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Right OPTION is (c) 2 vertical DEFLECTION PLATES

To elaborate: In a dual beam oscilloscope, there are two vertical deflection plates and two separate channels. Each channel consists of a PREAMPLIFIER and an attenuator stage.

Right answer is (B) TWO electron guns

Explanation: On the Cathode Ray Oscilloscope, two VOLTAGES can be STUDIED simultaneously by means of two electron guns generating two separate beams through a special cathode ray TUBE.

The correct CHOICE is (C) many traces

The explanation is: In a multitrace oscilloscope, a signle ELECTRON beam is used. It makes use of SEVERAL traces by SWITCHING the Y deflection plates from one input signal to the other.

Right answer is (b) False

To explain: In a dual trace oscilloscope, the square WAVE generator reproduces two signals on the screen. When the switching frequency of the square wave generator is HIGHER than that of the individual signals, the bits of each signal are provided ALTERNATELY to the vertical INPUTS.

Right option is (a) 1

The best I can explain: In a dual trace oscilloscope, the SQUARE wave GENERATOR provides alternate bias SIGNALS to the switches Q3 and Q4. When Q3 is conducting, Q4 remains off while Q3 is off, Q4 conducts.

Right answer is (d) generates alternate inputs

For EXPLANATION I would SAY: A square WAVE generator in a dual trace oscilloscope provides alternate biasing signals to the SWITCHES Q3 and Q4.

Right option is (c) R1 and R2

Easiest explanation: In a dual trace oscilloscope, the resistances R1 and R2 are used for ADJUSTING the MAGNITUDES of the amplitudes of the SIGNALS A and B of the TWO channels A and B.

Correct answer is (b) gain CONTROL stage

For EXPLANATION I WOULD SAY: In a dual trace oscilloscope, the signals are applied to the gain control as well as the gate control stage.

Correct answer is (d) Alternate mode

The best EXPLANATION: In a DUAL Trace Oscilloscope, the alternate mode of OPERATION enables to maintain the correct phase relationship between the signals from the channels A and B.

The CORRECT option is (c) T flip-flop

Easy explanation: In the Dual TRACE Oscilloscope, an ELECTRONIC switch is controlled by making use of a T flip-flop which is also known as a toggle flip-flop. Switching OCCURS during the beginning of a new sweep.

Correct option is (B) vertical and horizontal

Best EXPLANATION: In a Dual Trace OSCILLOSCOPE, X-Y mode means the oscilloscope operates from the first CHANNEL A as a vertical SIGNAL and from the second channel B as a horizontal signal.

The correct choice is (a) an electronic switch

To elaborate: In a Dual Trace OSCILLOSCOPE, after the pre amplification PROCESS is done, the signals are fed into an electronic switch. The switch passes one channel at a TIME through the delay LINE.

The correct option is (c) 2 METHODS

Explanation: In order to GENERATE two INDEPENDENT traces in a oscilloscope, two methods are used. One method is known as the SWEEP method whereas the other is known as the chop method.

Correct CHOICE is (a) True

Best explanation: In a Cathode Ray Oscilloscope, two methods are used to generate two independent traces. The FIRST method is an alternate SWEEP method while the second is the CHOP method.

The CORRECT answer is (d) 2

To elaborate: In a Dual Trace Oscilloscope, two vertical inputs EXIST. The two channels are known as A and B. A SEPARATE preamplifier and an ATTENUATOR stage exist for each channel. The amplitude of each input can be controlled separately.

The correct answer is (a) to compare more than TWO VOLTAGES

For explanation I would say: A dual trace OSCILLOSCOPE is required for COMPARISON for two or more voltages in the analysis and STUDY of electronic circuits and systems.

The correct answer is (a) dual sweep mode

Best explanation: A switches sweep mode is USED for DISPLAYING two independent VARIABLE sweep MODES in an alternative fashion. Initially, waveform is displayed with a slow sweep RATE and then with a fast sweep rate.

The correct choice is (d) STABLE output

For EXPLANATION: TTL triggering CIRCUIT in a Cathode Ray Oscilloscope gives rise to a stable display. There is no necessity to check the TTL LEVELS on the screen. The logic levels are also checked to be correct.

The correct answer is (C) PREVENTS interference

The best EXPLANATION: In a Cathode Ray Oscilloscope, TTL trigger circuit prevents sweep signals that are below the trigger gap from GETTING triggered FALSELY.

The correct choice is (b) USING TTL logic

The BEST I can EXPLAIN: In a CATHODE Ray Oscilloscope, TTL trigger circuit is used for setting the correct trigger POINTS. The trigger circuit acts in the same way as the input of a TTL circuit.

Right choice is (a) True

The explanation is: The TTL trigger mode in a CATHODE Ray Oscilloscope is USEFUL in the CASE of ringing effects. Ringing effects produce false triggering even THOUGH the trigger points may not be set.

Correct choice is (B) False

To explain I WOULD say: The TTL TRIGGER mode in a Cathode RAY Oscilloscope is useful in the case of ringing effects. Ringing effects lead to the formation of unwanted oscillations due to switching transients.

The correct answer is (c) TTL triggering

To EXPLAIN I WOULD say: In a Cathode Ray Oscilloscope, the waveform is affected as a result of TTL trigger mode. The lead inductance of the ground along with PROBE CAPACITANCE results in a RESONANCE circuit.

Correct choice is (a) 2

The BEST explanation: A CATHODE Ray Oscilloscope has TWO time base GENERATORS. A time base generator has various sweep modes based on the COMPLEXITY of the second time base generator.

Correct choice is (d) 10 times

The best EXPLANATION: In a Cathode Ray Oscilloscope, the horizontal amplifier can be EXPANDED by up to 10 times. This allows a division of 1nsec DISPLAY for very HIGH speed transient WAVEFORMS.

The CORRECT answer is (a) capacitor

The explanation is: In a Cathode Ray OSCILLOSCOPE, the sweep rate is controlled by a capacitor. This is done through MEANS of the CHARGING current flowing through the capacitor.

Correct choice is (C) linearity

The BEST I can explain: In a Cathode RAY OSCILLOSCOPE, a time base generator must have a linear RELATIONSHIP. Linearity of the order of more than 1 % across the cathode ray tube can be obtained by making use of a time base generator.

The correct option is (b) False

For explanation I would say: As a result of trigger threshold CROSSING the time base GENERATOR doesn’t immediately get ACTIVATED after the HOLD off time. This time is known as the waiting time wherein the triggering pulses cross the trigger threshold.

Right choice is (a) True

Easiest explanation: After the end of a cycle of SWEEP and retrace, the TIME base generator takes certain amount of time to COMMENCE a new cycle. This time can be divided into two PARTS:

i) Hold off time and ii) WAITING time.

Correct option is (c) used with TIME base GENERATOR

To elaborate: In a Cathode RAY Oscilloscope, the trigger CIRCUIT is basically used for triggering the time base generator. It triggers the time base generator and produces a ramp signal.

The correct OPTION is (b) TIME to activate time base generator

Explanation: In a Cathode Ray Oscilloscope, the trigger circuit produces a trigger pulse. The pulse MUST exceed a certain REFERENCE threshold level in order to activate the time base generator. This is known as trigger threshold.

Correct option is (a) time to start a ramp

For explanation: In a CATHODE RAY Oscilloscope, the trigger circuit applies the pulse as soon as the cycle ends. The hold off time in a time BASE generator is defined as the time taken for the ramp signal so as to stabilise the FLYBACK circuitry.

The correct OPTION is (a) True

The explanation: In a Cathode RAY Oscilloscope the sweep base generator produces the MOVEMENT of the SPOT on the screen. It acts as the time base for the waveforms and as a result it is known as a time base generator.

Right option is (B) capacitor

Best explanation: In a Cathode Ray Oscilloscope, the sweep generator basically WORKS on the principle of a capacitor. It generates linear rise time voltages by MAKING use of the CHARGING characteristics of a capacitor.

Right choice is (d) oscillator

To explain I would say: The TIME base generator circuit is BASICALLY a relaxation oscillator. It generates a saw tooth waveform. A BOOTSTRAP technique allows LINEARITY but is very expensive.

Correct OPTION is (c) sinusoidal WAVEFORM

For explanation I would say: In the time base generator, a linearly increasing ramp waveform that decreases to ZERO within a very short time span is used to make sure that the spot is only visible from LEFT to right direction.

Right answer is (a) True

For EXPLANATION: In a CATHODE Ray Oscilloscope, the time DEPENDENT waveforms need x-AXIS for CALIBRATION. It is calibrated as the time axis.

Correct choice is (d) spot movement

Best explanation: In a Cathode Ray OSCILLOSCOPE, the time base GENERATOR CONTROLS the rate at which the visible spot moves across the screen. Using the front panel controls this rate can be modified.

Correct choice is (c) left to RIGHT

Easiest explanation: In a CATHODE Ray OSCILLOSCOPE, a linear sweep is used to move the VISIBLE SPOT from left to right direction. The movement of the spot from right to left direction is not visible.

The correct answer is (a) SWEEP generator

Easy EXPLANATION: Time DOMAIN oscilloscopes NEED a sweep generator. The sweep generator MUST be a linear function of time for the x-axis display.

The correct answer is (B) GENERATOR

For explanation I would say: In a Cathode Ray Oscilloscope, a generator that PRODUCES a waveform REQUIRED for the MOVEMENT of the visible spot horizontally is known as the time base generator.

Right answer is (a) True

To explain: In a Cathode Ray OSCILLOSCOPE the ALTERNATE knob is used to transition between the two DIFFERENT input SIGNALS. Using the vertical POSITION control, the traces of the two input signals are separated vertically.

The correct choice is (b) inverts the INPUT

The explanation: In a Cathode RAY Oscilloscope the invert control section is USED for the purpose of inverting the input signal. It basically multiplies the input signal by a factor of -1.

Correct option is (C) 10 TIMES as normal

Easy explanation: In a Cathode Ray Oscilloscope X10 INDICATES that gain of the vertical AMPLIFIER is made 10 times that of the normal value. When the X10 switch is turned ON, scope of the CRO is et to 0.05 V/cm.

The correct option is (a) measurement

The best EXPLANATION: In a Cathode Ray Oscilloscope the SCALE illumination is BASICALLY used for the purpose of measurement. It basically illuminates the scale and as a RESULT the reading can be clearly seen.

Correct choice is (d) focus CONTROL

The best I can explain: In a Cathode Ray OSCILLOSCOPE the astigmatism FORMS ANOTHER set of focus control. A sharp spot can be obtained by the combination of focus control and astigmatism.

Right ANSWER is (c) CONTROLS sharpness

The best I can explain: In a Cathode Ray Oscilloscope the focus section controls the sharpness of the visible spot on the screen. By VARYING the voltage applied to the FOCUSSING anodes, visible spot on the screen is focussed SHARPLY.