UJT is used to generate:

This question was previously asked in
RRB ALP Electronics Mechanic 23 Jan 2019 Official Paper (Shift 2)
View all RRB ALP Papers >
  1. sine wave
  2. square wave
  3. triangle wave
  4. sawtooth wave

Answer (Detailed Solution Below)

Option 4 : sawtooth wave
Free
General Science for All Railway Exams Mock Test
2.1 Lakh Users
20 Questions 20 Marks 15 Mins

Detailed Solution

Download Solution PDF

The correct answer is option 4.

Unijunction Transistor (UJT)

F1 Engineering Savita 5-4-23 D5

The Unijunction Transistor is a solid-state three-terminal device that can be used in gate pulse, timing circuits, and trigger generator applications to switch and control either thyristors or triacs for AC power control type applications.

A UJT consists of a single solid piece of N-type semiconductor material forming the main current-carrying channel with its two outer connections marked as Base 2 (B2) and Base 1 (B1). The third connection, confusingly marked as the Emitter (E) is located along the channel. The emitter terminal is represented by an arrow pointing from the P-type emitter to the N-type base.

UJT uses the negative oscillator resistance property for the generation of the sawtooth waveform.

UJT is a device that possesses negative resistance characteristics which means its emitter current rises regeneratively when triggered. Thus an emitter supply is needed in order to restrict it. In normal operating conditions, it generally absorbs less power and hence is an efficient device.

The characteristic of UJT is given below:

qImage9238

Latest RRB ALP Updates

Last updated on Jun 2, 2025

-> The RRB NTPC Admit Card 2025 has been released on 1st June 2025 on the official website.

-> Railway Recruitment Board activated the RRB ALP application form 2025 correction link, candidates can make the correction in the application form till 31st May 2025. 

-> The Railway Recruitment Board (RRB) has released the official RRB ALP Notification 2025 to fill 9,970 Assistant Loco Pilot posts.

-> The Railway Recruitment Board (RRB) has released the official RRB ALP Notification 2025 to fill 9,970 Assistant Loco Pilot posts.

-> The official RRB ALP Recruitment 2025 provides an overview of the vacancy, exam date, selection process, eligibility criteria and many more.

->The candidates must have passed 10th with ITI or Diploma to be eligible for this post. 

->The RRB Assistant Loco Pilot selection process comprises CBT I, CBT II, Computer Based Aptitude Test (CBAT), Document Verification, and Medical Examination.

-> This year, lakhs of aspiring candidates will take part in the recruitment process for this opportunity in Indian Railways. 

-> Serious aspirants should prepare for the exam with RRB ALP Previous Year Papers.

-> Attempt RRB ALP GK & Reasoning Free Mock Tests and RRB ALP Current Affairs Free Mock Tests here

Get Free Access Now
Hot Links: teen patti fun teen patti 3a teen patti star apk teen patti master update teen patti party