function of a digital device 1 A table of logic symbols that indicates the low logic states of an op-amp 0 E7A12 In a positive-logic circuit, what level is used to represent a logic 1? 0 A low level 0 A positive-transition level 0 A negative-transition level 0 A high level 1 E7A13 In a negative-logic circuit, what level is used to represent a logic 1? 0 A low level 1 A positive-transition level 0 A negative-transition level 0 A high level 0 E7B01 For what portion of a signal cycle does a Class AB amplifier operate? 0 More than 180 degrees but less than 360 degrees 1 Exactly 180 degrees 0 The entire cycle 0 Less than 180 degrees 0 E7B02 Which class of amplifier provides the highest efficiency? 0 Class A 0 Class B 0 Class C 1 Class AB 0 E7B03 Where on the load line should a bipolar-transistor, common-emitter Class A power amplifier be operated for best efficiency and stability? 0 Below the saturation region 1 Above the saturation region 0 At the zero bias point 0 Just below the thermal runaway point 0 E7B04 How can parasitic oscillations be eliminated from a power amplifier? 0 By tuning for maximum SWR 0 By tuning for maximum power output 0 By neutralization 1 By tuning the output 0 E7B05 How can even-order harmonics be reduced or prevented in transmitter amplifiers? 0 By using a push-push amplifier 0 By using a push-pull amplifier 1 By operating Class C 0 By operating Class AB 0 E7B06 What can occur when a nonlinear amplifier is used with a single-sideband phone transmitter? 0 Reduced amplifier efficiency 0 Increased intelligibility 0 Sideband inversion 0 Distortion 1 E7B07 How can a vacuum-tube power amplifier be neutralized? 0 By increasing the grid drive 0 By feeding back an in-phase component of the output to the input 0 By feeding back an out-of-phase component of the output to the input 1 By feeding back an out-of-phase component of the input to the output 0 E7B08 What is the procedure for tuning a vacuum-tube power amplifier having an output pi-network? 0 Adjust the loading capacitor to maximum capacitance and then dip the plate current with the tuning capacitor 0 Alternately increase the plate current with the tuning capacitor and dip the plate current with the loading capacitor 0 Adjust the tuning capacitor to maximum capacitance and then dip the plate current with the loading capacitor 0 Alternately increase the plate current with the loading capacitor and dip the plate current with the tuning capacitor 1 E7B09 In Figure E7-1, what is the purpose of R1 and R2? 0 Load resistors 0 Fixed bias 1 Self bias 0 Feedback 0 E7B10 In Figure E7-1, what is the purpose of C3? 0 AC feedback 0 Input coupling 0 Power supply decoupling 0 Emitter bypass 1 E7B11 In Figure E7-1, what is the purpose of R3? 0 Fixed bias 0 Emitter bypass 0 Output load resistor 0 Self bias 1 E7B12 What type of circuit is shown in Figure E7-1? 0 Switching voltage regulator 0 Linear voltage regulator 0 Common emitter amplifier 1 Emitter follower amplifier 0 E7B13 In Figure E7-1, what is the purpose of C1? 0 Decoupling 0 Output coupling 0 Self bias 0 Input coupling 1 E7B14 In Figure E7-2, what is the purpose of R? 0 Emitter load 1 Fixed bias 0 Collector load 0 Voltage regulation 0 E7B15 In Figure E7-2, what is the purpose of C2? 0 Output coupling 1 Emitter bypass 0 Input coupling 0 Hum filtering 0 E7B16 What is the purpose of D1 in the circuit shown in Figure E7-3? 0 Line voltage stabilization 0 Voltage reference 1 Peak clipping 0 Hum filtering 0 E7B17 What is the purpose of Q1 in the circuit shown in Figure E7-3? 0 It increases the output ripple 0 It provides a constant load for the voltage source 0 It increases the current-handling capability 1 It provides D1 with current 0 E7B18 What is the purpose of C2 in the circuit shown in Figure E7-3? 0 It bypasses hum around D1 1 It is a brute force filter for the output 0 To self resonate at the hum frequency 0 To provide fixed DC bias for Q1 0 E7B19 What type of circuit is shown in Figure E7-3? 0 Switching voltage regulator 0 Grounded emitter amplifier 0 Linear voltage regulator 1 Emitter follower 0 E7B20 What is the purpose of C1 in the circuit shown in Figure E7-3? 0 It resonates at the ripple frequency 0 It provides fixed bias for Q1 0 It decouples the output 0 It filters the supply voltage 1 E7B21 What is the purpose of C3 in the circuit shown in Figure E7-3? 0 It prevents self-oscillation 1 It provides brute force filtering of the output 0 It provides fixed bias for Q1 0 It clips the peaks of the ripple 0 E7B22 What is the purpose of R1 in the circuit shown in Figure E7-3? 0 It provides a constant load to the voltage source 0 It couples hum to D1 0 It supplies current to D1 1 It bypasses hum around D1 0 E7B23 What is the purpose of R2 in the circuit shown in Figure E7-3? 0 It provides fixed bias for Q1 0 It provides fixed bias for D1 0 It decouples hum from D1 0 It provides a constant minimum load for Q1 1 E7C01 How are the capacitors and inductors of a low-pass filter pi-network arranged between the network's input and output? 0 Two inductors are in series between the input and output and a capacitor is connected between the two inductors and ground 0 Two capacitors are in series between the input and output and an inductor is connected between the two capacitors and ground 0 An inductor is in parallel with the input, another inductor is in parallel with the output, and a capacitor is in series between the two 0 A capacitor is in parallel with the input, another capacitor is in parallel with the output, and an inductor is in series between the two 1 E7C02 What is an L-network? 0 A network consisting entirely of four inductors 0 A network consisting of an inductor and a capacitor 1 A network used to generate a leading phase angle 0 A network used to generate a lagging phase angle 0 E7C03 A T-network with series capacitors and a parallel (shunt) inductor has which of the following properties? 0 It transforms impedances and is a low-pass filter 0 It transforms reactances and is a low-pass filter 0 It transforms impedances and is a high-pass filter 1 It transforms reactances and is a narrow bandwidth notch filter 0 E7C04 What advantage does a pi-L-network have over a pi-network for impedance matching between the final amplifier of a vacuum-tube type transmitter and a multiband antenna? 0 Greater harmonic suppression 1 Higher efficiency 0 Lower losses 0 Greater transformation range 0 E7C05 How does a network transform one impedance to another? 0 It introduces negative resistance to cancel the resistive part of an impedance 0 It introduces transconductance to cancel the reactive part of an impedance 0 It cancels the reactive part of an impedance and changes the resistive part 1 Network resistances substitute for load resistances 0 E7C06 Which filter type is described as having ripple in the passband and a sharp cutoff? 0 A Butterworth filter 0 An active LC filter 0 A passive op-amp filter 0 A Chebyshev filter 1 E7C07 What are the distinguishing features of an elliptical filter? 0 Gradual passband rolloff with minimal stop-band ripple 0 Extremely flat response over its passband, with gradually rounded stop-band corners 0 Extremely sharp cutoff, with one or more infinitely deep notches in the stop band 1 Gradual passband rolloff with extreme stop-band ripple 0 E7C08 What kind of audio filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission? 0 A band-pass filter 0 A notch filter 1 A pi-network filter 0 An all-pass filter 0 E7C09 What characteristic do typical SSB receiver IF filters lack that is important to digital communications? 0 Steep amplitude-response skirts 0 Passband ripple 0 High input impedance 0 Linear phase response 1 E7C10 What kind of digital signal processing audio filter might be used to remove unwanted noise from a received SSB signal? 0 An adaptive filter 1 A crystal-lattice filter 0 A Hilbert-transform filter 0 A phase-inverting filter 0 E7C11 What kind of digital signal processing filter might be used in generating an SSB signal? 0 An adaptive filter 0 A notch filter 0 A Hilbert-transform filter 1 An elliptical filter 0 E7C12 Which type of filter would be the best to use in a 2-meter repeater duplexer? 0 A crystal filter 0 A cavity filter 1 A DSP filter 0 An L-C filter 0 E7C13 What is a pi-network? 0 A network consisting entirely of four inductors or four capacitors 0 A Power Incidence network 0 An antenna matching network that is isolated from ground 0 A network consisting of one inductor and two capacitors or two inductors and one capacitor 1 E7C14 What is a pi-L-network? 0 A Phase Inverter Load network 0 A network consisting of two inductors and two capacitors 1 A network with only three discrete parts 0 A matching network in which all components are isolated from ground 0 E7C15 Which type of network provides the greatest harmonic suppression? 0 L-network 0 Pi-network 0 Pi-L-network 1 Inverse Pi network 0 E7D01 What are three major oscillator circuits often used in Amateur Radio equipment? 0 Taft, Pierce and negative feedback 0 Colpitts, Hartley and Taft 0 Taft, Hartley and Pierce 0 Colpitts, Hartley and Pierce 1 E7D02 What condition must exist for a circuit to oscillate? 0 It must have a gain of less than 1 0 It must be neutralized 0 It must have positive feedback sufficient to overcome losses 1 It must have negative feedback sufficient to cancel the input 0 E7D03 How is the positive feedback coupled to the input in a Hartley oscillator? 0 Through a tapped coil 1 Through a capacitive divider 0 Through link coupling 0 Through a neutralizing capacitor 0 E7D04 How is the positive feedback coupled to the input in a Colpitts oscillator? 0 Through a tapped coil 0 Through link coupling 0 Through a capacitive divider 1 Through a neutralizing capacitor 0 E7D05 How is the positive feedback coupled to the input in a Pierce oscillator? 0 Through a tapped coil 0 Through link coupling 0 Through a neutralizing capacitor 0 Through a quartz crystal 1 E7D06 Which type of oscillator circuits are commonly used in a VFO? 0 Pierce and Zener 0 Colpitts and Hartley 1 Armstrong and deForest 0 Negative feedback and Balanced feedback 0 E7D07 Why is very stable reference oscillator normally used as part of a phase-locked loop (PLL) frequency synthesizer? 0 Any amplitude variations in the reference oscillator signal will prevent the loop from locking to the desired signal 0 Any phase variations in the reference oscillator signal will produce phase noise in the synthesizer output 1 Any phase variations in the reference oscillator signal will produce harmonic distortion in the modulating signal 0 Any amplitude variations in the reference oscillator signal will prevent the loop from changing frequency 0 E7D08 What is one characteristic of a linear electronic voltage regulator? 0 It has a ramp voltage as its output 0 The pass transistor switches from the "off" state to the "on" state 0 The control device is switched on or off, with the duty cycle proportional to the line or load conditions 0 The conduction of a control element is varied in direct proportion to the load current to maintain a constant output voltage 1 E7D09 What is one characteristic of a switching electronic voltage regulator? 0 The conduction of a control element is varied in direct proportion to the line voltage or load current 0 It provides more than one output voltage 0 The control device is switched on or off, with the duty cycle automatically adjusted to maintain a constant average output voltage 1 It gives a ramp voltage at its output 0 E7D10 What device is typically used as a stable reference voltage in a linear voltage regulator? 0 A Zener diode 1 A tunnel diode 0 An SCR 0 A varactor diode 0 E7D11 What type of linear regulator is used in applications requiring efficient use of the primary power source? 0 A constant current source 0 A series regulator 1 A shunt regulator 0 A shunt current source 0 E7D12 What type of linear voltage regulator is used in applications requiring a constant load on the unregulated voltage source? 0 A constant current source 0 A series regulator 0 A shunt current source 0 A shunt regulator 1 E7D13 Which of the following Zener diodes voltages will result in the best temperature stability for a voltage reference? 0 2.4 volts 0 3.0 volts 0 5.6 volts 1 12.0 volts 0 E7D14 What are the important characteristics of a three-terminal regulator? 0 Maximum and minimum input voltage, minimum output current and voltage 0 Maximum and minimum input voltage, maximum and minimum output current and maximum output voltage 1 Maximum and minimum input voltage, minimum output current and maximum output voltage 0 Maximum and minimum input voltage, minimum output voltage and Maximum input and output current 0 E7D15 What type of voltage regulator limits the voltage drop across its junction when a specified current passes through it in the reverse-breakdown direction? 0 A Zener diode 1 A three-terminal regulator 0 A bipolar regulator 0 A pass-transistor regulator 0 E7E01 How is an F3E FM-phone emission produced? 0 With a balanced modulator on the audio amplifier 0 With a reactance modulator on the oscillator 1 With a reactance modulator on the final amplifier 0 With a balanced modulator on the oscillator 0 E7E02 How does a reactance modulator work? 0 It acts as a variable resistance or capacitance to produce FM signals 0 It acts as a variable resistance or capacitance to produce AM signals 0 It acts as a variable inductance or capacitance to produce FM signals 1 It acts as a variable inductance or capacitance to produce AM signals 0 E7E03 How does a phase modulator work? 0 It varies the tuning of a microphone preamplifier to produce PM signals 0 It varies the tuning of an amplifier tank circuit to produce AM signals 0 It varies the tuning of an amplifier tank circuit to produce PM signals 1 It varies the tuning of a microphone preamplifier to produce AM signals 0 E7E04 How can a single-sideband phone signal be generated? 0 By using a balanced modulator followed by a filter 1 By using a reactance modulator followed by a mixer 0 By using a loop modulator followed by a mixer 0 By driving a product detector with a DSB signal 0 E7E05 What audio shaping network is added at a transmitter to proportionally attenuate the lower audio frequencies, giving an even spread to the energy in the audio band? 0 A de-emphasis network 0 A heterodyne suppressor 0 An audio prescaler 0 A pre-emphasis network 1 E7E06 What audio shaping network is added at a receiver to restore proportionally attenuated lower audio frequencies? 0 A de-emphasis network 1 A heterodyne suppressor 0 An audio prescaler 0 A pre-emphasis network 0 E7E07 What is the mixing process? 0 The elimination of noise in a wideband receiver by phase comparison 0 The elimination of noise in a wideband receiver by phase differentiation 0 The recovery of the intelligence from a modulated RF signal 0 The combination of two signals to produce sum and difference frequencies 1 E7E08 What are the principal frequencies that appear at the output of a mixer circuit? 0 Two and four times the original frequency 0 The sum, difference and square root of the input frequencies 0 The original frequencies and the sum and difference frequencies 1 1.414 and 0.707 times the input frequency 0 E7E09 What occurs in a receiver when an excessive amount of signal energy reaches the mixer circuit? 0 Spurious mixer products are generated 1 Mixer blanking occurs 0 Automatic limiting occurs 0 A beat frequency is generated 0 E7E10 What type of frequency synthesizer circuit uses a stable voltage-controlled oscillator, programmable divider, phase detector, loop filter and a reference frequency source? 0 A direct digital synthesizer 0 A hybrid synthesizer 0 A phase-locked loop synthesizer 1 A diode-switching matrix synthesizer 0 E7E11 What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter and a low-pass antialias filter? 0 A direct digital synthesizer 1 A hybrid synthesizer 0 A phase-locked loop synthesizer 0 A diode-switching matrix synthesizer 0 E7E12 What are the main blocks of a direct digital frequency synthesizer? 0 A variable-frequency crystal oscillator, phase accumulator, digital to analog converter and a loop filter 0 A stable voltage-controlled oscillator, programmable divider, phase detector, loop filter and a digital to analog converter 0 A variable-frequency oscillator, programmable divider, phase detector and a low-pass antialias filter 0 A phase accumulator, lookup table, digital to analog converter and a low-pass antialias filter 1 E7E13 What information is contained in the lookup table of a direct digital frequency synthesizer? 0 The phase relationship between a reference oscillator and the output waveform 0 The amplitude values that represent a sine-wave output 1 The phase relationship between a voltage-controlled oscillator and the output waveform 0 The synthesizer frequency limits and frequency values stored in the radio memories 0 E7E14 What are the major spectral impurity components of direct digital synthesizers? 0 Broadband noise 0 Digital conversion noise 0 Spurs at discrete frequencies 1 Nyquist limit noise 0 E7E15 What are the major spectral impurity components of phase-locked loop synthesizers? 0 Broadband noise 1 Digital conversion noise 0 Spurs at discrete frequencies 0 Nyquist limit noise 0 E7E16 What is the process of detection? 0 The masking of the intelligence on a received carrier 0 The recovery of the intelligence from a modulated RF signal 1 The modulation of a carrier 0 The mixing of noise with a received signal 0 E7E17 What is the principle of detection in a diode detector? 0 Rectification and filtering of RF 1 Breakdown of the Zener voltage 0 Mixing with noise in the transition region of the diode 0 The change of reactance in the diode with respect to frequency 0 E7E18 What does a product detector do? 0 It provides local oscillations for input to a mixer 0 It amplifies and narrows bandpass frequencies 0 It mixes an incoming signal with a locally generated carrier 1 It detects cross-modulation products 0 E7E19 How are FM-phone signals detected? 0 With a balanced modulator 0 With a frequency discriminator 1 With a product detector 0 With a phase splitter 0 E7E20 What is a frequency discriminator? 0 An FM generator 0 A circuit for filtering two closely adjacent signals 0 An automatic band-switching circuit 0 A circuit for detecting FM signals 1 E7E21 How can an FM-phone signal be produced? 0 By modulating the supply voltage to a Class-B amplifier 0 By modulating the supply voltage to a Class-C amplifier 0 By using a reactance modulator on an oscillator 1 By using a balanced modulator on an oscillator 0 E7F01 What is the purpose of a prescaler circuit? 0 It converts the output of a JK flip-flop to that of an RS flip-flop 0 It multiplies an HF signal so a low-frequency counter can display the operating frequency 0 It prevents oscillation in a low-frequency counter circuit 0 It divides an HF signal so a low-frequency counter can display the operating frequency 1 E7F02 How many states does a decade counter digital IC have? 0 2 0 10 1 20 0 100 0 E7F03 What is the function of a decade counter digital IC? 0 It produces one output pulse for every ten input pulses 1 It decodes a decimal number for display on a seven-segment LED display 0 It produces ten output pulses for every input pulse 0 It adds two decimal numbers 0 E7F04 What additional circuitry is required in a 100-kHz crystal-controlled marker generator to provide markers at 50 and 25 kHz? 0 An emitter-follower 0 Two frequency multipliers 0 Two flip-flops 1 A voltage divider 0 E7F05 If a 1-MHz oscillator is used with a divide-by-ten circuit to make a marker generator, what will the output be? 0 A 1-MHz sinusoidal signal with harmonics every 100 kHz 0 A 100-kHz signal with harmonics every 100 kHz 1 A 1-MHz square wave with harmonics every 1 MHz 0 A 100-kHz signal modulated by a 10-kHz signal 0 E7F06 What is a crystal-controlled marker generator? 0 A low-stability oscillator that sweeps through a band of frequencies 0 An oscillator often used in aircraft to determine the craft's location relative to the inner and outer markers at airports 0 A high-stability oscillator whose output frequency and amplitude can be varied over a wide range 0 A high-stability oscillator that generates a series of reference signals at known frequency intervals 1 E7F07 What type of circuit does NOT make a good marker generator? 0 A sinusoidal crystal oscillator 1 A crystal oscillator followed by a class C amplifier 0 A TTL device wired as a crystal oscillator 0 A crystal oscillator and a frequency divider 0 E7F08 What is the purpose of a marker generator? 0 To add audio markers to an oscilloscope 0 To provide a frequency reference for a phase locked loop 0 To provide a means of calibrating a receiver's frequency settings 1 To add time signals to a transmitted signal 0 E7F09 What does the accuracy of a frequency counter depend on? 0 The internal crystal reference 1 A voltage-regulated power supply with an unvarying output 0 Accuracy of the AC input frequency to the power supply 0 Proper balancing of the power-supply diodes 0 E7F10 How does a frequency counter determine the frequency of a signal? 0 It counts the total number of pulses in a circuit 0 It monitors a WWV reference signal for comparison with the measured signal 0 It counts the number of input pulses in a specific period of time 1 It converts the phase of the measured signal to a voltage which is proportional to the frequency 0 E7F11 What is the purpose of a frequency counter? 0 To indicate the frequency of the strongest input signal which is within the counter's frequency range 1 To generate a series of reference signals at known frequency intervals 0 To display all frequency components of a transmitted signal 0 To compare the difference between the input and a voltage-controlled oscillator and produce an error voltage 0 E7G01 What determines the gain and frequency characteristics of an op-amp RC active filter? 0 The values of capacitances and resistances built into the op-amp 0 The values of capacitances and resistances external to the op-amp 1 The input voltage and frequency of the op-amp's DC power supply 0 The output voltage and smoothness of the op-amp's DC power supply 0 E7G02 What causes ringing in a filter? 0 The slew rate of the filter 0 The bandwidth of the filter 0 The filter shape, as measured in the frequency domain 1 The gain of the filter 0 E7G03 What are the advantages of using an op-amp instead of LC elements in an audio filter? 0 Op-amps are more rugged and can withstand more abuse than can LC elements 0 Op-amps are fixed at one frequency 0 Op-amps are available in more varieties than are LC elements 0 Op-amps exhibit gain rather than insertion loss 1 E7G04 What type of capacitors should be used in a high-stability op-amp RC active filter circuit? 0 Electrolytic 0 Disc ceramic 0 Polystyrene 1 Paper dielectric 0 E7G05 How can unwanted ringing and audio instability be prevented in a multisection op-amp RC audio filter circuit? 0 Restrict both gain and Q 1 Restrict gain, but increase Q 0 Restrict Q, but increase gain 0 Increase both gain and Q 0 E7G06 What parameter must be selected when selecting the resistor and capacitor values for an RC active filter using an op-amp? 0 Filter bandwidth 1 Desired current gain 0 Temperature coefficient 0 Output-offset overshoot 0 E7G07 The design of a preselector involves a trade-off between bandwidth and what other factor? 0 The amount of ringing 0 Insertion loss 1 The number of parts 0 The choice of capacitors or inductors 0 E7G08 When designing an op-amp RC active filter for a given frequency range and Q, what steps are typically followed when selecting the external components? 0 Standard capacitor values are chosen first, the resistances are calculated, then resistors of the nearest standard value are used 1 Standard resistor values are chosen first, the capacitances are calculated, then capacitors of the nearest standard value are used 0 Standard resistor and capacitor values are used, the circuit is tested, then additional resistors are added to make any adjustments 0 Standard resistor and capacitor values are used, the circuit is tested, then additional capacitors are added to make any adjustments 0 E7G09 When designing an op-amp RC active filter for a given frequency range and Q, why are the external capacitance values usually chosen first, then the external resistance values calculated? 0 An op-amp will perform as an active filter using only standard external capacitance values 0 The calculations are easier to make with known capacitance values rather than with known resistance values 0 Capacitors with unusual capacitance values are not widely available, so standard values are used to begin the calculations 1 The equations for the calculations can only be used with known capacitance values 0 E7G10 What are the principal uses of an op-amp RC active filter in amateur circuitry? 0 High-pass filters used to block RFI at the input to receivers 0 Low-pass filters used between transmitters and transmission lines 0 Filters used for smoothing power-supply output 0 Audio filters used for receivers 1 E7G11 Where should an op-amp RC active audio filter be placed in an amateur receiver? 0 In the IF strip, immediately before the detector 0 In the audio circuitry immediately before the speaker or phone jack 0 Between the balanced modulator and frequency multiplier 0 In the low-level audio stages 1