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157 points tdhttt | 69 comments | | HN request time: 1.255s | source | bottom
1. pclmulqdq ◴[] No.45125831[source]
EE encompasses a lot of "engineering that takes hard math" at a professional and research level (similar to "hard CS," just different fields of math), so it is very hard to do as an undergrad, when your background in complex analysis and E&M is weak.

Early classes on circuits in EE will usually take shortcuts using known circuit structures and simplified models. The abstraction underneath the field of analog circuits is extremely leaky, so you often learn to ignore it unless you absolutely need to pay attention.

Hobbyist and undergrad projects thus usually consist of cargo culting combinations of simple circuit building blocks connected to a microcontroller of some kind. A lot of research (not in EE) needs this kind of work, but it's not necessarily glamorous. This is the same as pulling software libraries off the shelf to do software work ("showing my advisor docker"), but the software work gets more credit in modern academia because the skills are rarer and the building blocks are newer.

Plenty of cutting-edge science needs hobbyist-level EE, it's just not work in EE. Actual CS research is largely the same as EE research: very, very heavy on math and very difficult to do without studying a lot. If you compare hard EE research to basic software engineering, it makes sense that you think there's a "wall," but you're ignoring the easy EE and the hard CS.

replies(7): >>45126229 #>>45126357 #>>45126514 #>>45127402 #>>45127675 #>>45128168 #>>45128950 #
2. amelius ◴[] No.45126229[source]
This is especially true because for doing most _hard_ EE work, you really need access to a fab, and so a lot of money. This is not really the case for most hard CS work.
replies(4): >>45126321 #>>45126341 #>>45126394 #>>45127024 #
3. nudgeee ◴[] No.45126321[source]
By fab you mean lab, then agree.

Fabs are specific to the manufacturing of integrated circuits.

EE encompasses more than just manufacturing of ICs, for example research and applications in radio propagation and EM/wireless, signal integrity, antenna design, coexistence/desense, advanced power electronics, control systems, simulation/solvers, etc.

replies(2): >>45126396 #>>45128115 #
4. pclmulqdq ◴[] No.45126341[source]
Fabs are only part of this, and not universal in EE research at all. However, almost all serious EE research requires at least $100k of lab equipment of one kind or another.
replies(1): >>45127417 #
5. carlmr ◴[] No.45126357[source]
>Early classes on circuits in EE will usually take shortcuts using known circuit structures and simplified models.

Might just be me, but I found it all clicked when we started learning the fundamentals underneath these abstractions. For me it was harder in the first classes because it's about memorizing poorly understood concepts, my brain prefers logically deriving complex concepts as a learning method.

replies(2): >>45126439 #>>45126604 #
6. sevensor ◴[] No.45126394[source]
“Things you can only do in a fab” is but a subset of “hard problems in EE.” How many people actually understand induction motors well enough to design a better one? Or how about antenna theory? The math makes most people’s eyeballs melt, and the space of possible antenna designs is utterly unfathomably huge. And then there’s acoustics, which is just like antenna theory except the math is sideways. I could go on. Control theory. Analog signal processing. Digital signal processing. Biomedical.

I say all this as a recovering semiconductor engineer: EE is a huge field. I can’t think of a subdiscipline where we’ve run out of new ideas to explore, and most of them don’t require bucketfuls of HF. The real problem is that the financial rewards are relatively small, the math is ferocious, and there are so few practitioners, let alone experts doing research.

7. amelius ◴[] No.45126396{3}[source]
This is true, although for wireless applications you can follow the recommendations of the IC vendor and the remainder of the work is RF-engineering, not research. That's why I said fab, not lab. But yes, you are right to a great extent. The main point is that the hard EE work can be prohibitively expensive for individuals and smaller companies.
replies(2): >>45126431 #>>45126701 #
8. pclmulqdq ◴[] No.45126431{4}[source]
I think you're oversimplifying this. Lots of RF research is done with a DAC, an ADC, an FPGA, and a frontend made of discretes (sometimes also with off-the-shelf boxes connected with SMA connectors). A lot of power electronics research is done with microcontrollers and discrete parts. Digital circuits research often stops on an FPGA or in a simulator.

You can do a lot of actual original work without a fab.

replies(1): >>45134974 #
9. stephen_g ◴[] No.45126439[source]
Yeah, this kind of idea is why I’m dead against using things like the hydraulic analogy in early EE for anyone who is ever going to want to do more than the ‘hook some things up to an Arduino’ (or probably ESP32 these days) kind of level electronics.

The gaps between the analogy and the real world actually make it harder to understand the fundamentals and just confuse people when you get to a deeper level understanding. It requires more unlearning than is worth it for the slight benefit of making the concepts slightly more intuitive to understand at the beginning.

replies(5): >>45126493 #>>45126508 #>>45127440 #>>45128957 #>>45133630 #
10. junon ◴[] No.45126493{3}[source]
Once I ditched the hydraulic analogy and really tried to internalize charge, current, voltage, etc. is when I finally started to understand why the hydraulic analogy "works" but only for people who already understand electricity.

Electricity behaves in many ways just like water (just at a significantly faster time scale) but I don't think it actually helped me learn how it all worked to start with.

replies(2): >>45127233 #>>45132815 #
11. marcosdumay ◴[] No.45126508{3}[source]
Hum... The hydraulic analogy is for school kids to learn what electricity is. If you are creating circuits to hook into an arduino, you should have moved from it already.
replies(3): >>45126537 #>>45126549 #>>45126888 #
12. markus_zhang ◴[] No.45126514[source]
Interesting. My approach to hobbyist EE (actually embedded) is:

1. Learn soldering

2. Treat circuits like black boxes. If I need X amount of Y, e.g. I need a circuit to smooth the voltage, I pick one black box with adequate attributes.

However this is pretty introductory and I have no idea how to learn to fix old consoles. Sometimes it’s just a broken capacitor but I first need to figure out which part is broken.

replies(3): >>45128763 #>>45129339 #>>45132207 #
13. not_that_d ◴[] No.45126537{4}[source]
I feel insulted.
replies(1): >>45128915 #
14. lukan ◴[] No.45126549{4}[source]
I believe school kids should be already creating circuits and hooking them up to arduinos.
15. sevensor ◴[] No.45126604[source]
My biggest criticism of EE pedagogy is that it tends to proceed from abstractions and then derive the whole world. This makes it a bit of a slog for a lot of students. I’d like to see an application-first approach that builds up principles from observed behavior. Like, measure the slip in an induction motor and then work out what’s going on there, instead of deriving motors from Maxwell’s equations.
replies(6): >>45126618 #>>45128273 #>>45128460 #>>45131520 #>>45132296 #>>45143424 #
16. carlmr ◴[] No.45126618{3}[source]
That's a good point, too, I had a bunch of abstractions without applications in my head.
replies(1): >>45133587 #
17. nudgeee ◴[] No.45126701{4}[source]
Sibling poster did a good job explaining how research relies on labs.

Agree that complex EE work can be expensive for individual and smaller companies, indeed :)

A comment on the application side:

> "[..] for wireless applications you can follow the recommendations of the IC vendor and the remainder of the work is RF-engineering"

Zoom out to the system level, and you cannot just rely on IC vendor recommendations, and this kind of engineering can still require access to $$ labs.

Similar to complex software systems: for example take a large scale distributed system made out of many individual frameworks and services. The system as a whole may now exhibit emergent behaviour, and have failure modes due to the complexity of the system.

Same happens in complex EE designs, your design might pack in multiple cutting edge RF radios such as mmWave, UWB, with bespoke power amplifier, detection and antenna designs. Add in EM from multiple clock domains, high power distribution circuits, digital noise from FPGAs/CPUs, and EM from nearby sources. You can easily have noise couple from sources causing unintended issues in other subsystems. The vendor may say "keep a way from sources of noise", but your application may still be to engineer a solution that fits in the design envelope of a modern smartphone. The system level design needs to be engineered for EMC and coexist/desense, and validated which takes a ton of lab simulation and measurement/characterization work.

18. kevin_thibedeau ◴[] No.45126888{4}[source]
It is a flawed analogy but it behaves like a fluid more than most realize:

https://youtu.be/2AXv49dDQJw?feature=shared&t=1248

replies(1): >>45128885 #
19. hwillis ◴[] No.45127024[source]
Does radar or radar reflection not count as "hard"? There's a lot more to electronics and electrical engineering than ICs.
20. r_lee ◴[] No.45127233{4}[source]
This is a common problem in all fields IMO. It's easy for many to fall into the "It's like X" but it only makes sense if you already have the information needed in your head to connect the dots

Which is why I also don't generally like analogies and the kind

21. dfawcus ◴[] No.45127402[source]
Yeah - there was a massive filtering of the students between the 1st year entry, and the second year at my Uni. Largely down to people unable to handle the (not terribly) complex maths at that stage.

I knew a number of folks in the first year who were very good at practical electronics, having come in from a technician side, but simply gave up due to the heavy maths load.

It got more complex when doing Control Theory, what with Laplace and Z transforms, freq domain analysis, and the apocryphal Poles and Zeros.

Further culling ensued at that point.

replies(2): >>45128577 #>>45131315 #
22. wildzzz ◴[] No.45127417{3}[source]
That's definitely an unfortunate part of EE, the hardware required to design hardware is expensive. CS requires a laptop and maybe some time on a server or a big GPU cluster, expensive to own but very cheap to rent.

I think the explosion in availability of inexpensive microcontrollers and FPGA dev boards have made it much easier for people to get into hardware design without spending a ton of money. This has also made it cheaper to buy high end test equipment, you don't need to buy a $3k Keysight oscope when a cheap Chinese USB oscope works just as well with plenty of features built-in for free. Obviously a proper academic or corporate research lab is going to be a lot different than a well-equiped hobbyist lab but the difference is not as stark as you'd imagine.

23. therealcamino ◴[] No.45127440{3}[source]
I had a CS professor as an undergrad who would teach a couple of advanced seminars in his own research area. His approach to those simplifications was to announce, "I'm going to lie to you now, but just go with it and I promise that later we're going to learn the real truth." I liked that as a compromise, to make some practical progress, but not to mistake the simplification for full understanding. (And he wasn't rigid about it -- if somebody would ask a deeper question he'd happily answer it to some level and then get on with his plan.)
24. morpheuskafka ◴[] No.45127675[source]
> Plenty of cutting-edge science needs hobbyist-level EE, it's just not work in EE

But aren't there a lot of actual hardware products that are "simple circuit blocks connected to a microcontroller"? Like a toaster, shaver, keyboard, etc. If that's not "work in EE" then what is it classified under? It's not CS either.

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25. throwup238 ◴[] No.45128115{3}[source]
> Fabs are specific to the manufacturing of integrated circuits.

In EE the factories that produce PCBs are also called fabs.

26. buckle8017 ◴[] No.45128134[source]
Computer engineering is the degree for that.
27. alnwlsn ◴[] No.45128168[source]
I'm sure part of it is that EE claims probably the widest range out there. You can have kilovolts or microvolts, but mostly the same rules apply. Or you can learn how to power a small sensor for years off one small battery, or how to power a country. I don't know many other disciplines that can lay claim to 10-15 orders of magnitude.

At most levels, software will be in there somewhere, even those fake flickering candle LEDs have RAM, ROM, and a processor these days.

replies(1): >>45128446 #
28. idiotsecant ◴[] No.45128273{3}[source]
There isn't enough time. A leisurely exploration from observations is what you do on your own time. School has a certain amount of material to convey in a certain time. That means learn the axioms and rules as best you can and get to work paying off that enormous student loan.
29. ForHackernews ◴[] No.45128446[source]
I feel like astronomy probably wins, the magnitudes are literally astronomical.

The Perseus Cluster of galaxies is estimated[0] at something like 816,592 light years in diameter, so that's 10^21 meters, and on the other end 2008 TC3[1] is an asteroid 4.1m across.

[0] https://www.universeguide.com/galaxy/perseuscluster

[1] https://thesolarsystem.fandom.com/wiki/2008_TC3

30. tekla ◴[] No.45128460{3}[source]
Massive waste of time. So much happens in a way that is not intuitive nor easily observable that starting from the math is much better.
replies(2): >>45128847 #>>45129681 #
31. pkaye ◴[] No.45128519[source]
That would be Computer Engineering. Its somewhere between EE and CS.
32. Eggpants ◴[] No.45128577[source]
I went into EE wanting to learn how to design CPU’s and thought the analog side would be boring.

However, control theory turned out to be my favorite class. Learning how negative feedback loops are everywhere was an eye opener.

Also learning Laplace transforms was one of my first “holy shit this is freaking clever and cool” moments. Just like how parity bits in data streams can be used to detect AND correct errors.

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33. petsfed ◴[] No.45128623[source]
The actual electrical engineering involved there is the sort of thing that an early-career engineer could bang out in an afternoon. Maybe a day or so for the PCB designer. The more time consuming part might be managing the regulatory compliance testing.

Most of the orgs I worked in building simple circuit blocks connected to a microcontroller either farmed out the actual EE work to contractors or design houses or had 1 EE for like 20 different projects.

34. toast0 ◴[] No.45128763[source]
Fixing old consoles is roughly...

a) inspect for obviously damaged components. Capacitors that leaked, chips that released the magic smoke, etc.

b) confirm voltages are good

c) inspect the inputs and outputs of the ics to see if they're doing what you expect

d) depending on the boards involved, a lot of checking if pin A is electrically connected to pin B when it should be. Sometimes traces get broken and need to be fixed up.

35. bee_rider ◴[] No.45128847{4}[source]
The blog post describes the problem with this strategy, I think—the author was already pulled over to the CS side because they could just throw together a web app that people could actually interact with, day one.

If you start with easy circuit models, at least the labs can put together something tangible in the first couple semesters, to keep people interested.

And, I mean, a lot of engineering students end up going into sort of technician-y jobs, so keeping the hands-on spark alive has a lot of value, IMO.

36. buildbot ◴[] No.45128876{3}[source]
Same on the laplace transforms. I was kinda mad we had learned any other way. It was a lot easier than whatever we were doing before mathematically!

I wonder, how much control theory is there in CPU?

replies(2): >>45131071 #>>45133238 #
37. marcosdumay ◴[] No.45128885{5}[source]
Electricity behaves a lot like a fluid. But not much like water or air, so there's little point in using it as an intuitive analogy.
38. marcosdumay ◴[] No.45128915{5}[source]
Instead, if you still use it, just drop it because it's probably holding you back.

And if you managed to move ahead in hard mode, you shouldn't feel insulted.

39. jsmith45 ◴[] No.45128950[source]
> Actual CS research is largely the same as EE research: very, very heavy on math and very difficult to do without studying a lot.

That is largely true of academic research. A critical difference though is that you don't need big expensive hardware, or the like to follow along with large portions of the cutting edge CS research. There are some exceptions like cutting edge AI training work super expensive equipment or large cloud expenditures, but tons of other cutting edge CS research can run even on a fairly low-end laptop just fine.

It is also true that plenty of software innovation is not even tied to CS style academic research. Experimenting with what sort of perf becomes possible via implementing a new kernel feature, can be very important research but isn't always super closely tied to academic CS research.

Even the more hobbyist level cutting edge research for EE will have more costs, simply because components and PCBs are not exactly free, and you cannot just keep using the same boards for every project for several years like you can with a PC.

40. bee_rider ◴[] No.45128957{3}[source]
The hydraulic analogy always sort of confused me because, like, fluid mechanics are real complicated. So, I always had this gut feeling question of like, can we actually end up with a hydraulic analogy that is exactly as complicated and electricity and magnetism? If we push the analogy beyond what is intended?

Is it an analogy or are both models expressions of some underlying model of potentials and flows, and we happen to have more hands-on experience with water?

replies(1): >>45133778 #
41. choilive ◴[] No.45129325{3}[source]
Control theory was also one of my favorite classes that a low of software people should learn (at least the very basics). So many hand rolled heuristically driven if/else type systems that can simply be replaced more reliably with a PID.
replies(2): >>45132020 #>>45132403 #
42. choilive ◴[] No.45129339[source]
Fixing consoles is also treating circuits like black boxes :) . just gotta know what the black boxes are
43. sevensor ◴[] No.45129681{4}[source]
So set your sights lower? A lot of BS EEs exit the process understanding neither Maxwell’s equations nor which end of a soldering iron to hold. The degree demonstrates that they are good at abstract symbol manipulation, and that’s not nothing, but it’s not very intellectually fulfilling and it filters out a lot of people who could be good engineers.
44. HeyLaughingBoy ◴[] No.45129968{3}[source]
I never really "got" control theory until about 10 years after graduation.

I was working as an SW Engr and taking a set of courses towards a Mechatronics certificate (my employer did a lot of motion control work) and I had to basically take updated versions of the same classes. The lab instructor was an about-to-retire engineer from Schunk, and he did an amazing job of explaining what the theory meant in terms of real-world behavior. That's when it all finally sunk in and I could look at the math and "see" how a mechanism would respond.

45. pclmulqdq ◴[] No.45130961[source]
It would have been better phrased as "research in EE." There's no research involved in building a toaster.

Another commenter pointed this out, but those products take about 1-2 days of engineering time.

46. zhemao ◴[] No.45131071{4}[source]
In computer architecture / digital ASIC design there's zero control theory. There's not much mathematics in general.
47. underlipton ◴[] No.45131315[source]
I sometimes wonder if math suffers from a bit of basketball syndrome. That is, I'm sure there are dozens of potential Muggsy Bogues-esque players out there, but the game's meta continues to drift ever towards who coaches and trainers know how to coach and train, which is tall dudes.

There might be a structural issue if you have a bunch of guys coming in from the technician side, as you say, who almost all get filtered out. You might need remedial classes, a different curriculum progression, something. Or else recruitment standards/expectation-setting are wacked-out.

48. renox ◴[] No.45131520{3}[source]
I remember having two class about networking, the first one was top down, it was awful, the second one was bottom up, everything clicked.
replies(1): >>45137257 #
49. Karrot_Kream ◴[] No.45132020{4}[source]
I've played around with this over the years in my career but have found that tuning PID loops is very tricky, much trickier than creating a soup of if/else clauses and much less auditable to those who don't understand the math.
replies(2): >>45132591 #>>45133301 #
50. pkolaczk ◴[] No.45132207[source]
Circuits as black boxes is usually a very leaky abstraction, because how circuits work depends a lot on what’s connected to them. And they have plenty of attributes that can interact in very weird ways.
51. ahartmetz ◴[] No.45132296{3}[source]
Teaching solutions without even mentioning the problems, basically. I hate it.
52. lll-o-lll ◴[] No.45132403{4}[source]
Absolutely the worst control systems of all time have been written by software engineers that don’t understand control theory. The second worst control systems are designed by those who only know the PID heuristic, and can’t be bothered to model a little non-linearity from motor drives saturating.
replies(1): >>45137232 #
53. lll-o-lll ◴[] No.45132591{5}[source]
PID is standard in the industry, but the reality is it is infinitely easier to model in the discrete domain. The z-plane if math, but you don’t really need much math. Just model like a games developer. Simulate with a bit of JS or python. Add the motor saturation! Play with feedback and disturbances.

I just think this gives much better results. The model can be as simple or complex as you need, and we aren’t trapped in the linear response range. PID is good enough for many tasks, but it’s never good.

54. foobarchu ◴[] No.45132815{4}[source]
This reminds me a lot of the car analogy that gets used to (poorly) teach object oriented programming.
55. dreamcompiler ◴[] No.45133238{4}[source]
There's Boolean algebra but no control theory is needed for logic design.

One minor caveat is that most CPUs nowadays contain phase-locked loop (PLL) clock multipliers. Those fall into the domain of control theory but strictly speaking they're not part of the logic.

replies(1): >>45137975 #
56. dreamcompiler ◴[] No.45133267{3}[source]
Agreed on the Laplace transforms. They instantly turn linear differential equations into basic high school algebra problems. But they don't work for nonlinear problems.
replies(1): >>45134327 #
57. dreamcompiler ◴[] No.45133301{5}[source]
Yes, but...

If you can model your problem with linear differential equations then control theory replaces the need for tuning. The coefficients you need just pop directly out of the analysis.

replies(1): >>45133698 #
58. wetwater ◴[] No.45133587{4}[source]
Its interestine, when you say abstractions. Could you explain what you mean by abstractions in this context and what do you mean by the underlying fundamentals.
replies(1): >>45137388 #
59. antod ◴[] No.45133630{3}[source]
Heh, I used electrical circuit analogies when learning hydraulics for pipe networks in Civil Engineering. I struggled much less than the other students who didn't know any basic electrical stuff from physics classes.
60. Karrot_Kream ◴[] No.45133698{6}[source]
Maybe I should add more context. I have specifically tried applying PID style feedback systems to computational problems, not controllers that interface with hardware, circuits, etc. My undergrad was in math and electrical engineering, I "pivoted" to software as a grad student (though I was always very involved in the software side of my department; I was a coder from when I was a kid.) The place I found it to work the best is with designing a homegrown autoscaler years before k8s ever became a viable thing for a company to play with [1]. Most of the problem domains I applied it to do not have linear models that can effectively model the theory. Yes I know that a PID is only proven to be stable when working with linear systems, but this is the reality of the problems I've worked with.

Eventually when if statements stop working I found that decision trees work great and XGBoost continues to be a great iteration of a decision tree.

[1]: I was an early hire at a tech unicorn and we built an autoscaler pretty early into the company's tenure. While it was a great success for a long time once k8s became established in the industry we had a really hard time training new talent to it and I left as we began a massive company-wide effort to move our workloads onto k8s.

61. antod ◴[] No.45133778{4}[source]
Yeah. As I mentioned in another comment, as someone who studied Civil Engineering (ages ago) maybe most EEs never learn enough hydraulics to know the analogy probably goes further than they realize - ie much further than just kids level stuff.

Voltage drops across components or look a like head drops across pipe fittings. Losses along a pipe are similar to wires. Head and flow rate are very similar to voltage and current across multiple paths. Kirchoff can apply to both etc.

Many of the quantities have direct parallels and derive from each other in similar ways.

Obviously there are limits. But my middling DC circuit knowledge helped a lot when learning hydraulics from a mathematical engineering perspective.

62. harrall ◴[] No.45134327{4}[source]
I remember when I first learned calculus and holy shit that was cool already. Then it kept getting better and better as I learned differential equations, linear algebra, etc.

To me EE = heavy math and that’s what makes it so fun.

I actually do software now but it’s completely different. There’s like no math in most applications of it. Putting something together with a Rasp Pi or Arduino feels like 98% software and 2% EE.

63. rramadass ◴[] No.45134974{5}[source]
Can you recommend some good resources (books/videos/etc.) for studying RF Engineering and doing RF Research by oneself?

Assume beginner knowledge of relevant mathematics/electronics and good software skills.

Am interested in both the practical side (eg. build a SDR from components) and the theoretical side i.e. the Physics/Mathematics to explain it.

64. imtringued ◴[] No.45137232{5}[source]
The biggest problem with PID control is that the integral term performs double duty as both a signal that accumulates small errors to minimize the steady state error, but also as a signal that shows deviation from the target due to unmodeled constraints.

It should be pretty obvious that you cannot overcome constraints by moving even harder in the direction of the constraint, which is what the integral term does.

65. imtringued ◴[] No.45137257{4}[source]
Why is bottom up or top down needed? Why can't you just explain everything at a high level first and then get into the details?
66. carlmr ◴[] No.45137388{5}[source]
One example would be resonant circuits. Ok great you can build resonant circuits, but what for? The fundamentals to understand frequency responses came later in signals and systems. The application came much later when I learned about electric motors, which basically behave like low pass filters (resonant circuits) which enables us to use PWM to generate sine shaped current curves by switching the input voltage on and off. The voltage signal is smoothed by the LPF circuit that is the motors windings.

I think it would have helped me if we talked about the motor or other examples first, and then did some math to show how the resonant behavior can be useful.

replies(1): >>45146544 #
67. uxp100 ◴[] No.45137975{5}[source]
And in my inexpert experience, they are IP developed by the fab. So if you are doing CPU design work, you may need to understand PLLs well enough to read a datasheet, but you will not need to design a PLL.

I maybe had the most trouble just figuring out which instantiated PLL in the chip belonged to which PLL design, and where someone stuck the documentation in the giant repo. Especially since a hardware designer may think, oh we don’t need to update the docs, “nothing changed,” but the PLLs did change names because of a process change and their parameters may have changed slightly, even if they’re essentially the same. And chasing down small changes and documenting them ends up being a lot of the job in software.

68. korse ◴[] No.45143424{3}[source]
Don't forget, Faraday hated math.
69. sevensor ◴[] No.45146544{6}[source]
It’s crazy that VFDs work! You have to have a really good ground though, or you get arcing through the bearings.