Before Interview
I reached Mumbai on 2 June one day before my interview slot
day. My interview was on 3rd june 11 am slot. i reached barc centre at 10:30.
after registering and completing all formalities , i was allotted 22 no.
slot NBH hostel 11 floor.I meet my
friend satish there, and wait in waiting room for my no. 22, I asked interview
question from already interviewed candidates and try to solve all the
questions. it was very helpful for me to understand level of difficulties and
logic behind questions. we had a lunch on 1 pm. then we were waiting again.
Then i asked volunteers for my interview slot time. they told me that i was
last candidate of my panel. then i relaxed and phoned to my friends to help to
solve some difficult questions. it was around 5:30, I searched for some water
and left waiting room. suddenly volunteers called my name, then i was nervous
and entered the interview room.
My journey to 1hour 40 minutes starts...
There was a round table in which 6 person in the room
including chairman and a lady maam. panel chairman told me for introduction
slip(green slip). Due to nervousness, i told then i was not given any slip.
they again told me for the same. I thought for the slip, i found that i left my
slip outside the interview room. I said sorry to them, and left room to bring
slip and entered the room again. I was so horrible for me. I had mistake in
such a important interview. they offered me some water and said to be relaxed
himanshu. I said sir it was my first interview, so i was nervous. They asked me
about college, father etc.
finally my interview started, they told me to write my five
prepared subjects in a A4 paper. They gave you pencil and paper to write it. I
wrote it in order 1. electronics devices(EDC), 2. analog electronics, 3.control
system, 4. Electromagnetic field theory, 5. signal and system.
1. EDC questions...
They asked me to tell about yours subjects content. i
started with EDC and said diode, BJT, mosfets, special diodes eg. tunnel,
varactor, imapatt. they said anything other. then i said optoelectronics
devices like led, photo diode, LASER. on listening laser, they asked first
question define laser. fortunately, i had a interview at DRDO for LASER
technology jrf post earlier. I told them sir i was a Hindi medium student so i
was comfotable in Hindi. they said yes you can proceed in Hindi. I started with
laser from its basics, fermi diagram, population inversion, threshold current,
intensity vs. current plot, difference b/w led and laser etc. then they told
about some practical questions, i told them sir i did not know sir but i can
try it. they permitted. then i tried to answer some difficult question of laser
like laser beam modulation circuit, and
i was able to give reasonable answers not 100% correct but interviewer
needs. my logics was correct, i told them sir i had read streetman and banerjee
for semiconductor physics, and it contain only those things which i had already
said. they impressed and asked some typical question of that book. i answered
that. they asked some question related optical fibre application of LASER, i
tried to give basic answer. but they need detailed answer. i told sir it was
part of opticle fibre not EDC, i was prepared for EDC only but i can read
optical fibre. then questions from laser come to end.
2. Alalog
they asked first question from multi vibrator. design
astable using op amp. I designed circuit
quickly. they told me explain every bit of it while drawing ckt. i said ok sir.
i explained completely. they asked me to draw a ckt in which duty cycle of
generated square wave can be changed in astable mode. it was new question for
me, i have never solved it. i told them sir i would try. i thought and finally
success to draw it by modifying with two diodes and resistors. then they asked
about oscillators, i defined basics of oscillators, positive feedback, etc.
they asked me to draw any ckt. I draw ckt of phase shift oscillator using op
amp and explained it thoroughly. but wrote wrong equation of its oscillation
frequency, i was forgotten it. they avoided my mistake.
3. Control System
they asked first question very easy like rise time, settling
time, peak time etc. I explained that. but madam(interviewer) was from bengal
so she dont know hindi. she told me to explain in english they i explained in
english those question for her. she asked me about controllers. i answered.
then she give me a block diagram representation of a control system and asked
about it. It was piece of cake for me because i have leaned that in my third
year training at NTPC Rihand. I said maam it was drum level controller. she
said how did you know it. i told her about my training. she said ok and asked
all parameters of drum level controller eg. instruments used, its purpose,
logic behind its working,actuators, feedback(sensor) etc. then she asked how to
control it when water is flowing
continuously. i answered by using proportional controller. then she asked when
its level swelling(oscillating) then how to control it. i know its logic but
due to over confidence i give wrong answer PD controller but afterward i
corrected my mistake and told her maam its PI controller. i said sorry, maam i
was actually know answer but unfortunately my mind and mouth did not
synchronize it. they said himanshu no problem.
4. Electromagnetic field theory(EMT)
It was toughest part of my interview. A person from my panel
give me a circuit and give its parameters and asked to solve it. This question
was from transient analysis of transmission lines, which was not in syllabus of
my university. it was not in saidiku (standard book of EMT). i have never heard
it before GATE exam. i found one question of it in 3rd set paper of gate. when
i planned preparing for BARC interview then i downloaded a ebook
Electromagnetic field theory by Markus Zahn. It contain this topic, but i had
not sufficient time to read it thoroughly. i read little bit about it. I solved
ckt. by using some equation but it was not the answer of my problem. they give
some hints. i told them sir i cant use any equation of transmission lines
directly on it, because all the equations derived for steady state analysis.
they said yes but how to solve it. i use my brain but unable to solve it. they
changed this question and make it more difficult, they asked me about a power
station generates 130kv, 100 amp current, send to same transmission line if
lightening fall on transmission line then about its impudence behavior. i
smiled and thought it was a question of electrical power system then why they
asked such question to a electronics candidate. I told some answer, they asked
about logic. it define logic of lightening. My logic was little bit correct but
perhaps answer was not. they did not responded, and go to next subject.
5. signal and system
when i was answering EMT question, they interrupted me and
give a circuit to find voltage waveform at three different nodes. It was
actually problem of Network not signal and system. It was a circuit of three
loops containing resistor, capacitor and inductor and parameters values were
not given. they told me solve it by using minimum solution, using logic only
and draw approximate waveform of voltage. i was horrified to see circuit, how
to solve it without solving it actually. i told them sir give me parameters
value. they said not needed. then i thought some time, use my brain and finally
able to draw one waveform. I saw faces of all person and told sir is it
correct? they said draw second and third. I managed to draw second waveform by
analyzing the ckt. but it was wrong. they interrupted me and said think again
himanshu. i took some more time and draw the correct waveform. i asked them,
they said draw third. third was very easy for me. i draw third one quickly.
they told me some more question about it. I solved that questions.
Final questions
In the end, they asked me about digital system. i told them
sir i had not prepared for it for BARC but i know basics of digital, i can try.
they asked me about TTL level. I answered ttl voltage 0 and 5V. they said no. i
said sir ideally we call 0 and 5v but practically some voltage range. they
asked what range? I have forgotten it, so give wrong range. then other person
asked me define noise margin. I was explaining it. meanwhile chairman
interrupted all person. chairman said himanshu, you are ready for project work.
i said yes. he told me you might be posted in rural area, would you be
comfortable. I said yes sir."i had already done my vocational training in
NTPC Rihand, which is also a rural and backward area but i completed my
training there in fact I wanted to stay there some more days. I am also belong
to small town mirzapur. sir i would have no problem." I already make my
mind make up to work for power sector.He asked me about college placement. I
told him that i was not placed in college due to lack of communication skills.
sir you could see I gave my interview in Hindi. some peoples in the panel
suggested me to improve spoken English not by reading book but to speak. I said
yes sir, i totally focused my mind on technicals for BARC, afterward i would improve
my spoken english.
Then they say thanx, and chairman said now you can go. I
also said thanx to all of them and my interview end.i checked my interview time
which was appox 1 hour 40 minutes.i saw there were no person outside the room.
it mean all the candidates had already interviewed. i was very happy and
waiting for final result. finally on 24 june my hard work, blessings and dream
became true. I was selected as Scientific Officer at Bhabha Atomic and Research
centre.
