Amplitude modulation voltage is produced by a circuit that can _______the carrier by the modulating signal
multiply
100
_______________ modulator is a low level AM modulator consisting of a resistive mixing network, a diode rectifier, and an LC tuned circuit.
diode
100
PIN diodes are special type silicon junction diodes designed for use at frequencies above 100 MHz.
When PIN diodes are forward-biased, they operate as__________.
variable resistors
100
PIN diodes are a special type of germanium diode for use at frequencies approximately below 100 MHz.
above
100
The ________ method of SSB generation uses a phase shift technique that causes the sidebands to be cancelled out
phasing
200
Circuits that accept modulated signals and recover the original modulating information are called
demodulator detector
200
__________________modulator consists of a resistive mixing network, a transistor, and an LC tuned circuit. The emitter-base junction of the transistor serves as a diode and nonlinear device.
transistor
200
For diode and transistor modulators, ________________ oscillates to supply the needed missing half cycles of the AM output.
LC tuned circuit
200
One way to generate the product of the carrier and modulating signal is to apply both signals to a linear component or circuit.
non linear
200
___________________ use an internal clock signal at the carrier frequency in the receiver to switch the AM signal off and on, producing rectification similar to that in a standard diode detector.
Synchronous detectors
300
A circuit that generates a DSB signal, suppresses the carrier and leaves only sum and difference frequencies at the output is the
balanced modulator
300
The _________ modulator consists of an input transformer, an output transformer and four diodes connected in a bridge circuit. The carrier signal is applied to the center taps of the input and output transformers. The modulating signal is applied to the input transformer.
Lattice
300
In high-level AM, the modulator varies the voltage and power in the __________
final RF amplifier
300
A diode modulator is used rather than a transistor modulator because the diode circuit provides gain.
transistor
300
__________ is a type of integrated circuit that can be used as a balanced modulator which uses differential amplifiers operating in the linear mode.
analog multiplier
400
The output of a balanced modulator is
DSBSC
400
__________________modulator is a linear power amplifier that takes the low-level modulating signals and amplifies them to a high-power level. A modulating output signal is coupled through a modulation transformer to a class C amplifier.
collector
400
In transistor modulation ,the emitter-base junction of the transistor serves as a diode and nonlinear device.
Modulation and amplification occur as ________controls a larger collector current.
base current
400
One of the more complicated high-level amplitude modulators is the diode modulator.
low level
400
______________ modulator make excellent amplitude modulators because they have a high gain, good linearity and can be 100 percent modulated.
differential amplifier
500
________modulators generate AM with small signals and must be amplified before transmission.
low level
500
__________________produces high-level modulation without a large and expensive modulation transformer used in collector modulators. It improves frequency response.
series
500
A series modulator replaces the modulation transformer with an___________. The modulating signal is applied to it and is in series with the collector supply voltage.
emitter follower
500
The simplest and most widely used method of generating SSB signals is the Phasing method.
Filter Method
500
To recover the intelligence in a DSB or SSB signal, the carrier that was suppressed at the receiver must be reinserted and a _______________ which is a balanced modulator used in a receiver to recover the modulating signal.