77 terms

CTC-CST Test (1)

One advantage of the solid-state diode over the tube diode is
Small size
The point where the N-type and P-type materials touch is called
the juction
Which of the following is not a diode
What element is commonly used to make semiconductors
A diode that glows when forward biased is the
The main characteristic of any diode is
it lets current flow in only one direction
Two types of semicondutor material are
N and P
PRV stands for
peak reverse voltage
A rectifier using one diode is a
half-wave rectifier
The rectifier circuit depends on the operation of what part
An advantage of the bridge rectifier is
full-wave rectification without center-tap transformer
In a full-wave rectifier , load current flows
in one direction during both halves of the ac cycle
A simple diode conducts current when
A diode that glows when forward biased is the
The bridge rectifier uses
four diodes
Which of the following is not a diode?
PRV stands for
peak reverse voltage
The rectifier is used to change
ac to dc
What is ripple
varying direct current
What part is most common in a filter circut
A bad filter will cause an audio system to
What is a filter circuit used for
remove ripple
As compared with a half-wave rectifier, a full-wave or bridge rectifier
reduces ripple
Expensive power supplies should have
very low ripple
Use of a filter in a power supply will
increase the dc output
What instrument is used to measure ripple
ac voltmeter
A capacitor reduces ripple by
storing and releasing electrons
Filter action can be improved by
adding capacitance
The ratio of input to output is known as
A circuit used to change ac to dc is a
If load resistance changes during use, divider voltage levels will
An important fact to know when designing a voltage divider is
load resistance
A skill or area of knowledge not required when designing a voltage divider is
A multilevel voltage divider uses
two or more resistors in series
The easiest way to drop, reduce , voltage to a single load is to
place a resistor in series with the laod
The important part in a voltage divider circuit is a
The cathode on a zener diode symbol looks like
the letter Z
The equation for percent regulation is
E1-E2/E2 x 100
A power supply with very little voltage change when the load changes is said to have
good regulation
A component not used as part of a voltage regulator circuit is the
rectifier diode
An electronics circuit that keeps the output voltage from changing is a
A forward-baised zener diode has
low resistance
An electronic device that uses a well regulated power supply is a
radio transmitter
The term building blocks refers to
individual circuts
A bias supply is often used for
tube tramsmitter circuts
Power supply circut design depends mostly on
how power is to be used
Multivoltage power supply transformers have
two or more secondary windings
A floating power supply is
not connected to a common or circut point
The most expensive part of a power supply is usually the
The typical power supply does not contain an
The semiconductor type in the base of an NPN transistor is
The transistor affects the operation of a circut much as a
switch or variable resistor
Three transistor parts are
emmiter, base, collector
Current can flow in the output of a transistor only when
the input is forward biased
The transistor has largely replaced the vacuum tube because of its
small size and low heat
The arrowhead on a PNP transistor symbol points
toward the base
The order of semiconductor materials in a transistor is
A sine wave that gradually drops in amplitude is said to be
For oscillators that must have stable frequencies, the following tuned circuit is best
Sending some of the output signal to the input is
The howl in a poorly setup public address system is an example of
audio oscillation
A basic oscillator wave is
The frequency of a tuned circuit can be changed by using
variable parts
An RF oscillator makes current at
radio frequencies
Oscillators are used in electronic music instruments to make
The frequency of a tuned circuit is determined by
part values
In the colpitts oscillator, the feedback path is connected between
two capacitors
An SCR has
three leads
An SCR in an ac circuit acts much like a
diode rectifier
Current through the SCR can be stopped by
opening the circuit
An SCR can be tested with
The SCR is useful for controlling circuits with
high power
The SCR is triggered by forward bias on the
gate-cathode junction
SCR control of an ac circuit is set by the
triggering circuit
The SCR can control power in a circuit much like a
relay switch
An SCR is not used to
amplify audio signals
The SCR schematic symbol shows
gate, anode, cathode