R D Supekar book mistakes – a discussion to alert the students

Vidyasagar sir's notes

R D Supekar Book of electronics has number of mistakes…


If you do the preparation using this book, you will lose marks in HSC board examination of Electronics.

Can anyone tell me what is the formula for LOAD REGULATION (LR) of a power supply?

And also what is the criterion for quality of a power supply?
If LR is small then the quality is better or when LR is large then the quality is better…?



This is correct, as given below…

Mistakes in R.D.Supekar's book

THERE IS A MISTAKE IN R D SUPEKAR BOOK ON PAGE NO. 35. All the teachers have been referring this book to check the HSC Board papers of XII Bifocal electronics since last many years.

We have some photo copies of the papers checked by the teachers of Pune Board and Amravati Board who gave full marks to these mistakes, by referring this book.

His book was published with 10+ editions (from April 2000 to Jan 2012 and still more) and still the mistake is same. He never corrected it – at least till this date (22 Dec. 2015)

Now the problem for the students is, if they write the correct formula of LR as given above, then the teachers who are referring the book, will give it as wrong.

And if they write the value of VNL in denominator, then the basic formula would be wrong, but they will get full marks…!

We have found more such serious mistakes in this book. We are collecting the data and soon we shall publish it.

This is the tragedy of our educational system!

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Comments on this entry are closed.

  • Prashik Gawaii (Student)

    December 23, 2015, 7:24 AM

    Why? Is this author not educated?

  • Madhav Dhage (Teacher)

    December 23, 2015, 12:13 AM

    This is really a serious issue particularly. Should be corrected as early as possible.
    Being a teacher I noted it down and will also convey this to my subordinates.
    Hope that the author will take the action as quick as possible.

    • VSAcademy

      December 23, 2015, 10:55 AM

      This was already informed to the author on the Whats App group.
      But he yet didn’t respond.