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The information should be in the post, not the title, why do people do this, very enoying. Give us the name of the transistor.Question is in the title, please answer.
We really do need our own tutorials. This is the second time this week that we had to post a link (OpAmp) to AC. It really sucks having to send new members there.It can be a rather long process to explain so check here....
http://www.allaboutcircuits.com/textbook/semiconductors/chpt-4/meter-check-transistor-bjt/
I have to take issue with this method, especially as it depends on the sensitivity of a meter.It can be a rather long process to explain so check here....
http://www.allaboutcircuits.com/textbook/semiconductors/chpt-4/meter-check-transistor-bjt/
Uncle Chris,nubes are fortunate that they were born in a era that Geraniums are just history.
Thanks Steve, I should have said as far as operation of the transistor is concerned.Not any limitations of the device.well... The reverse breakdown voltage of the base emitter junction I'd far lower than the base collector junction, so it will care if there is more than about 8v across it.
A transistor will exhibit some gain with the emitter and collector reversed, but far less. This is probably the best way to distinguish them.
For devices with a heat sink or metal case, if this is connected to anything, it week be the collector. In fact, TO-3 devices only have 2 leads. You connect to the body of the device as the collector connection.
Thanks Steve, I should have said as far as operation of the transistor is concerned.Not any limitations of the device.
Adam
I have to take issue with this method, especially as it depends on the sensitivity of a meter.
Just to clarify, I have four meters. Three digital and one analog. And never ONCE have I successfully been able to identify Emitter or Collector.
There is obviously the possibility that I am just plain dumb! But it does seem to depend on the pressure applied to the probes and how sharp they are too.. (readings CAN differ minutely)..
So I certainly wouldn't trust that method as a beginner...
Martin
Uncle Chris,
I had a situation last month where I threw away a bunch of LEDs, thinking they were dead. It never crossed my mind to reverse the polarity.
I had this same thought Chris, a universal transistor tester. Each leg would have three LEDs located near to the leg, each one labelled BCE and then which ever light lights indicates that terminal is either base, collector or emitter. Martin, I just found your next projectThink about what a fun uC project this would make. Imagine it cycling through the pinouts using safe current and voltage limiting. Then outputting the data to an LCD along with serial interface to a PC to create a log file.
Chris