electronics
decade counter
keeps a running tally of all pulses that pass through the main gate
primary winding
part of the transformer; coil containing the AC voltage
secondary winding
part of the transformer; coil in which the voltage is induced; the amount of induced voltage depends on the amount of mutual induction between the two coils
notations
part of transformers that represent winding polarity or phase shift; the phase of the applied voltage vs. the induced voltage.
main gate
passes conditioned input signal to the counter circuit if a time base signal is present at the same time
voltage ratio
(Ex/Ep) = (Ns/Np)
current ratio
(Ip/Is) = (Ns/Np)
impedance ratio
(Zp/Zs) = (Np/Ns)^2
impedance
The (Z) of a circuit containing both inductance and resistance is: -Total opposition to current flow by both inductor and resistor - Vector sum of the inductive reactance and the resistance in the circuit - For a series RL circuit, the impedance is Z = (square root) R^2 + XL^2
amplitude
maximum departure of the average value of an alternating wave
moving coil meter
measures DC current (must convert AC to DC)
frequency counter
measures frequency by measuring a known frequency against an input frequency
channel coupling
-DC: passes both DC and AC components of the signal waveform to the oscilloscope -AC: blocks the DC component of the input waveform and passes the AC component -GND: waveform disconnected from oscilloscope input
frequency amplitude phase duration shape
FAPDS; information provided by an oscilloscope -_________ of a signal -_________ of a signal -_____ relationship between signal waveforms -________ of a signal -_____ of a signal's waveform
maximum
Given an applied AC Voltage to a capacitive circuit whose capacitor is discharged the current in the circuit is going to be initially at a _______ because the capacitor is discharged.
drops to zero
Given an applied AC Voltage to a capacitive circuit whose capacitor is discharged: As soon as the capacitor charges to the peak applied AC voltage, the charging current _____ __ ____.
Ohm's law for capacitors
I = E/R = E/Xc
electromagnetic induction
If two electrically isolated coils are placed next to each other and an AC voltage is put across one coil: - A changing magnetic field results in that coil. - This changing magnetic field induces a voltage into the second coil - This action is called _______________ _________ - The device is called a transformer
lags
In a pure inductive circuit, the current ____ the applied voltage by 90 degrees.
left hand rule for generators (thumb, index, middle)
The polarity of induced voltage can be determined by the ____ ____ ____ ___ __________. The _____ points in the same direction as the motion of the conductor. The _____ finger points in the direction of the flux lines. The ______ finger points towards the electron current flow.
secondary
When a transformer is operated without a load there is no _________ current flow.
capacitor
When an AC voltage sine wave is applied to a _________, it is as though electrons are flowing through the circuit, however: -The capacitor is charging and discharging because of the alternating polarity of the voltage. - Depending on the frequency, the capacitor could have more time to charge up before the AC voltage sine wave reverses polarity thereby delaying the discharge current . - This opposition that the capacitor offers to the applied AC voltage, that's frequency related is called the capacitive reactance
magnetic field
When an AC voltage sine wave is applied to an inductor, it generates a current thereby creating a ________ _____.
parallel
When capacitors are connected in ________, the reciprocal of the capacitive reactance is equal to the sum of the reciprocals of the individual capacitive reactances. (1/Xct) = (1/Xc1) + (1/Xc2) + (1/Xc3)
series
When capacitors are connected in a ______, the capacitive reactance is equal to the sum of the individual capacitive reactances. Xct = Xc1 + Xc2 + Xc3
passive
_______ means that the probe will attenuate the input signal by a factor of 10.
filter
a circuit that: - Discriminates among frequencies, attenuating some frequencies while allowing others to pass - It establishes a cutoff point between frequencies that are passed and those that are attenuated - The two most common types are low-pass and high-pass.
Direct Current (DC)
a current that flows only in one direction; it doesn't pulsate, vary or alternate; it is constant
Alternating Current (AC)
a current whose direction of flow reverses with regularity; the most used method to transmit electrical energy today from one location to another
capacitor reactance
a function of the frequency of the applied voltage and the capacitance; represented by Xc and is measured in ohms; the opposition a capacitor offers to the applied AC voltage Xc = 1/2(pi)fC f = frequency in Hz C = capacitance in farads
mutual induction
an effect resulting when a magnetic field expands in the same direction as the current in the primary, aiding it and causing it to increase
oscilloscope
an electric test instrument that allows 2 dimensional observation of constantly varying signal voltages as a function of time; FAPDS
transformer
allow the transfer of an AC signal from one circuit to another. The transfer may involve: -stepping up/down the voltage -passing the voltage unchanged
low pass filter
allows low frequencies to pass with little opposition while attenuating high frequencies: -Consists of a resistor and a capacitor in series. - The input voltage is applied to both the resistor and capacitor - The output is taken from across the capacitor
coupling network
allows the AC signal to pass while blocking the DC signal
decoupling network
allows the DC signal to pass while attenuating the AC signal
effective value
amount that produces the same degree of heat energy in a given resistance as an equal amount of direct current; determined by the root mean square process (RMS)
degree of rotation
angle to which the armature has turned
phosphor screen
emits light when struck by electrons
clamp on meter
based on the principal that an AC current flowing in a conductor causes a magnetic field; uses split core transformer allowing the core to be opened and placed around the conductor
iron vane movement meter
consists of a stationary and a movable vane; pointer is attached to the movable vane which moves proportional to the current passing through the coil; the magnetic field magnetized both vanes with the same polarity causing the movable vane to pull away
signal conditioner
converts input signal to a compatible wave shape and amplitude
digital meter
current is converted into proportional voltage first and then measured; true rms value - waveform shape dependent
electron gun
generates the electron beam that strikes the screen
no voltage induced
dark and light half of loop is parallel to the lines of force; or loop rotates to a parallel position again
maximum voltage induced
dark half of loop rotated downward or upward90 degrees
turns ratio
determines whether the transformer is used to step up, step down, or pass voltage unchanged; turns ratio = Ns/Np Ns= # of turns in secondary Np= # of turns in primary
time base
drives the gate control circuit
polarity of voltage
each alternation is produced by a change in ________ __ _______.
one cycle or two alternations
each time an AC generator moves through one complete revolution it is said to complete ___ _____ or ___ ____________
0.707 Vpeak
effective (rms) value of a sine wave
horizontal and vertical deflection amplifiers
increase the amplitude of the input voltage
analog meters
meters that use d'Arsonval movement which is where a coil of wire and a magnetized field can detect flow of current in wire thereby causing a needle to proportionally deflect
horizontal deflection plate
moves the electron beam back and forth across the screen
vertical deflection plate
moves the electron beam in the vertical direction
hertz (Hz)
one cycle per second
gate control circuit
opens and closes main gate and provides a signal to latch the count at the end of the counting period
high pass filter
permits frequencies above the cut off point to pass while attenuating frequencies below the cut off point: -Consists of a capacitor and a resistor in series. - The input voltage is applied to both the resistor and capacitor - The output is taken from across the resistor
bode plotter
produces a graph of a circuit's frequency response; useful for analyzing filter circuits; horizontal axis shows frequency in Hz; vertical axis shows ratio of the circuits Vo/Vi
step up transformer
produces a secondary voltage greater than its primary voltage; always greater than 1
step down transformer
produces a secondary voltage less than its primary voltage; always less than 1
sweep generator
provides a saw-tooth waveform as input to the horizontal deflection amplifier
oscilloscope probe
provides high input impedance termination with low capacitance; measurements should be performed between the signal test point and ground; should automatically detect its attenuation factor
power supply
provides the DC voltage to operate the amplifiers and cathode ray tube
leading phase
refers to a wave that occurs "ahead" of another wave of the same frequency
lagging phase
refers to a wave that occurs "behind" another wave of the same frequency
peak value
the absolute value of a point on the waveform with the greatest amplitude
phase difference
the difference expressed in electrical degrees or time, between two waveforms having the same frequency and referenced to the same point in time
inductive reactance
the opposition to current flow offered by an inductor in AC circuit; represented by XL; a function of the frequency of the applied AC voltage and the inductance; measured in ohms XL = 2(pi)fL f = frequency in Hz L= inductance in henries
phase
the position of a point in time (instant) on a waveform cycle; sometimes expressed in radians where one radian of phase equals 57.3^0
rectification
the process of converting AC to DC; convert the sine wave into a pulsating DC current that is applied to the meter movement
synchronizing circuit
the trigger section that controls the start event of the sweep
peak to peak value
the vertical distance between 2 peaks
f = 1/t t = 1/f
time and frequency relationship (2 equations)
Resistor-Capacitor (RC) Networks
used for filtering, decoupling, DC blocking, or coupling phase-shift circuits
phase shift network
used for phase shifting applications of 60 degrees or less