Semi conductors(especially transistors).

[HP.builder]

@sophiecentaur
thats all about the flow of electron isn't it, either before it enter the Emitter (CC) or after leaving Collector (CE). BTW, how to intuitively thinking about input / output impedance on both CE and CC configuration.

http://www.photoshop.com/accounts/edd7dd06eb124776b1d8f64eb6b36a8a/px-assets/fe07bff9eaa3449c90bbf3c36024ab73

 

[vk6kro]

I've been trying hard to send you a picture,but the drawing,in 'paint' is too large to send on physicsforums(that's what it keeps saying..my file is 585Kb,whereas the maximum size is 300Kb)...what should I do?

When you save your picture go to "save as" then click the little arrow next to where it says "BMP" and choose "PNG".

Then save your file. It will be a lot smaller than a "BMP" file.

You should be able to attach it after that.

 

[sophiecentaur]

"intuitively thinking" can very easily lead to wrong conclusions unless intuition is based on a very firm base.
I recommend using first principles and calculations until you have more experience and can rely on your intuition.
I think we need a diagram and a link before we can procede.

 

[Urmi Roy]

I did it!...here's the picture...

 

[sophiecentaur]

That diagram doesn't really make sense, does it? I assume that the isolated battery / resistor on the left are actually connected to the base - but that is not the problem. Why not draw the diagram the 'right way up' like the circuit diagrams you can see everywhere else? Are the circles meant to be Voltmeters? The standard is to put a V inside the circles. Are there any ammeters in circuit?
You are wiring the device in a very strange way - the actual values of your resistors are very relevant. You appear to be connecting the base to a positive voltage and the emitter to a negative voltage. In this arrangement it is possible to connect positive supply directly to negative supply via the be junction - owch! - they should never be more than 0.7V. The controls of your parameters are not independent but will affect each other. The bc junction seems to be forward biased (?) or where is 'Earth'?
Don't forget that the transistor was developed to be used in a certain way to act as an amplifier. Is there any point in trying to use it in another way, unless you really have a clue about what's goig on? It's just a good way of getting null results or cooking transistors.
I suggest that you look at websites which can advise you on how to measure transistor characteristics (Google "Measure transistor characteristics", for example) and get all that sorted out before you embark on your own investigation. Random measurements like that are very unlikely to be very fruitful or advance your understanding.
You still haven't given the link to this website you say you have looked at. If you are following what it says then I suggest it may be doing you more harm than good.
This thread is really going nowhere now, is it? I thought, originally, that you really wanted to further your knowledge and understanding of transistors. I have my doubts, now.

 

[Urmi Roy]

I just copied the diagram in my book...what can I do? If that's the way my book puts it,there's nothing I can do about it. Besides,I never said I was referring to any website for information on transistors...I'm already too messed up with my own book.

It's definitely true that I want to get this sorted out...how can you blame me for a diagram that seems wrong to you,but infact that's given in my book?
(by the way,in my diagram,I have grounded the emitter)...my course,as I mentioned before,is not to give me an idea as to what transistors do in practical life,but their very basics only...the diagram might be simplified...but the entire first year in my college is following this diagram only.

 

[sophiecentaur]

Hi
The only path from your emitter to ground is via that potential divider, isn't it? That is not "grounded" in the conventional sense. It is offset from ground by a resistor and the resistor value is highly relevant to how the transistor will look. Unless those circles are voltage sources and not meters. Which are they and, as I asked already, where are you measuring currents?

I quote "I got this idea from a website" Post No. 29

Which book are you getting this from? Is it a textbook or your note book? Any textbook worth having will be much more precise in the notation used in diagrams. Have you copied it accurately? That would be essential as electronic circuit layout is not an 'approximate' subject. I'm not "blaming' you - I'm telling you that the circuit makes very little sense and doesn't seem to relate to any of the results you claim to have obtained (and which you, also, haven't put on view). It's really up to you to decide where any criticism should be aimed. I'm just giving opinions on what you're presenting.
The normal thing to do if one textbook is hard to understand the go to another.
If you got the idea from your teacher then either question her about it or a look for it somewhere else. It just doesn't make sense to me. I could always be wrong but. . . .

Also, I would bet a fair amount of money that youd never ever be asked an exam question on any of this!

 

[Urmi Roy]

Hi
I quote "I got this idea from a website" Post No. 29

I was talking about only the 'descrpition of a circuit' that I found on the site...the author described the circuits in terms of which terminal was grounded to which..so I tried it out that way...perhaps it was naive of me.

I'm not "blaming' you - I'm telling you that the circuit makes very little sense ...

I just thought it was a little unfair of you think that I don't really want to "further my knowledge and understanding of transistors," since that's what I've been trying to do for the last two weeks,even in between my exams,and I will certainly continue to do so.

Anyway,I'll try and look for a better book,of my level.where I could perhaps get a better idea from,as you suggested.

 

[sophiecentaur]

A bit unfair, possibly, but I think that you should really aim in the conventional direction until you are far, far better informed about all the accepted stuff. I have had dealings with a lot of young people (males, mostly) who think that they can get there in their own particular way. I always point out that all the famous names did all the groundwork before thay made their ground breaking discoveries. Ifaik, it's the only way.