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Basics of EE!

  1. Mar 19, 2012 #1


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    Hey all....I've recently been working with some F.E. candidates and I notice they are very weak on the basics of electrical engineering. So I had to force these things down their throat. If you are a college student specifically....you need to know these backwards and forwards!!!! You should be able to concisely describe the following in a couple sentences!!! If not....ask questions now....the concepts are very simple and I consider them the foundation of EE:

    Voltage Divider
    Current Divder
    Equivalent series resistors
    Equivalent parallel resistors
    Current thru resistors (current does not go across resistors!)
    Voltage across resistors (Voltage does not go thru resistors!)

    To all aspiring students....can you clearly and concisely describe each of these in a couple sentences? In other words...if you were standing in front of 1,000 people and you had to explain all these....could you do it? If not....take a step back and learn them!!!

    And yes...you wouldn't believe how many active electrical engineers that don't get these basics!!!

    Please....ask questions....or describe them on this forum. And yes, there certainly are more things...but you can't move on until you have these!
  2. jcsd
  3. Mar 19, 2012 #2
    Most of these concepts are not even college level EE concepts. People learn these in high school physics.

    I wonder if its possible to be so caught up in abstract and advanced topics that you forget the basics.

    Sometimes if I'm studying math, and heavily involved in doing a math problem, I could probably forget my multiplication tables.

    This can also happen when I'm put on the spot. Sometimes the most obvious things leave my head when I'm not in the proper mental state.

    But those are probably just excuses for your interviewers, and it would be embarrassing to not know ohm's law at an interview for a EE position.
    Last edited: Mar 19, 2012
  4. Mar 19, 2012 #3


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    Ya....it's scary how many EE types don't know this stuff....mind boggling.

    Note to aspiring students: Once you clearly learn these things... you can never forget them till the day you die. They will never go away....and they will always be true!

    It would be different if these people had forgotten some of the basics.....but some people have not a clue in regards to these basics....and they have electrical engineering degrees!!!

    One more spot I notice extreme weakness is in voltage drop.....especially in regards to no current flow. For example when there is a voltage source in series with resistor into the bottom terminal of an op amp.....V+ for example. They just dont get how V+ = V- = the voltage source.

    Transistors is another one....when the transistor is off.....VCE will equal the collector voltage! No current....no voltage drop across the collector resistor.....
    Last edited: Mar 19, 2012
  5. Mar 21, 2012 #4
    Well, forgive me if I find your story unbelievable. I have been a practicing EE for 33 years, I returned to grad school recently & I'm in the final stage of my Ph.D. program. I have yet to meet an EE who doesn't understand how to compute a voltage drop. Re transistors, any hardware EE practitioner knows what to expect from a transistor when it is turned off, or on, for that matter.

    If such EEs as you describe appear from time to time, my guess is that they got their degree decades ago, but have been practicing software ever since, with little to no hardware experience. It's possible that the basics may have escaped them.

    But any EE who has been practicing hardware design for any length of time is much more astute than you seem to think. The scenario you just described is simply not believable. No offense.

  6. Mar 21, 2012 #5


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    LOL!!! I hear ya bro!!!

    But when 5 of the people I work with who recently graduated are standing in my office with a scared, no clue on their face....it's real.

    Feel free not to believe me...but I have no reason to lie.

    I am just as astounded as you are.

    It's shameful...it's embarassing. I told them to sue the schools they went to.
  7. Mar 21, 2012 #6
    I actually believe this, with the public school in US, you have to work to fail the class. I was a manager for so many years doing hiring. I device a test...a very simple test for EE and technicians.
    1) An op-amp with inverted configuration with feedback resistor Rf and input resistor R1. I just feed an AC signal to R1 and asked to draw the output. The only trick is I an a resistor R2 to the summing junction and tie to a DC voltage. The question is to have them draw the output. You'll surprised how many fail.
    2) Two D flip flop clock by a CLK. One with /Q connected back to the D input as a divided by two. The second DFF take the Q output of the first divided by two and feed into the D input. I just want them to draw out the timing diagram of the Q of the first DFF and the second DFF. It is nothing more than a divided by two and a pipeline. You'll be surprised how many struggled on this.
    3) Bonus question. An NPN BJT in common emitter configuration with resistor divider bias. I just ask them to label the emitter voltage, collector voltage and with an input waveform, have them draw the output waveform.

    This is questions that any student graduated in AA degree like from Heald College can do. This is something you learn right at the beginning. You'll be surprised how many people can't do it. For EE, if they cannot answer the three question, the interview ended.

    The public education system in US is so bad. They worry about political correctness rather than education. In the past years, kids get spoiled, they get praised for doing just ok. They want the kids to feel good. Everyone want to be in high places but rather play video game than to study. Look at the Silicon Valley, majority of engineers are from foreign country. Kids here mostly are too lazy to button down and study. They just want to easy way out.

    I mostly study on my own. I was planning to enroll in San Jose State. But after I communicated with a few professors, I change my mind. They use EM book by Ulaby!!! You don't learn EM from that book!!! It is a good book....for pre-EM!!!! I know they only cover what's in the book because I got their homework and even the exams to look at!!!

    Then I was planning to enroll in the PDE class. They use the easiest book by Asmar. And at that, they skip all the 3D problems, they only spend two weeks on Bessel's and Lagendre Functions where that are the meat of the problems using cylindrical and spherical coordinates. I spent three months just on these two!!! When I asked how far they cover the Strumn Louville and some others, the professor said" Oh well......it really depend on the class.........some go farther, some don't"!!!!
    What kind of class is this? So if the students are lazy, then you cover less!!!

    I decided to study both on my own, I don't trust them. I don't even trust the books they use. I have to work over using Cheng and Griffiths on EM, Strauss on PDE to feel that I learn enough. San Jose State is not considered to be a bad college for EE!!!! I wonder what is consider bad school.

    I hired a BSEE and a MSEE candidate from SJSU, they really sucked!!!!

    I tell you, I can go on and on in how bad the public schools are and how bad a lot of students are. People think we have all the brains and talents.......think again. Go to any company and look at their EE dept. Look at how many are born and bread here.
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