BSNL JTO Previous Year Papers 2026 – Topic Analysis & Pattern-Based Practice Questions
Bharat Sanchar Nigam Limited (BSNL) conducts the Junior Telecom Officer (JTO) examination at irregular intervals whenever vacancies arise. Papers from 2007, 2009, 2013, 2016, 2018, 2022, and 2024 are publicly available through platforms such as Testbook, Adda247, and IAS Exam Portal. Studying these papers tells you exactly which topics the paper-setter has repeatedly tested, how difficulty levels have evolved, and where 5G and optical-fibre questions are now creeping in. If you are preparing for the next BSNL JTO cycle in 2026, this is the single most efficient starting point.
Sources: testbook.com, adda247.com, iasexamportal.com. Practice questions below are pattern-based and are NOT official BSNL papers.
BSNL JTO 2026 Complete Prep Series:
Why Previous Year Papers Matter for BSNL JTO 2026
BSNL JTO is one of India's most sought-after government telecom jobs. The selection process is entirely exam-based — there is no interview — so your paper score alone determines your fate. Previous year papers serve three critical functions:
- Topic weighting: Certain topics (Computer Networks, Analog Circuits, Communication Systems) appear consistently across all seven exam years. This pattern is almost certainly not coincidental.
- Difficulty calibration: Sections 1 and 2 are broadly at GATE level. A candidate who underestimates this and prepares only for SSC-level difficulty will struggle.
- Negative marking awareness: With −1 per wrong answer, knowing which question types are deceptive helps you decide when to attempt and when to skip — a skill PYQ practice builds naturally.
The 2022 and 2024 papers showed a clear uptick in 5G, optical-fibre, and mobile communication questions (from ~5Q to 7Q in Section 2). Ignoring these emerging topics in 2026 prep would be a strategic mistake.
BSNL JTO Exam History (2007–2024)
| Year |
Total Questions |
Duration |
Key Format Note |
| 2007 |
200 |
3 hrs |
Single paper, heavy analogue emphasis |
| 2009 |
200 |
3 hrs |
Similar to 2007; digital electronics increased |
| 2013 |
200 |
3 hrs |
Networks (TCP/IP) section expanded; OS added |
| 2016 |
200 |
3 hrs |
Three sections formalised; mobile comm introduced |
| 2018 |
200 |
3 hrs |
LTE/4G questions added; optical fibre grows |
| 2022 |
200 |
3 hrs |
5G numerology mentioned; data comm increases |
| 2024 |
200 |
3 hrs |
Highest 5G/optical share yet; negative marking unchanged |
Paper structure across all years: Section 1 (50Q technical/engineering) + Section 2 (50Q networking/IT) + Section 3 (20Q General Ability) + remaining questions from telecom domain concepts. Total marks: 200. Negative marking: −1/wrong answer.
Section 1 – Technical Engineering: Topic Frequency Table
Section 1 covers core electrical and electronics engineering topics at GATE level. The table below shows approximate question counts per topic based on analysis of papers from 2007 to 2024 (sources: Testbook, Adda247, IAS Exam Portal).
| Topic |
Questions (per 50) |
Difficulty |
Trend (2022–24) |
| Computer Networks |
8–10 |
High |
Stable |
| Analog Circuits |
6–8 |
High |
Slight decrease |
| Communication Systems |
6–8 |
High |
Stable |
| Digital Electronics |
5–7 |
Medium–High |
Stable |
| Signals & Systems |
5–7 |
High |
Stable |
| Electromagnetic Theory |
4–5 |
High |
Stable |
| Electronic Devices & Circuits |
3–4 |
Medium |
Slight decrease |
| Microprocessors & Microcontrollers |
3–4 |
Medium |
Stable |
Strategy: Computer Networks, Analog Circuits, and Communication Systems together contribute 20–26 questions out of 50 in Section 1. Master these three topics first. Signals & Systems and Digital Electronics are high-return topics if you have a GATE background.
Section 2 – Networking & IT: Topic Frequency Table
Section 2 focuses on networking protocols, mobile communications, and software engineering. The 5G and optical-fibre share has grown significantly since 2018.
| Topic |
Questions (per 50) |
Difficulty |
Trend (2022–24) |
| Computer Networks / TCP-IP |
10–12 |
High |
Stable |
| Data Communication |
6–8 |
Medium–High |
Increasing |
| Mobile Communications (GSM/CDMA/4G/5G) |
5–7 |
Medium–High |
Fast increasing |
| OS & Software Engineering |
5–6 |
Medium |
Stable |
| Database Management Systems |
3–4 |
Medium |
Stable |
| Optical Fibre Communication |
2–4 |
Medium–High |
Fast increasing |
Section 3 – General Ability: Topic Frequency Table
Section 3 is the easiest section and should be used to secure safe marks. Negative marking still applies, so do not guess blindly in Reasoning or Current Affairs.
| Topic |
Questions (per 20) |
Difficulty |
| English Grammar & Comprehension |
6–8 |
Easy–Medium |
| Current Affairs (Telecom sector focus) |
5–6 |
Easy–Medium |
| Logical Reasoning |
4–5 |
Easy–Medium |
| Numerical Ability |
2–3 |
Easy |
Rising Trend: 5G, Optical Fibre & Mobile Communication Topics
Between 2007 and 2016, mobile communications accounted for roughly 3–4 questions in Section 2. By 2022 that number had risen to 6–7 questions, and the 2024 paper included specific questions on 5G NR (New Radio) numerology, mmWave propagation, and optical-fibre dispersion modes — topics that were entirely absent before 2018.
For 2026 preparation, you should budget dedicated time for:
- 5G architecture: gNB, AMF, UPF, NSSF, network slicing
- 5G NR numerology: subcarrier spacing, OFDM frame structure
- CDMA vs GSM vs LTE vs 5G NR: access methods, handover, capacity
- Optical fibre: single-mode vs multi-mode, dispersion types, DWDM, splicing loss
- SDH/SONET hierarchy and OTN framing concepts
These topics carry 7–11 questions combined in recent papers and are only going to grow. A candidate who can answer 8 of these correctly while others guess has a significant scoring advantage.
Pattern-Based Practice Questions (NOT Official BSNL Papers)
Important: The following questions are original practice questions modelled on the topic distribution and difficulty level observed in BSNL JTO papers from 2007–2024. They are NOT reproduced from official BSNL question papers.
Q1 [Section 1 – Computer Networks]
In a network using CSMA/CD, what is the minimum frame size if the propagation delay between the two farthest stations is 25 μs and the transmission speed is 10 Mbps?
Show Answer & Explanation
Answer: 500 bits (62.5 bytes, rounded up to 64 bytes in Ethernet).
Minimum frame size = 2 × propagation delay × transmission rate = 2 × 25 × 10⁻⁶ × 10 × 10⁶ = 500 bits. Ethernet rounds this to 512 bits (64 bytes) as the minimum frame size.
Q2 [Section 1 – Analog Circuits]
An op-amp integrator uses R = 10 kΩ and C = 1 μF. If the input is a 2 V DC step, what is the rate of change of the output voltage?
Show Answer & Explanation
Answer: −0.2 V/ms (i.e., −200 V/s).
dVout/dt = −Vin / (RC) = −2 / (10×10³ × 1×10⁻⁶) = −200 V/s = −0.2 V/ms. The negative sign indicates the output ramps downward for a positive input.
Q3 [Section 1 – Communication Systems]
A DSB-SC signal has a carrier frequency of 1 MHz and a message bandwidth of 5 kHz. What is the bandwidth of the transmitted signal?
Show Answer & Explanation
Answer: 10 kHz.
DSB-SC bandwidth = 2 × message bandwidth = 2 × 5 kHz = 10 kHz. This is the same as standard AM — the carrier suppression does not affect bandwidth, only power efficiency.
Q4 [Section 1 – Digital Electronics]
Simplify the Boolean expression: F = A'B + AB' + AB using a Karnaugh map.
Show Answer & Explanation
Answer: F = A + B.
The expression covers minterms (0,1), (1,0), and (1,1) — i.e., all combinations except (0,0). In SOP this is A + B. On a 2-variable K-map, grouping the three cells gives A + B directly.
Q5 [Section 1 – Signals & Systems]
The Laplace transform of a unit ramp function r(t) = t·u(t) is:
Show Answer & Explanation
Answer: 1/s².
The unit ramp r(t) = t·u(t) has Laplace transform 1/s². This follows from integration property: L{t·u(t)} = (1/s)·L{u(t)} = (1/s)·(1/s) = 1/s². ROC: Re(s) > 0.
Q6 [Section 1 – Electromagnetic Theory]
The depth of penetration (skin depth) of an electromagnetic wave in a conductor is inversely proportional to:
Show Answer & Explanation
Answer: Square root of frequency (√f).
Skin depth δ = √(2/ωμσ) = √(1/πfμσ). So δ ∝ 1/√f. Higher frequency → shallower penetration. This is why high-frequency signals travel only on the surface of conductors.
Q7 [Section 2 – Computer Networks/TCP-IP]
Which TCP congestion control mechanism reduces the congestion window to 1 MSS when a timeout occurs?
Show Answer & Explanation
Answer: Slow Start (triggered on timeout).
On a timeout event, TCP resets cwnd to 1 MSS and ssthresh to half the previous cwnd, then re-enters Slow Start. This is more aggressive than the duplicate-ACK response which only halves the cwnd.
Q8 [Section 2 – Mobile Communications]
In GSM, what is the duration of one TDMA frame?
Show Answer & Explanation
Answer: 4.615 ms.
A GSM TDMA frame contains 8 time slots, each 577 μs long. Total frame duration = 8 × 577 μs ≈ 4.615 ms. This is a frequently tested numerical in BSNL papers due to BSNL's own GSM network operations.
Q9 [Section 2 – 5G/Mobile Communications]
In 5G NR, what is the minimum subcarrier spacing used in FR1 (sub-6 GHz) frequency range?
Show Answer & Explanation
Answer: 15 kHz.
5G NR uses flexible numerology (μ = 0 to 4). For μ = 0, subcarrier spacing = 15 kHz — the same as LTE. FR1 supports μ = 0, 1, 2 (i.e., 15, 30, 60 kHz). FR2 (mmWave) additionally supports 120 and 240 kHz spacing.
Q10 [Section 2 – Optical Fibre]
Which type of dispersion in single-mode optical fibre limits transmission bandwidth due to different wavelengths traveling at different speeds?
Show Answer & Explanation
Answer: Chromatic Dispersion (CD).
Chromatic dispersion includes both material dispersion and waveguide dispersion. In single-mode fibre, modal dispersion is absent; chromatic dispersion is the dominant bandwidth-limiting factor. Dispersion-shifted fibres (DSF) are designed to minimize CD near 1550 nm.
Q11 [Section 2 – Data Communication]
Calculate the Nyquist capacity of a noiseless channel with bandwidth 4 kHz and 8 signal levels.
Show Answer & Explanation
Answer: 24,000 bps.
Nyquist capacity = 2 × B × log₂(M) = 2 × 4000 × log₂(8) = 2 × 4000 × 3 = 24,000 bps. This assumes an ideal noiseless channel. For noisy channels, Shannon capacity applies.
Q12 [Section 3 – English]
Choose the grammatically correct sentence:
(A) Neither the manager nor the employees was present.
(B) Neither the manager nor the employees were present.
(C) Neither the manager nor the employees are was present.
(D) Neither the manager nor the employee were present.
Show Answer & Explanation
Answer: (B).
With "neither…nor," the verb agrees with the subject closest to it. Here "employees" (plural) is closest, so "were" is correct. Option A is wrong because it uses singular "was" with plural "employees."
Q13 [Section 3 – Current Affairs / Telecom]
BSNL's nationwide 4G rollout uses equipment from which Indian vendor under the Atmanirbhar Bharat initiative?
Show Answer & Explanation
Answer: TCS (Tata Consultancy Services) in consortium with C-DOT and Tejas Networks.
BSNL's 4G (and planned 5G upgrade) network is being built using indigenous equipment developed by the TCS-led consortium, aligned with the government's push for domestic telecom technology. This is a recurring current-affairs topic in recent BSNL papers.
Q14 [Section 1 – Microprocessors]
In the 8085 microprocessor, which interrupt has the highest priority?
Show Answer & Explanation
Answer: TRAP (Non-maskable interrupt).
8085 interrupt priority order (highest to lowest): TRAP → RST 7.5 → RST 6.5 → RST 5.5 → INTR. TRAP is both edge- and level-triggered and cannot be disabled by software.
Negative Marking Strategy: When to Attempt, When to Skip
BSNL JTO carries a penalty of −1 mark per wrong answer. This means every incorrect answer costs you 2 marks relative to a correct answer (you lose 1, the correct answer was +1). Here is a clear decision framework:
| Confidence Level |
Action |
Reasoning |
| 80%+ sure of answer |
Always attempt |
Expected value is positive |
| Can eliminate 2 of 4 options |
Attempt cautiously |
50% chance on remaining 2 = expected value neutral to slightly positive |
| Can eliminate only 1 option |
Skip |
1/3 chance = expected value negative (−0.33) |
| Pure guessing (no elimination) |
Always skip |
25% chance = expected value −0.5 per question |
Section-specific advice:
- Section 1 & 2 (technical): Many questions involve formulas. If you can set up the formula but are unsure of arithmetic, work it out rather than guessing. Avoid skipping numerical questions you partially know — work them.
- Section 3 (General Ability): English grammar questions are mostly elimination-friendly. Attempt those confidently. Skip current-affairs questions where you genuinely have no context.
How to Access BSNL JTO Official Question Papers
BSNL does not publish an official question bank on its portal (bsnl.co.in). However, past papers are available through the following routes:
- Testbook.com — Free and paid BSNL JTO PYQ PDFs; year-wise filters available.
- Adda247.com — BSNL JTO section-wise PDFs; also offers mock tests modelled on PYQ patterns.
- IAS Exam Portal (iasexamportal.com) — Text versions of older papers (2007–2016) with solutions.
- BSNL official notice archives: After each exam, BSNL sometimes releases answer keys via official circulars. Check bsnl.co.in > Careers > Exam Notices after each exam date.
- RTI route: Candidates have obtained question papers via RTI (Right to Information) applications to BSNL HQ, New Delhi. This is slower but occasionally yields papers not available elsewhere.
30-Day PYQ-Based Study Strategy
This plan assumes 4–5 hours of study per day and is designed around the PYQ topic frequency data above.
| Week |
Focus Area |
Daily Task |
| Week 1 |
Computer Networks (Sec 1 & 2 overlap) + TCP/IP deep dive |
Study 1 sub-topic; solve 15–20 PYQ questions from that sub-topic |
| Week 2 |
Analog Circuits + Communication Systems + Signals & Systems |
Formula sheet for each topic; 10 numerical practice daily |
| Week 3 |
Mobile Comm (GSM/4G/5G) + Optical Fibre + Data Communication |
Focus on fast-growing topics; 5G architecture notes + 10 Qs daily |
| Week 4 |
Full mock tests + Section 3 + Revision |
2 full mocks per week; analyse wrong answers; revise weak areas; GA daily |
Daily Section 3 routine (30 minutes): Read one telecom current-affairs article (Economic Times Telecom, Telecom Talk), do 5 English grammar questions, 3 reasoning puzzles. This small daily investment builds a consistent GA score without disrupting your technical prep.
Frequently Asked Questions (FAQs)
Q: Are BSNL JTO PYQs officially released by BSNL?
BSNL does not maintain a public question bank. Papers circulate via Testbook, Adda247, and IAS Exam Portal. Some candidates have obtained them through RTI. After examinations, BSNL sometimes releases provisional answer keys on bsnl.co.in, which serve as the most authentic reference.
Q: How many questions appeared from Computer Networks across all BSNL JTO exams?
Computer Networks (including TCP/IP protocols) is the highest-weighted topic across both Section 1 and Section 2 combined. In Section 1 alone, 8–10 questions typically come from networking concepts. Section 2 adds another 10–12. Together, this can mean 18–22 questions from networking-related topics in a 200-question paper — making it the single most important area to master.
Q: Is BSNL JTO at GATE level of difficulty?
Sections 1 and 2 are broadly at GATE level. Questions involve numerical calculations, protocol knowledge, and circuit analysis that go well beyond basic SSC or state-level exam difficulty. Section 3 (General Ability) is genuinely easy and comparable to SSC/banking exams. A candidate with a GATE preparation background typically finds Sections 1 and 2 manageable, while those without a strong engineering foundation need focused preparation.
Q: How much has the share of 5G questions grown in BSNL JTO papers?
Before 2018, 5G-related questions were absent from BSNL JTO papers. The 2022 paper introduced 5G in passing (within mobile communication context), and the 2024 paper had questions specifically on 5G NR numerology and mmWave characteristics. For 2026, candidates should expect 3–5 dedicated 5G questions in Section 2, based on this trajectory.
Q: What is the best resource for BSNL JTO PYQ practice in 2026?
Testbook and Adda247 offer structured BSNL JTO mock tests with year-wise PYQ access. For older papers (2007–2013), IAS Exam Portal has free PDF versions. After exhausting PYQs, supplementing with GATE Electronics & Communication Engineering previous year papers is highly effective for Sections 1 and 2, given the similarity in difficulty and topics.
Q: Should I attempt all 200 questions in the BSNL JTO exam?
No — with −1 negative marking, attempting questions you are genuinely unsure about is mathematically harmful. Based on PYQ analysis, a typical high-scorer attempts 150–165 questions confidently and scores 130–145, rather than attempting all 200 and getting 120–125 after penalties. Quality of attempts matters far more than quantity.
Ready to Complete Your BSNL JTO Prep?
