---
title: "Drawbacks of manual telephone exchanges"
subject: "Telecommunications"
chapter: 1
key: "semester_8/telecommunications:manual-exchange-drawbacks"
source: https://www.bctengineer.com/q/semester_8/telecommunications/manual-exchange-drawbacks
site: BCT Engineering
---

# Drawbacks of manual telephone exchanges

Telecommunications · Chapter 1: Telecommunication Networks

- Asked in: 2076 Asoj, 2 marks
- Video: [Manual EXCHANGE - Telephone Exchange](https://www.youtube.com/watch?v=lP5HCNBAxLI) — TTC Daharki Online Academy 
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_8/telecommunications/manual-exchange-drawbacks
- Whole chapter: https://www.bctengineer.com/md/semester_8/telecommunications/chapter-1

## Question

List the major drawbacks of manual telephone exchanges.

## Short answer

Manual exchanges have slow call set-up, poor privacy because operators hear calls, human errors, high operator running cost, limited capacity, dependence on operator mood and no advanced services.

## Answer

Major drawbacks of manual telephone exchanges:
- **Slow call set-up:** operator must answer, ask the number and plug cords.
- **Lack of privacy:** the operator can hear and know who is calling whom.
- **Human errors:** wrong connections, delays, language and accent problems.
- **High running cost:** many operators needed round the clock.
- **Limited capacity:** a switchboard can handle only a few hundred lines; large cities need many boards.
- **Operator dependence:** service quality varies with operator mood and fatigue; possible favouritism.
- **No advanced services** and poor 24-hour service in small exchanges.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Why is privacy a problem in manual exchanges?
   A. Cords are visible to subscribers
   B. The operator can hear and know who calls whom
   C. Subscribers share the same line
   D. Pulses leak to others
   Answer: B. The operator is in the call path. (Key point: Privacy)

2. Capacity limit of a manual switchboard is
   A. Tens of thousands of lines
   B. Unlimited
   C. Only a few hundred lines
   D. Exactly 10 lines
   Answer: C. Large cities need many boards. (Key point: Capacity)

3. Why is running cost high?
   A. Cords wear out in a week
   B. Power use is huge
   C. Subscribers are charged nothing
   D. Many operators are needed round the clock
   Answer: D. Operators are needed 24 hours. (Key point: Cost)

## Related in Telecommunications

- [Major types of telephone exchanges](https://www.bctengineer.com/question.md?key=semester_8%2Ftelecommunications%3Atelephone-exchange-major-types) — Telecommunications, chapter 1