This is a complete Electronics Engineering (Basic Electronics / EDC / Network & Devices) question paper built according to a 70-mark university pattern. The paper thoroughly covers diodes, rectifiers, BJT characteristics, FET, MOSFET, operational amplifiers, modulation, communication systems, measuring instruments, and DVM/CRO concepts.
The question paper is divided into three sections – A, B, and C, covering short conceptual questions, medium descriptive questions, and long analytical/numerical questions. Ideal for B.Tech 1st year ECE, CSE, IT, EE, EI, and related disciplines.
It is highly useful for semester exam practice, sessional exams, competitive exams, and last-minute revision.
SECTION A – Short Answer Questions (7 × 2 = 14 Marks)
This section checks basic concepts in analog electronics and communication engineering:
Output voltage of an op-amp with differential input
Ripple factor for rectifiers
Why BJT is a current-controlled device
Advantages of digital instruments over analog
Ideal characteristics of an operational amplifier
Modulation index and AM spectrum
Definition & formula of FET transconductance
These short questions help revise fundamental definitions and formulas.
SECTION B – Descriptive Questions (Attempt Any 3 × 7 = 21 Marks)
Diode Circuits
Full-wave voltage doubler
Bridge rectifier with working
BJT Characteristics
Common emitter configuration with input/output characteristics
Explanation of active, cutoff, and saturation regions
Operational Amplifiers
Op-amp as:
Integrator
Inverting summer
Voltage follower
Digital Multimeter (DMM)
Block diagram + measurement of AC, DC, and other electrical parameters
Communication System
Basic block diagram of communication system
Power saving when one sideband + carrier is suppressed (SSB-SC) with m = 1
These questions develop understanding of active devices and analog circuits.
SECTION C – Long Questions (7 Marks Each)
Q3 – Zener Diode / Special Diodes
Choose one:
Option 1
Determine Vi range for zener conduction
Find Vo for a given diode-regulated circuit
Option 2
Explain Tunnel diode
Explain diffusion and transition capacitance
Q4 – BJT Biasing / FET & MOSFET
Choose one:
Option 1
For a transistor network:
Determine RB and RE
Calculate VB, VCE, VBC
Option 2
Construction, working, characteristics of N-channel JFET
Transfer curve
Construction & working of depletion MOSFET
Q5 – Op-Amp Characteristics / Gain Derivation
Choose one:
Option 1
Determine output voltage of op-amp circuit
Explain:
CMRR
Slew rate
Option 2
Derive voltage gain for:
Inverting op-amp
Non-inverting op-amp
Q6 – Electronic Instruments
Choose one:
Option 1
Block diagram + working of Ramp-Type Digital Voltmeter (DVM)
Option 2
Block diagram of CRO with explanation
Lissajous figure frequency calculation (Given: tangents = 5 vertical, 6 horizontal, fₕ = 1800 Hz → find fᵥ)
Q7 – Amplitude Modulation
Choose one:
Option 1
Define AM
Derive full expression of AM wave
Derive modulation index
Option 2
Calculate modulation index from transmitted power values
With second modulating signal (m = 0.4), calculate new total radiated power
