The Victory Key
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The official UPSC question paper of every DCIO/Tech Recruitment Test since 2022, the answer keys UPSC has released, and our question-by-question topic analysis of the 2025 and 2026 papers. Updated 24-10-2026.
Official PDFs
Links go straight to upsc.gov.in. UPSC has released each answer key only after that cycle's final result.
| Year | Test date | Advt. (posts) | Format | Question paper | Answer key |
|---|---|---|---|---|---|
| 2026 | 11 Oct 2026 | 06/2026 (6) | 100 × 3 marks | DCIO Tech 2026 paper (PDF) | Not published yet (checked 24 Oct 2026) |
| 2025 | 5 Oct 2025 | 07/2025 (13) | 100 × 3 marks | DCIO Tech 2025 paper (PDF) | Not published yet (checked 24 Oct 2026) |
| 2024 | 20 Oct 2024 | 10/2024 (9) | 120 × 2.5 marks | DCIO Tech 2024 paper (PDF) | Official key (PDF) |
| 2023 | 5 Nov 2023 | 24/2022 and 15/2023 (4 + 4) | 120 × 2.5 marks | DCIO Tech 2023 paper (PDF) | Official key (PDF) |
| 2022 | 16 Oct 2022 | 12/2021 (10) | 120 × 2.5 marks | DCIO Tech 2022 paper (PDF) | Official key (PDF) |
Solved versions with explanations are in the DCIO/Tech PDF library.
Topic-wise analysis
Our classification of every question against UPSC's 13-topic syllabus. UPSC publishes no weightage, so these counts are the best guide to what the next paper will look like.
| Syllabus topic | Side | 2025 | 2026 | Change |
|---|---|---|---|---|
| Engineering Aptitude | Aptitude | 16 | 10 | -6 |
| Electronic Devices and Circuits | Electronics | 6 | 14 | +8 |
| Digital Electronics | Electronics | 6 | 6 | 0 |
| Computer Programming and Data Structures | Computing | 6 | 10 | +4 |
| Analog and Digital Communications | Electronics | 12 | 12 | 0 |
| Microwave Engineering, RADAR Systems | Electronics | 6 | 7 | +1 |
| Satellite Communications | Electronics | 6 | 0 | -6 |
| Signals and Systems, DSP | Electronics | 12 | 10 | -2 |
| Computer Organization and Operating Systems | Computing | 5 | 6 | +1 |
| Computer Networks and Cyber Security | Computing | 10 | 6 | -4 |
| Wireless Communications and Networking | Electronics | 3 | 7 | +4 |
| Artificial Intelligence | Computing | 6 | 6 | 0 |
| Internet of Things | Computing | 6 | 6 | 0 |
| Total | 100 | 100 |
Question types (our count)
Difficulty is our judgement for a B.Tech ECE/CSE graduate.
Percent of the paper, because 2022–2024 had 120 questions and 2025–2026 had 100.
| Topic | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|
| Engineering Aptitude | 8.3% | 8.3% | 6.7% | 16.0% | 10.0% |
| Electronic Devices and Circuits | 7.5% | 6.7% | 6.7% | 6.0% | 14.0% |
| Digital Electronics | 6.7% | 6.7% | 6.7% | 6.0% | 6.0% |
| Computer Programming and Data Structures | 5.8% | 8.3% | 6.7% | 6.0% | 10.0% |
| Analog and Digital Communications | 8.3% | 9.2% | 14.2% | 12.0% | 12.0% |
| Microwave Engineering, RADAR Systems | 13.3% | 4.2% | 6.7% | 6.0% | 7.0% |
| Satellite Communications | 0.8% | 4.2% | 5.8% | 6.0% | 0.0% |
| Signals and Systems, DSP | 15.8% | 12.5% | 13.3% | 12.0% | 10.0% |
| Computer Organization and Operating Systems | 6.7% | 8.3% | 6.7% | 5.0% | 6.0% |
| Computer Networks and Cyber Security | 7.5% | 14.2% | 10.0% | 10.0% | 6.0% |
| Wireless Communications and Networking | 5.8% | 0.8% | 3.3% | 3.0% | 7.0% |
| Artificial Intelligence | 6.7% | 8.3% | 6.7% | 6.0% | 6.0% |
| Internet of Things | 6.7% | 8.3% | 6.7% | 6.0% | 6.0% |
At least 8 of the 100 questions in the 2026 paper repeat earlier papers almost word for word. These are the repeats we noticed while reading; there are probably more.
| Q | Topic | Subtopic | What it asks (our summary) | Type | Level |
|---|---|---|---|---|---|
| 1 | Electronic Devices and Circuits | Diode characteristics | Temperature step that doubles silicon reverse current | conceptual | Easy |
| 2 | Electronic Devices and Circuits | Diode characteristics | Maximum working temperature of silicon diodes | conceptual | Easy |
| 3 | Electronic Devices and Circuits | Zener diode | True statement about Zener diodes | conceptual | Medium |
| 4 | Electronic Devices and Circuits | BJT biasing & operation | Junction bias conditions for active region | conceptual | Easy |
| 5 | Electronic Devices and Circuits | BJT biasing & operation | Typical VCE range of an active-region amplifier | conceptual | Medium |
| 6 | Electronic Devices and Circuits | BJT biasing & operation | Temperature coefficient of base-emitter voltage | conceptual | Easy |
| 7 | Electronic Devices and Circuits | FET/MOSFET | VMOS versus planar MOSFET comparison | conceptual | Medium |
| 8 | Electronic Devices and Circuits | BJT small-signal amplifiers | Nature and range of BJT amplifier impedances | conceptual | Medium |
| 9 | Electronic Devices and Circuits | Amplifier frequency response (Miller) | Where the Miller capacitance is connected | conceptual | Easy |
| 10 | Electronic Devices and Circuits | Op-amps (CMRR) | Op-amp output with differential and common-mode inputs | numerical | Medium |
| 11 | Digital Electronics | Boolean algebra & K-maps | Which don't-care cell yields the given simplification | numerical | Medium |
| 12 | Digital Electronics | Boolean algebra & K-maps | Definition of an implicant | conceptual | Easy |
| 13 | Digital Electronics | Flip-flops | Characteristic equation of a T flip-flop | conceptual | Easy |
| 14 | Digital Electronics | Flip-flops | Next state of an active-low JK flip-flop | conceptual | Medium |
| 15 | Digital Electronics | Asynchronous sequential circuits | When a race condition occurs | conceptual | Medium |
| 16 | Electronic Devices and Circuits | BJT biasing & operation | Collector current including the leakage term | numerical | Easy |
| 17 | Digital Electronics | Flip-flops | JK excitation for a 1-to-0 transition | conceptual | Easy |
| 18 | Electronic Devices and Circuits | BJT small-signal amplifiers | Definition of h_re in CE configuration | conceptual | Medium |
| 19 | Electronic Devices and Circuits | BJT biasing & operation | Collector current with the base open | numerical | Easy |
| 20 | Electronic Devices and Circuits | Wave-shaping (clampers) | Definition of clamping | conceptual | Easy |
| 21 | Signals and Systems, DSP | Convolution & deconvolution | Impulse response from an input-output pair | numerical | Easy |
| 22 | Signals and Systems, DSP | Convolution & deconvolution | Input from output and impulse response | numerical | Easy |
| 23 | Signals and Systems, DSP | Convolution & deconvolution | Impulse response via the z-domain product | numerical | Easy |
| 24 | Signals and Systems, DSP | Convolution & deconvolution | Input via the z-domain product | numerical | Easy |
| 25 | Signals and Systems, DSP | LTI system properties & stability | Cascade output for a cosine through two LTI blocks | numerical | Hard |
| 26 | Signals and Systems, DSP | Fourier series & transform | Conditions for a Fourier transform to exist | conceptual | Easy |
| 27 | Analog and Digital Communications | Analog modulation | Main practical drawback of AM | conceptual | Easy |
| 28 | Analog and Digital Communications | Analog modulation | VSB transmission bandwidth formula | conceptual | Easy |
| 29 | Analog and Digital Communications | PCM & sampling | Filter applied before sampling | conceptual | Easy |
| 30 | Analog and Digital Communications | Line coding | Code using split positive-negative half pulses | conceptual | Easy |
| 31 | Analog and Digital Communications | Digital receivers (matched filter, sync) | Frequency response of a matched filter | conceptual | Medium |
| 32 | Analog and Digital Communications | Information theory & capacity | Shannon limit on Eb/N0 | conceptual | Medium |
| 33 | Analog and Digital Communications | Information theory & capacity | Definition of spectral bit rate | conceptual | Easy |
| 34 | Analog and Digital Communications | Information theory & capacity | Example of a power-limited wideband channel | conceptual | Medium |
| 35 | Wireless Communications and Networking | Fading & multipath | Channel parameter that sets codeword length under fading | conceptual | Medium |
| 36 | Microwave Engineering, RADAR Systems | Microwave resonators | Unloaded Q of a half-wave shorted line resonator | conceptual | Medium |
| 37 | Microwave Engineering, RADAR Systems | Couplers & hybrids | Power at the isolated port of an ideal hybrid | numerical | Easy |
| 38 | Microwave Engineering, RADAR Systems | Microwave filters | Purpose of Kuroda identities | conceptual | Medium |
| 39 | Microwave Engineering, RADAR Systems | Ferrite devices | Wave pair behind Faraday rotation | conceptual | Medium |
| 40 | Microwave Engineering, RADAR Systems | Microwave amplifier design | Smith-chart tool for a target noise figure | conceptual | Medium |
| 41 | Analog and Digital Communications | Analog modulation | Bandwidth saved by SSB over AM | numerical | Medium |
| 42 | Analog and Digital Communications | Analog modulation | Transconductance for an FET reactance modulator | numerical | Hard |
| 43 | Analog and Digital Communications | Analog modulation | Equivalent capacitance and reactance of a reactance modulator | numerical | Hard |
| 44 | Microwave Engineering, RADAR Systems | EM waves & reflection | Lowest frequency giving a field null at 15 cm | numerical | Medium |
| 45 | Microwave Engineering, RADAR Systems | Transmission lines & matching | Reflection coefficient for a complex load | numerical | Easy |
| 46 | Signals and Systems, DSP | Fourier series & transform | DC term of cosine to the fourth power | numerical | Medium |
| 47 | Signals and Systems, DSP | Sampling, anti-aliasing & reconstruction | Aliasing level at cutoff with a Butterworth filter | numerical | Hard |
| 48 | Signals and Systems, DSP | Sampling, anti-aliasing & reconstruction | Aliasing level at 1 kHz | numerical | Hard |
| 49 | Signals and Systems, DSP | Sampling, anti-aliasing & reconstruction | Zero-order-hold droop at 3.4 kHz | numerical | Hard |
| 50 | Analog and Digital Communications | Analog modulation | Power saved by SSB-SC at m = 0.5 | numerical | Medium |
| 51 | Computer Organization and Operating Systems | Pipelining & hazards | Hazard type when writes happen out of order | conceptual | Medium |
| 52 | Computer Organization and Operating Systems | Pipelining & hazards | Branch handling by duplicating the pipeline front end | conceptual | Medium |
| 53 | Computer Organization and Operating Systems | Multithreading | Multithreading that switches thread every cycle | conceptual | Medium |
| 54 | Computer Organization and Operating Systems | Memory (SRAM/DRAM) | Circuit that holds a bit in SRAM | conceptual | Easy |
| 55 | Computer Organization and Operating Systems | Memory (SRAM/DRAM) | Fraction of time spent on DRAM refresh | numerical | Easy |
| 56 | Computer Organization and Operating Systems | Data representation | Bit width of standard ASCII | conceptual | Easy |
| 57 | Computer Networks and Cyber Security | Reference models (OSI vs TCP/IP) | OSI layer absent from the TCP/IP model | conceptual | Easy |
| 58 | Computer Networks and Cyber Security | Delay & performance | Round-trip delay through a high satellite | numerical | Easy |
| 59 | Computer Networks and Cyber Security | Physical layer & data rate limits | Nyquist bit rate for a 4-level signal | numerical | Easy |
| 60 | Computer Networks and Cyber Security | Data link (flow control/ARQ) | Name for carrying ACKs on data frames | conceptual | Easy |
| 61 | Computer Networks and Cyber Security | Ethernet & LANs | False claim about jumbo frames | conceptual | Easy |
| 62 | Computer Networks and Cyber Security | Ethernet & LANs | Baud rate of 10 Mbps Manchester Ethernet | numerical | Medium |
| 63 | Wireless Communications and Networking | Cellular concepts | Methods that prioritise handoffs | conceptual | Medium |
| 64 | Wireless Communications and Networking | Cellular concepts | Measure of users served at a given GOS | conceptual | Medium |
| 65 | Wireless Communications and Networking | Cellular concepts | Techniques that expand cellular capacity | conceptual | Medium |
| 66 | Wireless Communications and Networking | Propagation & path loss | Free-space received power at 10 km | numerical | Medium |
| 67 | Wireless Communications and Networking | Fading & multipath | Received frequency including Doppler shift | numerical | Medium |
| 68 | Wireless Communications and Networking | Fading & multipath | Condition that defines slow fading | conceptual | Medium |
| 69 | Artificial Intelligence | AI foundations | Statement unrelated to AI | conceptual | Easy |
| 70 | Artificial Intelligence | Uninformed search | Frontier data structure for BFS | conceptual | Easy |
| 71 | Artificial Intelligence | Uninformed search | Search with O(bl) space | conceptual | Easy |
| 72 | Artificial Intelligence | Local search | Hill-climbing variant robust to local maxima | conceptual | Easy |
| 73 | Artificial Intelligence | Informed/heuristic search | Search strategy that counts as forward pruning | conceptual | Medium |
| 74 | Artificial Intelligence | Logical inference (chaining) | Knowledge form used by forward chaining | conceptual | Medium |
| 75 | Internet of Things | IoT architectures | Architecture for interoperability of heterogeneous devices | conceptual | Medium |
| 76 | Internet of Things | IoT application protocols | Protocol pair with a tree architecture | conceptual | Hard |
| 77 | Internet of Things | IoT programming frameworks | Framework with broadcast, REST and VM support | conceptual | Hard |
| 78 | Internet of Things | IoT security attacks | Routing attack that lures traffic to a node | conceptual | Medium |
| 79 | Internet of Things | IoT connectivity (802.15.4, LPWAN) | Sigfox operating bands | conceptual | Easy |
| 80 | Internet of Things | IoT protocol stack layers | Stack layer that contains 6LoWPAN | conceptual | Medium |
| 81 | Computer Programming and Data Structures | Programming tools & style | Utility that re-indents program text | conceptual | Medium |
| 82 | Computer Programming and Data Structures | C++ dynamic memory | C++ operator returning address of a new object | conceptual | Easy |
| 83 | Computer Programming and Data Structures | Recursion | Name for recursion removable by looping | conceptual | Easy |
| 84 | Computer Programming and Data Structures | Searching | Search that requires ordered keys | conceptual | Easy |
| 85 | Computer Programming and Data Structures | Sorting | Comparisons needed to verify a list is sorted | conceptual | Easy |
| 86 | Computer Programming and Data Structures | Sorting | Average-case comparison lower bound for sorting | conceptual | Medium |
| 87 | Computer Programming and Data Structures | Sorting | Sorting approach for a thousand index cards | conceptual | Medium |
| 88 | Computer Programming and Data Structures | Sorting | Sort that needs random access to the list | conceptual | Medium |
| 89 | Computer Programming and Data Structures | Hashing | Structure mapping many keys to one slot | conceptual | Easy |
| 90 | Computer Programming and Data Structures | Hashing | Collision method for small records with no overflow risk | conceptual | Medium |
| 91 | Engineering Aptitude | Mensuration | Border width from carpet and cloth costs | numerical | Easy |
| 92 | Engineering Aptitude | Logical puzzles | Birthday date from digit and divisibility clues | numerical | Medium |
| 93 | Engineering Aptitude | Linear equations & averages | Daily interviews by panel A | numerical | Easy |
| 94 | Engineering Aptitude | Data interpretation | Book price from pie-chart costs and profit | diagram-based | Medium |
| 95 | Engineering Aptitude | Ages | Years until an age ratio reaches 7:9 | numerical | Easy |
| 96 | Engineering Aptitude | Simplification | Solve a nested continued fraction | numerical | Medium |
| 97 | Engineering Aptitude | Banker's & true discount | Bill amount from BD minus TD | numerical | Medium |
| 98 | Engineering Aptitude | Ages | Father's present age from family age clues | numerical | Easy |
| 99 | Engineering Aptitude | Arithmetic progression | Sum of 24 AP terms from paired terms | numerical | Medium |
| 100 | Engineering Aptitude | Time, speed & distance | Crossing time of two trains running towards each other | numerical | Medium |
| Q | Topic | Subtopic | What it asks (our summary) | Type | Level |
|---|---|---|---|---|---|
| 1 | Computer Organization and Operating Systems | Memory management (TLB/paging) | Name for fraction of lookups that hit the TLB | conceptual | Easy |
| 2 | Computer Organization and Operating Systems | Storage & RAID | RAID technique that guards against data loss | conceptual | Easy |
| 3 | Computer Organization and Operating Systems | File systems & recovery | File-system design whose logging aids consistency checking | conceptual | Medium |
| 4 | Computer Organization and Operating Systems | CPU scheduling | Pick the sentence describing non-preemptive scheduling | conceptual | Easy |
| 5 | Computer Organization and Operating Systems | OS protection | Protection structure when access needs process number above object number | conceptual | Medium |
| 6 | Computer Networks and Cyber Security | Switching | Identify a drawback of circuit switching | conceptual | Medium |
| 7 | Computer Networks and Cyber Security | Reference models (OSI vs TCP/IP) | Which OSI layers have no TCP/IP counterpart | conceptual | Easy |
| 8 | Computer Networks and Cyber Security | Cryptography | Block-cipher mode that hides repeating plaintext patterns | conceptual | Medium |
| 9 | Computer Networks and Cyber Security | Malware, botnets & attacks | Purpose of the fast-flux DNS technique | conceptual | Medium |
| 10 | Computer Networks and Cyber Security | IDS/IPS & honeypots | Tool for behavioural shellcode detection in IDS/IPS | conceptual | Hard |
| 11 | Computer Networks and Cyber Security | IDS/IPS & honeypots | Honeypot class best for studying post-compromise behaviour | conceptual | Easy |
| 12 | Computer Networks and Cyber Security | Malware, botnets & attacks | Data typically stolen by spyware | conceptual | Easy |
| 13 | Wireless Communications and Networking | WLAN / IEEE 802.11 PHY | Modulation behind 2 Mbit/s 802.11 DSSS | conceptual | Hard |
| 14 | Wireless Communications and Networking | Ad-hoc network routing | On-demand routing protocol paired with DSDV | conceptual | Medium |
| 15 | Wireless Communications and Networking | WAP protocol stack | Optional security layer beneath WAP's session protocol | conceptual | Medium |
| 16 | Computer Networks and Cyber Security | Switching | Layer where virtual-circuit networks are usually implemented | conceptual | Medium |
| 17 | Computer Networks and Cyber Security | IP addressing & subnetting | First and last address of a /16 block | numerical | Easy |
| 18 | Computer Networks and Cyber Security | IP header fields | IPv4 protocol-field value for encapsulated IPv6 | conceptual | Medium |
| 19 | Artificial Intelligence | Decision-making under uncertainty | Framework joining probability and utility theory | conceptual | Easy |
| 20 | Artificial Intelligence | Agents & task environments | Statement that defines a deterministic environment | conceptual | Easy |
| 21 | Artificial Intelligence | Agents & task environments | Agent type that keeps an internal world model | conceptual | Easy |
| 22 | Artificial Intelligence | Uninformed search | What iterative deepening does after a failed depth | conceptual | Easy |
| 23 | Artificial Intelligence | Uninformed search | Time complexity of bidirectional search | conceptual | Easy |
| 24 | Artificial Intelligence | Logical inference (chaining) | Chaining method used in deductive databases | conceptual | Medium |
| 25 | Internet of Things | IoT protocol stack layers | IoT protocol belonging to the physical/device layer | conceptual | Medium |
| 26 | Internet of Things | IoT service discovery | Statement that characterises UPnP in IoT | conceptual | Medium |
| 27 | Internet of Things | IoT programming frameworks | Feature set of the Calvin IoT framework | conceptual | Hard |
| 28 | Internet of Things | IoT application protocols | Match MQTT, XMPP, DDS, AMQP to their roles | match-the-following | Medium |
| 29 | Internet of Things | IoT security attacks | Which description is the transport-layer de-synchronisation attack | statement-based | Medium |
| 30 | Internet of Things | IoT connectivity (802.15.4, LPWAN) | 802.15.4 DSSS data rate and band | conceptual | Medium |
| 31 | Computer Programming and Data Structures | C functions & parameter passing | Statement not true of call by reference in C | conceptual | Easy |
| 32 | Computer Programming and Data Structures | C functions & parameter passing | Rule for passing an array to a C function | conceptual | Medium |
| 33 | Computer Programming and Data Structures | Asymptotic notation | Notation giving a strict upper bound | conceptual | Easy |
| 34 | Computer Programming and Data Structures | Arrays & sparse matrices | Statement not correct about sparse matrices | conceptual | Medium |
| 35 | Computer Programming and Data Structures | Linked lists | Data structure an OS uses for task maintenance | conceptual | Medium |
| 36 | Computer Programming and Data Structures | Queues & priority queues | Structure used to implement Huffman coding | conceptual | Easy |
| 37 | Electronic Devices and Circuits | Semiconductor physics | Formula for free-electron density of a metal | conceptual | Medium |
| 38 | Electronic Devices and Circuits | Semiconductor physics | Fermi level occupancy probability and 0 K filling | statement-based | Easy |
| 39 | Electronic Devices and Circuits | Semiconductor physics | Hole concentration gradient and thermal motion in p-type | statement-based | Medium |
| 40 | Electronic Devices and Circuits | Semiconductor physics | Recombination at surfaces and metal used as recombination agent | statement-based | Hard |
| 41 | Electronic Devices and Circuits | Diode characteristics | Ge vs Si reverse current ratio; current below cut-in | statement-based | Hard |
| 42 | Electronic Devices and Circuits | Diode characteristics | Reverse current versus temperature; dynamic resistance dependence | statement-based | Medium |
| 43 | Digital Electronics | Error detecting/correcting codes | Minimum-distance condition to correct t and detect s errors | conceptual | Medium |
| 44 | Digital Electronics | Counters | Johnson counter modulus; ring counter as divide-by-N | statement-based | Easy |
| 45 | Digital Electronics | Error detecting/correcting codes | Inequality fixing the Hamming parity-bit count | conceptual | Easy |
| 46 | Digital Electronics | Error detecting/correcting codes | Number of Hamming parity bits needed | numerical | Medium |
| 47 | Digital Electronics | Boolean algebra & K-maps | Simplify a product of three sums | numerical | Easy |
| 48 | Digital Electronics | Boolean algebra & K-maps | Minimise a 4-variable function with don't-cares | numerical | Medium |
| 49 | Signals and Systems, DSP | LTI system properties & stability | Property implied by absolutely integrable impulse response | conceptual | Easy |
| 50 | Signals and Systems, DSP | LTI system properties & stability | BIBO stability via ROC and pole locations | statement-based | Medium |
| 51 | Signals and Systems, DSP | Laplace transform | Laplace transform of a normalised power of t | numerical | Easy |
| 52 | Signals and Systems, DSP | Impulse function properties | Sifting integral with impulse outside the limits | numerical | Medium |
| 53 | Signals and Systems, DSP | Impulse function properties | Time-scaling property of the delta function | conceptual | Easy |
| 54 | Signals and Systems, DSP | Impulse function properties | Integral of a delta with negative scaling | numerical | Easy |
| 55 | Analog and Digital Communications | Random processes & probability | Properties of PSD of a stationary process | statement-based | Hard |
| 56 | Analog and Digital Communications | Random processes & probability | Central limit theorem; Gaussian through a linear filter | statement-based | Medium |
| 57 | Analog and Digital Communications | Analog modulation | Definitions of phase and frequency modulation | statement-based | Easy |
| 58 | Analog and Digital Communications | Analog modulation | VSB definition and linearity of DSB-SC | statement-based | Medium |
| 59 | Analog and Digital Communications | Line coding | AMI naming; unipolar vs polar RZ power penalty | statement-based | Medium |
| 60 | Analog and Digital Communications | PCM & sampling | Nature of quantisation noise; PCM fidelity measure | statement-based | Medium |
| 61 | Analog and Digital Communications | Radio wave propagation | Ground-wave band and AM broadcast reach | statement-based | Medium |
| 62 | Analog and Digital Communications | Random processes & probability | Bernoulli variable values, mean and variance | statement-based | Easy |
| 63 | Analog and Digital Communications | Random processes & probability | Chernoff bound origin and applicability | statement-based | Hard |
| 64 | Analog and Digital Communications | Random processes & probability | Definition of a cyclostationary process | statement-based | Medium |
| 65 | Analog and Digital Communications | Digital receivers (matched filter, sync) | Symbol timing: sampling instants and where clock is recovered | statement-based | Medium |
| 66 | Analog and Digital Communications | Channel coding | Recursive convolutional codes and free distance | statement-based | Hard |
| 67 | Microwave Engineering, RADAR Systems | Transmission lines & matching | Single-stub tuning; where shunt stubs suit | statement-based | Medium |
| 68 | Microwave Engineering, RADAR Systems | Microwave resonators | TE01-delta dielectric resonator mode facts | statement-based | Hard |
| 69 | Microwave Engineering, RADAR Systems | Microwave resonators | Loose and critical coupling of resonators | statement-based | Medium |
| 70 | Microwave Engineering, RADAR Systems | Couplers & hybrids | Ideal coupler directivity; hybrid coupling factor | statement-based | Easy |
| 71 | Microwave Engineering, RADAR Systems | Transmission lines & matching | Coupled lines and where TEM is exact | statement-based | Hard |
| 72 | Microwave Engineering, RADAR Systems | Couplers & hybrids | Construction of the Moreno crossed-guide coupler | statement-based | Hard |
| 73 | Satellite Communications | Satellite subsystems (AOCS, propulsion) | Main attitude sensor types and sun-sensor use | statement-based | Hard |
| 74 | Satellite Communications | Satellite subsystems (AOCS, propulsion) | Thrust units and specific impulse relation | statement-based | Medium |
| 75 | Satellite Communications | Earth stations & VSAT | VSAT topology and remote transmit power | statement-based | Medium |
| 76 | Satellite Communications | Radio wave propagation | Meaning of radio propagation; spectrum ordering | statement-based | Easy |
| 77 | Satellite Communications | Antennas & polarization | Co- and cross-polarised horn coupling | statement-based | Easy |
| 78 | Satellite Communications | Earth stations & VSAT | Upconverter role and output frequency | statement-based | Medium |
| 79 | Signals and Systems, DSP | Convolution & deconvolution | Circular convolution of two 4-point sequences | numerical | Medium |
| 80 | Signals and Systems, DSP | Convolution & deconvolution | Linear convolution of two 2-point sequences | numerical | Easy |
| 81 | Signals and Systems, DSP | Convolution & deconvolution | Recover input from output and impulse response | numerical | Medium |
| 82 | Signals and Systems, DSP | DFT properties (circular shift) | Circular shift of a 4-point sequence by two | numerical | Easy |
| 83 | Signals and Systems, DSP | Correlation | Length of a cross-correlation sequence | numerical | Easy |
| 84 | Signals and Systems, DSP | Sampling, anti-aliasing & reconstruction | Alias frequency of a 50 Hz cosine | numerical | Medium |
| 85 | Engineering Aptitude | Direction sense | Relative direction between two cities from clues | numerical | Easy |
| 86 | Engineering Aptitude | Number series | Missing term; second differences rise by 2 | numerical | Easy |
| 87 | Engineering Aptitude | Averages | New class average after adding teacher's age | numerical | Easy |
| 88 | Engineering Aptitude | Ranking & ordering | People between two positions in a row | numerical | Easy |
| 89 | Engineering Aptitude | Coding-decoding & symbol operations | Decode a squares-based rule for a pseudo-division | numerical | Medium |
| 90 | Engineering Aptitude | Coding-decoding & symbol operations | Letter code: mirror letter shifted back two | numerical | Medium |
| 91 | Engineering Aptitude | Direction sense | Straight-line distance after three legs | numerical | Easy |
| 92 | Engineering Aptitude | Direction sense | Net distance and direction after four legs | numerical | Easy |
| 93 | Engineering Aptitude | Ranking & ordering | Middle person in a walking order | numerical | Easy |
| 94 | Engineering Aptitude | Figure/matrix puzzles | Missing letter and number in three grid figures | diagram-based | Medium |
| 95 | Engineering Aptitude | Ages | Present age ratio of mother and son | numerical | Easy |
| 96 | Engineering Aptitude | Blood relations | Relation between two in-laws in a family tree | numerical | Medium |
| 97 | Engineering Aptitude | Calendar | Weekday found from a date offset | numerical | Medium |
| 98 | Engineering Aptitude | Statement & assumption | Implicit assumption behind a no-food notice | conceptual | Easy |
| 99 | Engineering Aptitude | Coding-decoding & symbol operations | Letter analogy with alternating minus/plus five shifts | numerical | Medium |
| 100 | Engineering Aptitude | Odd one out (numbers) | Odd number among four seven-digit numbers | numerical | Hard |
How to use them
Time one paper first
Sit the 2026 paper in two hours with the one-third penalty before reading any analysis. Your raw score against the past unreserved cut-offs (93.33 to 142.00 out of 300) tells you how far you are.
Check against official keys
Only the 2022, 2023 and 2024 papers have official keys. For 2025 and 2026, treat any key, including ours, as unofficial until UPSC publishes its own.
Practise the weak half
Use the topic table above to find the side of the paper you lose marks on, then take the sectional tests for that side before the next full-length mock.
FAQ
UPSC publishes each DCIO/Tech Recruitment Test paper on upsc.gov.in a day or two after the test. The 2026 paper (test of 11 October 2026) was uploaded on 12 October 2026 and the 2025 paper (test of 5 October 2025) on 7 October 2025. This page links the official PDFs for 2022, 2023, 2024, 2025 and 2026.
Yes, but late. UPSC has released the official key for each test only after that cycle's final result: the key for the 2022 test is dated 30 August 2023, the 2023 key 21 November 2024 and the 2024 key 6 October 2025. As of 24 October 2026, the keys for the 2025 and 2026 tests are not published.
100 multiple-choice questions for 300 marks in both the 2025 and 2026 papers: 3 marks for a right answer and one-third of that (1 mark) deducted for a wrong one, in two hours, offline on an OMR sheet, in English only.
In our count of the 2026 paper, electronics and communication topics had 56 questions, computing topics 34 and engineering aptitude 10. In 2025 the split was 51, 33 and 16. Analog and digital communications had 12 questions in both years; electronic devices and circuits rose from 6 to 14; satellite communications fell from 6 to 0.
Yes, once. The 2022, 2023 and 2024 papers had 120 questions of 2.5 marks each; from 2025 the paper has 100 questions of 3 marks. The total (300 marks), the time (two hours) and the one-third penalty for a wrong answer did not change, and all five papers follow the same 13-topic syllabus.
Yes. Reading the papers side by side, we found at least 8 of the 100 questions in the 2026 paper repeated questions from the 2022–2025 papers almost word for word, among them OSI layers missing from TCP/IP, Sigfox bands, SSB-SC power saving and three data-structures questions. Solving every past paper is worth real marks.
Mostly theory. We classed 35 of the 100 questions in 2026 and 27 in 2025 as numerical; the rest test definitions, properties and statements. In 2025, 32 questions were statement-based ("which of the statements is/are correct"); in 2026 there were 0.