Electronic Projects, forums and more.

Go Back   Electronic Circuits Projects Diagrams Free > Electronics Forums > Electronic Projects Design/Ideas/Reviews


Electronic Projects Design/Ideas/Reviews Are you building an electronic project or want to? Maybe you need some assistance? Come and submit your electronic questions here and let our experienced members find a solution.

Reply
 
LinkBack Thread Tools Display Modes
Old 4th March 2004, 07:58 AM   (permalink)
Default transistor help

ey guys. .. just a simple question.. :shock: . how would you determine or recognize if it is the emitter and the collector in a transistor by using the multitester manually..
:lol: :lol:
ellsworth is offline  
Old 4th March 2004, 08:21 AM   (permalink)
Default

The emitter-base junction breaks down at a much lower voltage than the collector-base junction. Some multimeters apply 9V at the terminals at the high resistance range. They will read a lower resistance when you connect the terminals to the base & emitter vs. base & collector.
__________________
"Having to do with Motion Control"
motion is offline  
Old 4th March 2004, 01:02 PM   (permalink)
Default

If u set a multimeter to the resistance measurement setting, there is a voltage available on the terminals, oppsoite in polarity to the terminals. Clip the terminals to the emitter and collector in any way. Now when u earth the base by a metal object say a forcep or a screwdriver or by ur hand, the resitance between the emitter and collector terminals will drop significantly if the terminals are applying voltage to the emitter and collector in the proper sense i.e. for the npn transistor emitter is connected to negative i.e. the red terminal and collector to the positive or the black terminal. The reverse is the case for pnp transistor. If the terminals are not connected like this the resistance drop will be almost insignificant.
It works for many transistors.
aryajur is offline  
Reply

Bookmarks

Thread Tools
Display Modes





All times are GMT. The time now is 01:17 AM.


Electronic Circuits  |  Learning Electronics
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.

eXTReMe Tracker