Request for circuit analysis

Well, I can't really help given what you've asked. So here's some meta- help, on how to ask for help:

First, as you've just found out, this group doesn't allow you to attach binaries. You need to post to flikr or Google Docs or something like that.

Second, you need to ask specific questions. "What about biasing?" is not a specific question. "I am looking at figure XXX on page YYY that is posted here, and I don't understand why R3 is 47k-ohm: I would think it should be 10k-ohm to hold the base at 0.7V".

Then you'll get an answer of the sort "The transistor is in saturation, with a base-emitter voltage controlled by the base-emitter juncion. R3 is there to help the transistor to turn off faster when the voltage is removed from R2".

(Experts will now be able to draw the circuit, confidently giving values and locations for R2 and R1. While most will have R1 and R2 in the same places, no two experts will agree to the values, even though each will say they are best and why. Certain combinations of experts will then spin off a flame war that will carry on for the next two months, so part of your challenge is to ignore that and ask the next question).

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On Sun, 21 Oct 2012 00:35:31 -0500, Tim Wescott wrote: The link for the pages are:

Thanks TM! Regards

are:

you forgot the part about asking a specific question and what specifically you don't understand. No one is going to do you home work for you, you could at least pretend you tried to make an effort

-Lasse

Typed on the pages. Regards

rajibbandopadhyay wrote in news:k607la$9fb$1 @dont-email.me:

That's NOT how it works. You are asking a bunch of complete strangers - many of us highly paid professionals - to give up some of our time to answer your questions. The LEAST you have to do is to ask the questions here so those of us who have no particular interest in the SPECIFIC question can pass over it and to get the attention of those who wish to answer.

Read "How to ask questions the smart way" at:

Then ask your question HERE. We wont do your homework for you but if you make an attempt are likely to help you correct it.

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On Sun, 21 Oct 2012 07:56:14 +0000, Ian Malcolm wrote: I am sorry I could not explain myself better, and wasted your time. The questions are contextual, so are posted on the pages themselves. Regards

I am sorry I could not explain myself better, and wasted your time. The questions are contextual, so are posted on the pages themselves.

I wanted to save your time by posting my questions on the pages themselves. I believe it would definitely save your time. Regards

Mate, just post the questions one at a time. Then there will be no confusion and you can consider the answers before posting the next.

Cheers ....... R.P

There are no friggin pages here.

On Sun, 21 Oct 2012 05:09:23 +0000, rajibbandopadhyay wrote: The problems in detail: The pages are in:

Page 249 has a circuit diagram. Problem 9 is given near end of page and continues in Page 250. The Problem 10 refers to the same circuit and defines voltage gain by a formula. How this formula is derived? Instability and solution is given in Page 253, Problem 11 and a circuit diagram is given. Then formula for gain is given. But how this formula is derived? Page 256 has a problem 17 continued in page 257. Steps are given. But if the gain part can not be derived then the solution can not be arrived at, which are continued in page 258.

The url you posted does not display large enough in either IE or Firefox 16.0.1. What is visible does not show a diagram on page 249.

To get answers, you will need to find a better way to ask your questions. I'll try to give you a method: "ASCII art"

Here is what I can make out on page 248 in "ASCII art" (Not shown is the sine wave input and inverted sine wave output)

+-------------------+ | | [R] [R] | | | +---Vc | | | / ---[C]---+-----------------| > | -----------------------------+

You can use the above diagram (if it is the one you have in mind) to ask your question.

Or you can find another way. We can't help if we can't see.

Ed

[snip overly generalized questions]

The images are too small to read. And using the zoom in IE9 actually makes the image smaller.

From what I can see, you have no idea how to apply Ohms Law, and you don't understand basic transistor characteristics such as Vbe diode junction and current gain. You may need to go back a few (hundred) pages and comprehend the basic principles of circuit components.

Have you ever actually built a simple circuit?

Have you tried using a simulator like LTSpice?

(a tutorial to get started)

Paul

+1

Two hints concerning ASCII art and circuit diagrams: You *MUST* use a fixed pitch font to view ASCII art or the lines dont match up vertically. If you don't know which font to use, try "Courier New".

There's a utility for Windows called AAcircuit that helps you draw ASCII art circuit diagrams. Simply use it to edit your diagram till you are happy with it, then use its menu option to copy to clipboard, then paste into your next newsgroup posting. The program is German but you can also select English or Danish.

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Ian Malcolm.   London, ENGLAND.  (NEWSGROUP REPLY ONLY)

Question: are you, Rajibb and Padhyay close brothers - like the famous Science Fiction writer Eando Binder?

On Mon, 22 Oct 2012 22:12:46 -0800, Robert Baer wrote: [...]

Query replied to privately.

Around 1970 I wrote a tutorial on biasing for ICE, but haven't been able to locate a copy. The following example MAY be of help to you...

while I look around for the write-up of more generalized methods. ...Jim Thompson

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You're not going to learn much from a book like that, it is just recipes. The gain equation for the uncompensated config beta x Rc/ hie is more symbolic than numerical since hie is all over the map depending on collector current swing.

[...]

And I would be eagerly waiting... Regards