Still hanging in with MIT's 6.002x?

[MikeK]

It has gotten more math intensive, but I really find it interesting to see the derivation of the frequency formula for an LC tank circuit.

How's everyone holding out?  The midterm opens later today.

[HLA-27b]

had no time recently
two weeks worth of catching up to do in less than a week
no going out for a few days it seems....just like the the old days at school

[olsenn]

I don't find it all too bad; however, keep in mind I have taken university electrical engineering already. I must ask of all the experienced engineers here though; do any of you actually use transistor equations in real life? I mean, transistors fabricated in an ASIC plant may follow an equation quite accurately, but from my experience with transistors, the linear region is never very linear, B/hfe varies GREATLY, not only just by transistor to transistor (even ones from the same batch) but also by collector current and many other factors. I don't really see the point in studying all the large and small signal equations when in reality, if you need a representation of how the current changes with base/gate voltage, you'll need to look at graphs (datasheet or more accurately by measuring it yourself).

[grumpydoc]

Unfortunately the time I could spend on the course fell at precisely the wrong time in terms of more complex maths - which I was going to have to revise. In the end it was either spend a week solid on the course to catch up or do other stuff and other stuff won. Hey Ho!

[cybergibbons]

Yep, still going. As with olsenn, already have an EE degree and I'm just refreshing and looking at things from a different perspective.

[MikeK]

I have to admit that it's very interesting to see how things are derived, like the LC tank frequency formula.

But I see a huge gap between what I'm learning in 6.002x and practical application to building cool stuff, like Alan Yates' Advent Calendar of Circuits.

[IanB]

But I see a huge gap between what I'm learning in 6.002x and practical application to building cool stuff, like Alan Yates' Advent Calendar of Circuits.

Although I have not been following 6.002x that closely, I think what you learn there is a kind of "deep knowledge" that ultimately would help you better appreciate the practical stuff and intuit how it works (or doesn't work). Especially if you are trying to come up with your own designs. Sometimes it takes a while to build deep connections in your mind between pieces of knowledge that at first sight don't seem that relevant to your everyday experience. Just my 2c.

[slateraptor]

I don't really see the point in studying all the large and small signal equations when in reality, if you need a representation of how the current changes with base/gate voltage, you'll need to look at graphs (datasheet or more accurately by measuring it yourself).

Oh come on now.

...B/hfe varies GREATLY, not only just by transistor to transistor (even ones from the same batch) but also by collector current and many other factors.

There are certain topologies and techniques for reducing an amp's susceptibility to large variances in beta...but if you don't work out and study the small-signal equations how would you know that unless someone else has explicitly told you, and how would he know that without having worked out the equations for himself to point him in the direction of this not-so-obvious sol'n, ad infinitum.

[Zad]

I'm going to write a blog post about this I think, I have lots of thoughts on the matter and it would rather clutter the discussion up if I rambled on at length here. I am one of those undertaking 6.002x. My background is in electronics design, but my first degree was not pure electronics but more widely based, incorporating systems and software development. Hence, I didn't get all the in-depth theoretical background which a "pure" electronics student would.

The last time I did any calculus was nearly 20 years ago. Yeah, that's proving rather testing for me. I'm still hanging in there, just. Weeks 6 and 7 have been extremely difficult for me, purely because of the maths. I am not at all confident about the mid-term exam! I started out before the course started, with the aim of "reading around" a subject before the week's lectures. This worked fine right up until week 2. I don't have £70 spare at the moment, so have to read the textbook on-line, which I find to be awkward. I can see this being a big log-jam for many students. I appreciate the fact that printing text books is not cheap, but there are many flexible printing services now which can print on demand, for a sum much lower than £70. Right now, I am tempted to skip the exam rather than get a poor score, but keep on with the lectures. In the hope that I will be able to re-take the course on the next run. If I do re-take it, then I will be running through the MIT Differential Equations course first.

The format they are using for the lectures is rather messy, trying to cram scribbles onto a small screen rather than a conventional black/whiteboard. Other than that, it is almost identical content to existing MIT YouTube lectures. One notable difference being the sound quality, which varies from okay to extremely muffled and indistinct. Consideration really should have been given to generating clear presentation slides, perhaps even generating a formal script. This might help reduce the number of times Prof Agarwal repeats himself (in Week 7 he states the same thing four times, on several occasions).

Pacing. 10 hours study a week is probably about right for the demands of the content, possibly a little conservative. This doesn't sound much, but when you consider it is 25% of a working week, or 1.5 hours every day, then it starts to look rather too much. Skipping one day's study means finding a day with 3 hours free.  Over the last month I have had some family health problems which had to take priority, with the result that I have had to skip through things just to keep up. Unfortunately, the structure is that of a chain, which means that all subsequent material becomes considerably more difficult.

If I were running this course, I would either run 1 lecture a week (instead of 2) or run a truly flexible system, paced to the student's ability. There is no reason why this should not be possible in the future, other universities run similar systems. Basically, it needs a pause button, or a course length much longer than that of the real world 6.002.

A few weeks ago on Adafruit's "Ask An Engineer" LadyAda (Limor) was chatting to Woz (Amanda Wozniak). They are both MIT graduates and were asked for their thoughts on 6.002x. I thought their comments were very interesting. They both agreed that 6.002 was known as the "weed them out" course, and is responsible for a number of drop-outs every year. The first half being particularly difficult and dry. Amanda admitted that at one point she was very close to leaving the course as it was so demoralising. They both seemed slightly puzzled that MIT had chosen this course as a pilot.

I'm a little puzzled at the course structuring. Running from circuit analysis, through Mosfets (no coverage of bipolar) then capacitors and inductors. The way I was taught (and the way I have seen it at many other UK universities) is to cover simple passives first, then move into filters. After that it is diodes, transistors, op-amps etc. I agree with the previous poster, concerning how they focus on one part of the theoretical model without explaining other important aspects.

Before anyone says how MIT is special etc, my uni (Leeds) has a pretty decent reputation, and has its share of Nobel laureates too. I don't buy the argument that MIT is somehow on a different planet and inherently better than everywhere else. Sometimes the emperor really is, if not naked, then wearing bermuda shorts. The course as a physical entity is probably sound (if in need of a few tweaks) but the wholesale conversion to online delivery has shown up deficiencies. I guess this is why it is being run!

I can't talk about 6.002x without mentioning cheating. The official forum pretty much has verbatim answers for the homework, and other sources have them even more explicitly. Given the frustrating method of answer entry (which sometimes take longer than working out the actual answer) this is probably vital.

[gregariz]

Before anyone says how MIT is special etc, my uni (Leeds) has a pretty decent reputation, and has its share of Nobel laureates too. I don't buy the argument that MIT is somehow on a different planet and inherently better than everywhere else. Sometimes the emperor really is, if not naked, then wearing bermuda shorts. The course as a physical entity is probably sound (if in need of a few tweaks) but the wholesale conversion to online delivery has shown up deficiencies. I guess this is why it is being run!

I don't buy it either, in fact I looked at their EE program and thought it all looked fairly average in comparison to some of the state programs and other programs overseas. It kind of reminds me of the Japanese system. The hardest thing is getting in, and then your career is often defined by where you went.

When I go off to various IEEE conferences I almost never see these people presenting and the really interesting stuff seems to be from a wide spread of universities. I've worked with them on the job and they were no different to anyone else, some good some not so good. I haven't seen crap though, so entry standards are guaranteeing that. Money is on their side though, their access to venture capital for their grads and entrepreneurship advice seems to be outstripping anyone else.

[MikeK]

Just finished the 6.002x midterm.  It was easier than I thought it would be.  Even easier than I thought it should be.  The OCW material shows that previous 6.002 (regular) classes had tests that were much more difficult and had more problems.

[Baliszoft]

I had to finish after the fourth week, it took too much time from me :-(

[McMonster]

I'm considering leaving this now, I have so much other work to do that I barely had time to just go through the lectures and do the homeworks and labs. I'll probably just ignore the certificate and still watch the lectures though, they're simply great and I learned a lot of basic things that were bothering me since I started dabbling in hobby electronics. Sometimes I have an urge to send the lectures to some of my university's lecturers (I'm studying computer science), they should learn how to do a course in an interesting way.

[ziq8tsi]

I finished week10 late last night, so I am now up to date for the first time in the course!  (I enrolled a couple of weeks in but before the first deadline.)

Compared to a few other recent online Stanford, Coursera, Udacity courses I have taken, and even allowing for my CS background, MITx 6.002x is by far the most work.  The lectures are easy to follow, but applying the techniques to the homework problems is often a challenge.

[free_electron]

i started it in beta version then gave up. i found a couple of mistakes ( one was in the simple resistor divider where you have to find out the worst case scenario for resistors that are 10% off.. well they failed to take into account that the worst case is when one goes 10% up , the other 10% down.... they think a resistor with 10% tolerance means it can go 5% up and 5% down. While in reality a resistor specced at 10% means  +/- 10%. it can go 10 up and 10 down... so one goes 10% up , the other 10% down....)
i pointed this out to them... no answer , no fix... pretty poor ...

[alm]

Seems to be fixed by now:

The "tolerance" means that if you buy a 10% 390 ohm resistor you can be sure that its resistance is between 351 ohm and 429 ohm.

Edit: fixed Omega symbols. Dear forum, let me introduce you to Ms Unicode.

[aluck]

Thinking about giving up. Week 9 Math is beyond my comprehension.

[MikeK]

Week 10 homework was very painful for me.  But there's merit in persevering.

[Architect_1077]

Well, I recently began studying 6.002 from the MIT OCW at my own pace, watching the videos and going over the materials. But I'm confused... how is it you guys seem to be following it at a regular schedule?? 

[MikeK]

Well, I recently began studying 6.002 from the MIT OCW at my own pace, watching the videos and going over the materials. But I'm confused... how is it you guys seem to be following it at a regular schedule?? 

6.002x is different than the 6.002 material available through OCW.  6.002x is a pilot course for MITx, and does adhere to a schedule, and has graded homework and exams.

[Architect_1077]

Lovely! Totally ignored this!
Well, I'll just keep at the OCW for now as I'm way behind.

[MikeK]

There may be another offering of 6.002x this summer or fall.  So you'll be well-prepared for it.

[MikeK]

I forgot to add: The 6.002x professor recently announced that the materials would likely be available indefinitely.  So, you can still sign-up, go through the material, work through the exercises, labs, and [probably?] submit the homeworks and exams; they'll just be counted as late.

[Noize]

Just started to get my head around week nine. Finding it hard but making progress. 

Week 10 homework was very painful for me.  But there's merit in persevering.

[olsenn]

The course is over now; what did everyone think. I didn't do half of my homework assignments or labs, so I only ended up getting 81% (B) but I thought the course material was decent enough. As always though, too much emphesis on reverse engineering and not enough on design.