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Job interview help! Good analog primer?

  • Thread starter Lewin A.R.W. Edwards
  • Start date
L

Lewin A.R.W. Edwards

Jan 1, 1970
0
Hi all,

I'm going to a second-round job interview next Monday, and I've been
forewarned by the first-round interviewer that I will be asked
questions on analog and RF topics (basic op-amp circuits, transistors
used in switching and amplification apps, superhet receivers and AM
transmitter).

I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF are not
my strong point - and I made this clear to them before ever coming in)
but I would like to have as good a briefing as possible. He
recommended the ARRL Radio Comms handbook, which is totally
unavailable near me (libraries, bookstores, etc). I ordered a copy
from amazon, but I'm worried that it won't arrive in time.

So, can anyone suggest other references that are either available
online, or likely to be in Barnes and Noble? I'm looking for
introductory overview type information rather than detailed
down-to-the-last-electron info.

AAMOI: the interview technique he used was, among other things, to
give me a large mixed-signal schematic and a stuffed board, and leave
me to look at it for 15 minutes, then I had to describe as far as
possible the function of the various blocks in the circuit. I did
tolerably well on that. But the second part of the test was 15 minutes
with a snippet (~10 pages) of assembly source for a micro I'd never
used. THAT was fun. Didn't do at all well on that. Oh well. I hope the
aim was to observe behavior under stress :)

Any assistance will be karmically rewarded :)))
 
J

John Larkin

Jan 1, 1970
0
Hi all,

I'm going to a second-round job interview next Monday, and I've been
forewarned by the first-round interviewer that I will be asked
questions on analog and RF topics (basic op-amp circuits, transistors
used in switching and amplification apps, superhet receivers and AM
transmitter).

I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF are not
my strong point - and I made this clear to them before ever coming in)
but I would like to have as good a briefing as possible. He
recommended the ARRL Radio Comms handbook, which is totally
unavailable near me (libraries, bookstores, etc). I ordered a copy
from amazon, but I'm worried that it won't arrive in time.

So, can anyone suggest other references that are either available
online, or likely to be in Barnes and Noble? I'm looking for
introductory overview type information rather than detailed
down-to-the-last-electron info.

AAMOI: the interview technique he used was, among other things, to
give me a large mixed-signal schematic and a stuffed board, and leave
me to look at it for 15 minutes, then I had to describe as far as
possible the function of the various blocks in the circuit. I did
tolerably well on that. But the second part of the test was 15 minutes
with a snippet (~10 pages) of assembly source for a micro I'd never
used. THAT was fun. Didn't do at all well on that. Oh well. I hope the
aim was to observe behavior under stress :)

Any assistance will be karmically rewarded :)))

Win Hill's book, The Art of Electronics, would be a good cram course.
It's available everywhere.

John
 
J

Joe Legris

Jan 1, 1970
0
Lewin said:
Hi all,

I'm going to a second-round job interview next Monday, and I've been
forewarned by the first-round interviewer that I will be asked
questions on analog and RF topics (basic op-amp circuits, transistors
used in switching and amplification apps, superhet receivers and AM
transmitter).

I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF are not
my strong point - and I made this clear to them before ever coming in)
but I would like to have as good a briefing as possible. He
recommended the ARRL Radio Comms handbook, which is totally
unavailable near me (libraries, bookstores, etc). I ordered a copy
from amazon, but I'm worried that it won't arrive in time.

So, can anyone suggest other references that are either available
online, or likely to be in Barnes and Noble? I'm looking for
introductory overview type information rather than detailed
down-to-the-last-electron info.

AAMOI: the interview technique he used was, among other things, to
give me a large mixed-signal schematic and a stuffed board, and leave
me to look at it for 15 minutes, then I had to describe as far as
possible the function of the various blocks in the circuit. I did
tolerably well on that. But the second part of the test was 15 minutes
with a snippet (~10 pages) of assembly source for a micro I'd never
used. THAT was fun. Didn't do at all well on that. Oh well. I hope the
aim was to observe behavior under stress :)

Any assistance will be karmically rewarded :)))

How about applying for a job for which you are actually qualified? If
you cannot answer these questions without cramming even your digital
"skills" are bogus. I seem to recall your last job at Digi-Frame (?) and
your heart-rending series of accounts of their financial difficulties
and your resulting "ethical" dilemmas. Where are your ethics now?
 
C

CBFalconer

Jan 1, 1970
0
Lewin A.R.W. Edwards said:
I'm going to a second-round job interview next Monday, and I've
been forewarned by the first-round interviewer that I will be
asked questions on analog and RF topics (basic op-amp circuits,
transistors used in switching and amplification apps, superhet
receivers and AM transmitter).

I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF
are not my strong point - and I made this clear to them before
ever coming in) but I would like to have as good a briefing as
possible. He recommended the ARRL Radio Comms handbook, which
is totally unavailable near me (libraries, bookstores, etc). I
ordered a copy from amazon, but I'm worried that it won't
arrive in time.

I have my doubts that it will be too helpful. That is full of
cookbook formula, and very little basic theory, which makes it a
useful reference. At least it used to be so.

You might do well snooping around university stores and looking
for books used in some of the introductory courses. Similarly any
technical schools in your area.

Taking your subjects in order, to my mind the critical facets are:

op-amps: Feedback.

transistors: leakage currents, breakdown voltages, beta.

superhet: sum/difference frequency to get constant frequency IF.
There are systems with tunable IFs also (IF = intermediate
frequency). Image frequency rejection.

AM transmitter: Output amplifier classes (A, B, C) and
modulation. Class C and modulation don't mix very well.

Sounds like a place that would value all my ancient obsolete
knowledge.
 
B

Bob F.

Jan 1, 1970
0
What about electromagnetic theory, antennas, transformers, microwaves. Do
you need to know any of this? Good luck cramming it all in this weekend!

To further hasten your generation's tendencies to cheat rather that take the
time to actually LEARN a subject, let me offer you the following
second-round technical interview tips:

It sounds to me like they'll be doing something like showing you simple
operational amplifier circuits and asking you to decide if its an
integrator, a differentiator, a voltage follower, an inverting amplifier.
Learn what these op-amp configurations and their gain equations look like.
For example, the gain equation of an inverting amplifier is A = -RF/RI
(Just to clue you in here, 'A' is the symbol for Gain, 'RF' symbolizes the
feedback resistance, 'RI' symbolizes the input resistance).

If they are testing you on transistors, they'll probably ask you "Is this a
P-N-P, or an N-P-N?" "Is this a push-pull amplifier" You might actually
try memorizing the transistor symbols so that you can differentiate a
bipolar transistor from a FET.

Can you spot the difference between a low-pass filter and a high-pass
filter? Didn't think so, why don't you look that one up too!

Can you spot the difference between a capacitvely-coupled circuit and a
transformer-coupled circuit? Do you even know what capacitors and
transformers are?

During your interview, be don't miss the flux-capacitor, its a common
component usually attached between Vcc and Gnd.

Good luck and let us know how you do!
 
D

Dbowey

Jan 1, 1970
0
cbfalconer posted, among other things:

<< AM transmitter: Output amplifier classes (A, B, C) and modulation. Class C
and modulation don't mix very well. >>

Actually, class C and modulation mix very well. For high-level (plate)
modulation, the class C RF amplifier provides the non-linear function required
for modulation of the RF signal.

Don
 
R

Rob Turk

Jan 1, 1970
0
Lewin A.R.W. Edwards said:
AAMOI: the interview technique he used was, among other things, to
give me a large mixed-signal schematic and a stuffed board, and leave
me to look at it for 15 minutes, then I had to describe as far as
possible the function of the various blocks in the circuit. I did
tolerably well on that. But the second part of the test was 15 minutes
with a snippet (~10 pages) of assembly source for a micro I'd never
used. THAT was fun. Didn't do at all well on that. Oh well. I hope the
aim was to observe behavior under stress :)

If you want ARRL books, find a Ham Radio Outlet shop (www.hamradio.com) near
you. They usually have the entire ARRL line of documentation readily
available. If you're outside the USA, call your local ham radio group and
ask where to get those books.

But as the other posters already suggested, I can only wish you luck in
reading that much info, let alone understand it. Would you be able to tell a
Colpitts oscillator from a Hartley after reading the basics on transistors
or opamps? I doubt it. Best is to be fit for the interview and keep an open
mind. That might work better than being dead-on-arrival from studying all
weekend...

Rob
 
D

Dbowey

Jan 1, 1970
0
Joe Legris posted to Lewin:

<< How about applying for a job for which you are actually qualified? If you
cannot answer these questions without cramming even your digital "skills" are
bogus. I seem to recall your last job at Digi-Frame (?) and your heart-rending
series of accounts of their financial difficulties and your resulting "ethical"
dilemmas. Where are your ethics now? >>

Well, Joe, where are your ethics?

Do you really just "seem to recall," or do you in fact recall? One should not
run off at the mouth about things of which they are not certain.

I'm certain you are a jerk.
 
A

Al Cohen

Jan 1, 1970
0
Ouch. Analog is very non-trivial.

First, I'd second the recommendation of another poster by suggesting
Horowitz & Hill's "The Art of Electronics" as a good all-around reference.

Don Lancaster is an amazing resource, www.tinaja.com.

If I were looking for a firmware person, the most I could reasonably
expect them to understand would be op-amp circuits. In general, at
least in the real world, most analog circuits are built of little blocks
that usually revolve around an op-amp with some feedback from output to
input. Common building blocks include:

- inverting amplifiers
- non-inverting amplifiers
- filters (a big topic - lots of variations here)
- comparators (sort of like op-amps with no feedback)
- integrators
- instrumentation amplifiers

A little on transistors. Transistors are usually brought in to boost
current-handling capabilities when op-amps can't cut it, although there
are many other uses for transistors as well.

There's about a billion other things that one can know about analog
circuits; but it takes years and years of frying things to learn most of it.

Good luck!

Al Cohen
www.alcohen.com
 
L

Lewin A.R.W. Edwards

Jan 1, 1970
0
How about applying for a job for which you are actually qualified? If

Charming. Yes, I also eat small kittens for breakfast, rob the
elderly, kick puppies, and routinely throw kindergarteners in front of
buses.

I would not bother applying, let alone going to a first-round
interview, for a job that I couldn't do. What on earth would be the
point? They would know within ten minutes that I didn't have a clue. I
described my analog knowledge as rudimentary and RF as practically nil
up-front, before even coming in for an interview. I simply haven't
needed such knowledge in the jobs I've worked, and my education has
been project-driven for most of my working life.

As I understand it, the context of this info is primarily being able
to understand what the analog peripherals are doing without being too
much of a load asking questions of the design team. The duties in the
job description do NOT include RF or analog design.

It has also been stated to me that if I'm offered the position, it
will basically be conditional on my going back to school. Implication
from that being that they understand I'm not a perfect match for every
bullet point on their list, but they are willing to work with that.
Also, as you doubtless well know, most job descriptions read "The
ideal candidate will have 25 years' experience in designing spacecraft
and nuclear submarines, at least one platinum solo R&B album, a
distinguished military service record, a personal letter of
congratulation from the Pope, and will be a former champion sumo
wrestler and/or ballerina." Few hiring managers succeed in matching
all bullet points on their wishlist.

So, kindly don't make such accusatory statements without a solid basis
of fact. People who matter read public forums like this. I believe I
have a reasonably consistent and solid sense of ethics, and I KNOW I
have an excellent comprehension of my own limitations, and I don't
much care for people who jump to unwarranted conclusions and then
slander me in public.

Oh yes - As I recall, I also posted the previous thread to which you
refer anonymously, so that it could not directly be associated with me
(e.g. by potential acquirers of my current employer, who would
perceive significantly diminished value in the company if I were to
leave it). Some people - and you may have been one of them -
successfully reverse-engineered my identity from my writing style,
which is something I could not avoid. The ethical thing for you to do
in such a case is to respect my desire to keep the original thread
anonymous.
 
A

Al Borowski

Jan 1, 1970
0
There's no reason to be condensending. And stereotyping an entire
generation as 'cheaters' is just arrogant.

Al
 
L

Lewin A.R.W. Edwards

Jan 1, 1970
0
(numerous pieces of humor). See my response to Legris, but I'm not as
irritated at you as I am at him.

When I say my analog knowledge is rudimentary, I don't mean I can't
identify a transistor or use one in a simple switching or
uncomplicated amplifier application, or use a Darlington pair to drive
a motor, or put in a snubber diode to mitigate inductive kickback. I
mean, for example, that I can't just glance at an op-amp configuration
and know immediately what it is; I need to think about it and even
then I don't always get it right. It's been a long time since I read
about these things, and it's not information I've often had to think
about or use, hence my lack of facility with it.

As for RF, well, I don't do it.

I'm not interested in acquiring several years' knowledge in a weekend;
even if I wanted to try it, I am positive that any such attempt would
be detected instantly by the people I'm talking to. I'm looking for a
reference that will remind me of where the larger holes are in my
knowledge, and will stretch some temporary walkways over the smaller
holes.

I'm not even sure it is worth my while spending the weekend on this
rather than doing some of the actual work I have queued up, but I
figure I should give it extra effort because the job sounds
interesting. The world will not end if I don't get an offer.

I think I gave too much contextual information in the question. I
could simply have said "I was recommended this book as containing XYZ,
what other book covers similar ground?" My mistake, won't happen
again.
 
L

Lewin A.R.W. Edwards

Jan 1, 1970
0
(numerous pieces of humor). See my response to Legris, but I'm not as
irritated at you as I am at him.

When I say my analog knowledge is rudimentary, I don't mean I can't
identify a transistor or use one in a simple switching or
uncomplicated amplifier application, or use a Darlington pair to drive
a motor, or put in a snubber diode to mitigate inductive kickback. I
mean, for example, that I can't just glance at an op-amp configuration
and know immediately what it is; I need to think about it and even
then I don't always get it right. It's been a long time since I read
about these things, and it's not information I've often had to think
about or use, hence my lack of facility with it.

As for RF, well, I don't do it.

I'm not interested in acquiring several years' knowledge in a weekend;
even if I wanted to try it, I am positive that any such attempt would
be detected instantly by the people I'm talking to. I'm looking for a
reference that will remind me of where the larger holes are in my
knowledge, and will stretch some temporary walkways over the smaller
holes.

I'm not even sure it is worth my while spending the weekend on this
rather than doing some of the actual work I have queued up, but I
figure I should give it extra effort because the job sounds
interesting. The world will not end if I don't get an offer.

I think I gave too much contextual information in the question. I
could simply have said "I was recommended this book as containing XYZ,
what other book covers similar ground?" My mistake, won't happen
again.
 
T

Tim Auton

Jan 1, 1970
0
CBFalconer said:
Lewin A.R.W. Edwards said:
I'm going to a second-round job interview next Monday, and I've
been forewarned by the first-round interviewer that I will be
asked questions on analog and RF topics (basic op-amp circuits,
transistors used in switching and amplification apps, superhet
receivers and AM transmitter).
[snip]
You might do well snooping around university stores and looking
for books used in some of the introductory courses. Similarly any
technical schools in your area.

Why not the local university library? Over here (the UK) most are
happy for you to wander in and use the resources if you say hello and
stick to the rules. You can even borrow books for a moderate fee;
borrowing from my local university library costs about £25 ($40) per
year for non-students/staff.


Tim
 
P

Paul Keinanen

Jan 1, 1970
0
I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF are not
my strong point - and I made this clear to them before ever coming in)
but I would like to have as good a briefing as possible. He
recommended the ARRL Radio Comms handbook, which is totally
unavailable near me (libraries, bookstores, etc). I ordered a copy
from amazon, but I'm worried that it won't arrive in time.

So they have renamed book in addition to watering it down.

If you can get a hold of an edition around 1990, the first few
chapters should give just the right type of information you need. The
official name in those days was "The ARRL Handbook for Radio
Amateurs", which might help you locate it in a library.

Unfortunately about 10 years ago the handbook was reorganised and
watered down, making it less suitable as general electronics text
book.

Paul
 
M

Mike Switch

Jan 1, 1970
0
So, can anyone suggest other references that are either available
online, or likely to be in Barnes and Noble? I'm looking for
introductory overview type information rather than detailed
down-to-the-last-electron info.

I like this book for a quick refresher on topics I need to review:

The Benchtop Electronics Handbook, Veley, Victor F.C., McGraw-Hill

Probably available at Amazon, but possibly at your local library also.

HTH,

Mike
 
F

Fred Bloggs

Jan 1, 1970
0
Joe said:
How about applying for a job for which you are actually qualified? If
you cannot answer these questions without cramming even your digital
"skills" are bogus. I seem to recall your last job at Digi-Frame (?) and
your heart-rending series of accounts of their financial difficulties
and your resulting "ethical" dilemmas. Where are your ethics now?

EXCELLENT RESPONSE! It is not like he is trying to review or "brush up",
but the effort is more along the lines of acquiring material for an act.
He should come clean and tell the interviewer he has no interest in
analog whatsoever, doesn't know a thing about it, and doesn't want to
know anything beyond the most essential information required for an
application- the analog portion of anything he works on is best done by
someone else.
 
F

Fred Bloggs

Jan 1, 1970
0
Al said:
There's no reason to be condensending. And stereotyping an entire
generation as 'cheaters' is just arrogant.

Nah- it's called being realistic- most of your riffraff generation
signed up for an EE major to get a "high paying" job- and aren't worth a
sh_t- 80% are out of the industry within the first five years of
graduation. I'd say that 90% of the present undergraduate population
wouldn't have qualified for *any* education beyond high school by even
1960 standards...they just don't have the endowment or work ethic to
succeed in a legitimate curriculum.
 
C

CFoley1064

Jan 1, 1970
0
Subject: Job interview help! Good analog primer?
From: [email protected] (Lewin A.R.W. Edwards)
Date: 5/12/2004 12:22 PM Central Standard Time
Message-id: <[email protected]>

Hi all,

I'm going to a second-round job interview next Monday, and I've been
forewarned by the first-round interviewer that I will be asked
questions on analog and RF topics (basic op-amp circuits, transistors
used in switching and amplification apps, superhet receivers and AM
transmitter).

I'm not being expected to demonstrate extreme skill (my primary
function is firmware and digital, analog and particularly RF are not
my strong point - and I made this clear to them before ever coming in)
but I would like to have as good a briefing as possible. He
recommended the ARRL Radio Comms handbook, which is totally
unavailable near me (libraries, bookstores, etc). I ordered a copy
from amazon, but I'm worried that it won't arrive in time.

So, can anyone suggest other references that are either available
online, or likely to be in Barnes and Noble? I'm looking for
introductory overview type information rather than detailed
down-to-the-last-electron info.

AAMOI: the interview technique he used was, among other things, to
give me a large mixed-signal schematic and a stuffed board, and leave
me to look at it for 15 minutes, then I had to describe as far as
possible the function of the various blocks in the circuit. I did
tolerably well on that. But the second part of the test was 15 minutes
with a snippet (~10 pages) of assembly source for a micro I'd never
used. THAT was fun. Didn't do at all well on that. Oh well. I hope the
aim was to observe behavior under stress :)

Any assistance will be karmically rewarded :)))

Hi, Mr. Edwards. If I could add a few suggestions...

* On follow-up interviews, they're interested in finding out other things
besides your ability to pass an employment test. If he suggested the ARRL
Handbook, you *have* to get that, and look it over. Get the most recent
version (don't be dismayed by the high price -- if you're making this a career
and you're serious about being an EE, the book is a necessity and will pay for
itself many times over, whether you get this job or not). One of the goals of
the second interview may be to see if you can follow instructions.

* If you didn't ask for Fed Ex, get back to Amazon immediately and order one
with the fastest possible shipping. You should get it by Saturday morning at
the latest, which should be enough time to scan through the book, looking at
the areas they specified. Put on a pot of coffee, and dedicate the weekend to
it. You'd be amazed how much is in that wonderful book. When the other one
arrives, you can return it.

* Everyone who gets an EE has, of necessity, some gaps in their knowledge
base. That's to be expected. After all, you've only got four years, and
there's so much else to do in college. Long term, the junior engineer who will
be the most successful fit is the one who is willing to spend some of his own
time to get up to speed, and who will accept direction from the mentoring
senior engineers. It seems to me you've been asked to spend some of your own
time to get up to speed and accept some direction from a mentor here.

* While you're at amazon, get The Art of Electronics, too. It's also a great
investment.

Sorry about the rather gruff reception you've gotten here. Engineers, even
good ones, can be like that sometimes. The thing is, nearly all engineers
respect proven competence, and that will develop with time. Just hold your
head up, keep working, and do the best you can -- you proved in college that's
good enough.

Good luck with the interview (luck being the residue of hard work)
Chris
 
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