Date: September 30, 2013
Title: Forced FCC Filtering
Presenters: Chris Gammell, Chris Gammell’s Analog Life and Dave Jones, EEV Blog
Guest: Henry Ott, Henry Ott Consultants
Episode link: https://theamphour.com/165-an-interview-with-henry-ott-forced-fcc-filtering/
Source file: http://traffic.libsyn.com/theamphour/TheAmpHour-165-ForcedFCCFiltering.mp3
Dave: Welcome to the Amp Hour I’m Dave Jones from the EEV blog.
Chris: And I’m Chris Gammell of Contextual Electronics.
Henry: And I’m Henry Ott of Henry Ott Consultants.
Dave: And you nailed that intro Henry! Well done, most of our guests goof it up in some way. Thank you very much for coming on our show!
Chris:One of the legendary consultants of the world of EMC and noise and everything else.
Henry: I don’t know about that but I’m there, I’ve been around a while.
Dave: So can you actually tell us where you’re from and what you are doing these days and then … go back into your deep dark mysterious past?
Henry: Ok well I’m located in New Jersey, my business is pretty much all over the country – mostly the US and a little bit in Canada. I limit myself, I don’t go overseas anymore, no sense in travelling all those distances so I kind of limit myself to the US and Canada as I say. We do a lot of EMC training and consulting. Probably the biggest thing I do is training classes for individual companies at their location and about twice a year we try and do a public EMC class available to anybody. Usually one in the east coast, one in the west coast. Just last week we had one in Detroit and the rest of my time I spend consulting. That kind of keeps me out of trouble and keeps me busy.
Dave: You mentioned Detroit there, we’ve talked about a lot of the demise of the industry on the show. How is the Detroit electronics industry out of curiosity?
Henry: You know, that’s a good point. We scheduled it in Detroit shortly before the city announced the city went bankrupt, good timing right? It wasn’t actually Detroit it was outside Dearborn ok. I think the auto industry is coming back pretty much in that area, in the Michigan area let’s put it that way. When we do the public classes we maybe get a third of the people from local areas and the rest is from all over the country. 0:02:52.2
Dave: Oh right they all fly in to…
Henry: Yeah as a matter of fact we had one fella from Sweden even. Often we have some from Canada, we had 2 from Alberta from the west of Canada so quite often we have 2 or 3, or 3 or 4 of fifty people from outside the US. It’s not just local. I think things are a lot better in that area with the auto industry coming back, probably two years ago things were not very good.
Right is it just you in this consultancy or do you have a small group of people. Well right at the moment it’s myself. I have an assistant that kind of runs the office and takes care of things for me when I’m gone, answering the phone, making arrangements and doing things. Back a few years I had another engineer working with me on it too, he worked for me for about 5 years on it but he got tired of travelling that makes it difficult in this business.
Chris: Yeah definitely.
Chris: What does the public course entail? You said it was a week long, does it just run through the gamut of here’s EMC, here’s how you design around it, prepare for that kind of thing. What does a course like that involve?
Henry: Ok, it’s actually a 3-day class. I said it’s a week but I travel a day before come back the day after, so it’s a week of my time. It’s a 3-day class, it’s pretty much a general overview of EMC. We cover such things as grounding cabling, shielding. Digital layout and grounding, high speed digital decoupling, big signal PCB layouts, common mode filtering, conducted emission, RF and transient immunity. We cover pretty much gamut of different subjects, trying to make the broadest appeal. I also do a lot of one-day classes where we just spend all day on one subject, we might talk about shielding all day or mixing a layout all day, going into more depth. Usually the public courses I do as a general class with a bunch of different subjects. 0:05:20.7
Dave: How have the classes changed over the many decades you’ve been doing this? We’re getting insanely high-speed digital stuff these days, which wasn’t around, really you know 20-30 years ago in terms of digital. It was all RF – now we’re getting digital operating the RF speeds, how has that changed the game?
Henry: Well digital seems to be the big thing even today and we’re getting into more RF issues but I tend to emphasize digital in the class although a lot of the grounding, cabling, shielding is pretty much analog, or pretty much analog digital RF, whatever you want to talk about. I pretty much I cover stuff in all industries, even though as I said we held it in the Detroit area, it really wasn’t emphasizing the automotive necessarily at all.
Chris: It’s all analog at that point right? It’s a digital backdrop but my inner analog guy is shouting ‘no it’s all analog!’
Henry: Well my background is analog, when I started getting into the industry digital didn’t even exist in light of what we know today. My background is really analog, in college I specialized in feedback control systems, which are low frequency analog circuits and kind of got into business with analog frequency interference problems. That suddenly got me knowing something about noise and interference.
Chris: Yeah that’s great.
Dave: And that’s a great segway into when you got started because you were born in , if I may say, 1936 it says in your book.
Henry: Did I put that in the book!?
Chris: We can bleep it, we can bleep… 0:07:22.6
Henry: I think you did some investigation there or something…
Chris:Dave’s a snoop yeah.
Henry: It’s kind of interesting how I got into EMC, pretty much in a general sense the way most people that have been in it a long time , it was an accident ok. It wasn’t any grandiose idea of doing this but I was design engineer at A&TT Bell Labs working on telecom stuff, basically audio frequency analog type stuff.
Dave: And what year was this?
Henry: What year? Well let me go back a step further, I got out of undergraduate school I went into the air force for 3 years and then I worked for Bell Labs so we’re talking about 1960 when I started working for Bell Labs.
Chris: Which is kind of the hey day? 50’s, 60’s was kind of the really big time
Henry: Well you’re right the 50’s 60’s 70’s yeah you’re absolutely right. I look back …the 60’s is just when transistors and solid-state devices were coming into popular usage. My undergraduate school we only studied vacuum tubes we studied nothing about solid state physics, now I went in the air force between undergraduate and graduate school and in graduate school we studied solid state physics. I kinda feel that I’ve been in this business all through the solid state industry from crude to discrete transistors to integrated circuits to large scale integration etc. I agree with you the 50, 60s, 70s and into the early 80s was the heyday of that industry. 0:09:28.2
Dave: Is that because it was driven by the money from money from the cold war? Bell Labs did a lot of military stuff right? That was lot of the reason for the innovation. And then there was the space program of course.
Henry: Well that came along yeah in the 60s I guess, well mid 60s.
Chris: Mid 60s actually.
Henry: It was later than that I guess..
Dave: No they landed in 69 come on Chris.
Henry: It just seemed to be the heyday of learning things about technology and electronics. I guess if I look back it was the solid-state age. It was the development of solid-state electronics that made space for all of the developments that went on those days.
Dave: And would you go back to those days or do you think technology these days is just so incredible that you would never want to go back to the good old days.
Henry: Well I guess we all look back and say they were the good old days, the young people today will look back on their days and say they were the good old days so I think there is something in every generation that’s the good old days. I can talk about mine but that doesn’t mean …I’m sure there were ones before that and there will be ones after that you know.
Chris: I always think about it from the perspective of learning that kind of stuff as well. I think about the resources that are out there today with the internet and being able to access the information. I’m continually impressed with looking at older texts and even looking from a perspective of accessibility to computing machines of calculators and stuff like that. That’s what blows my mind is the fundamentals have to be so much stronger, whereas today, I muddle through most of the time I don’t know about you Dave but…
Dave: After 20-30 years I’m still muddling through.
Henry: You know what I think that was also the age of a lot of these large industries like Bell Labs, IBM, RCA had big research labs and privately funded, just were developing an awful lot of stuff. There’s been a bunch of articles in magazines where have all the big research labs gone – which have pretty much all gone today. If it doesn’t apply directly to a product nobody wants to work on it these days. Not in the area I was in but we had large numbers of people working on something that had no end product that was obvious. Sooner or later something probably came out of it.0:12:20.5
Dave: And how did they decide to work on those things did you have the ability to work on anything, like you woke up and had this brilliant new idea were you allowed to work on it? How did the culture work in Bell Labs?
Henry: I think there was part of Bell Labs where that was true in the research. I was more in the development side of Bell Labs, in the basic research they could do somewhat of what you were saying ok. The culture there was wonderful as far as driving innovation, everybody talked to everybody, you could go into any bodies office. One culture that Bell Labs had developed that was different from most companies at the time was other companies separated their electrical people, their mechanical people and these people. Bell Labs intentionally mingled them all together so you would talk over a cup of coffee and somebody doing something completely different would be down the hall from you and this stuff would all get mixed up and come up with ideas that nobody had thought of you know. 0:13:26.5
Chris: That’s great, that’s one of my favorite things, obviously it’s later, but in the book Bill and Dave about HP culture which is an outcropping of Bell Labs, it’s the same kind of thing of the coffee break time 10am the bell goes off there’s the beer bus and the end of the week. These days it’s all cube based and it’s like – alright do you work, go home, whatever no big deal. Not all companies are all like that but I feel like that’s common these days.
Henry: There’s a good book out there on the history of Bell Labs I read a year or so ago it’s called the Idea Factory. It’s a cute title.
Chris: Oh ok, we will try and link that one in.
Chris: Yeah that’s a good one.
Henry: Yeah the Idea factory. It’s hidden somewhere in my office under something at the moment. It’s an interesting thing that goes through the development at Bells Labs I enjoyed reading it because half of it I knew being there and about half I didn’t know because you never know everything that’s going on obviously.
Chris: Right especially with the size of Bell Labs.
Henry: Yeah the multiplicity of locations etc. so it was a big thing.
Dave: At a big company like that how did you keep in contact internally in the company? Now there’s company email, intranets all sorts of things like that. Pre internet and pre communications revolution, how did you know what everyone was doing internally? Did you publish internal documents and hand them around I mean you didn’t even have photocopiers back then right?
Henry: Are you asking me was there life before email? is that the ….
Dave: Yes …well even life before photocopiers. Even before email you would pass things around the company, photocopy it and go read this.
Henry: Obviously not as well as things go today. Everybody wrote everything up as memos and everything was available but a lot of the interaction was as I said just personal, running into people and talking with people over lunch informally. 0:15:37.6
Chris: That sounds better.
Henry: To some extend that a better way than all these doggone emails ?
Dave: All the new-fangled yeah …I think it could be. Maybe not as efficient…
Henry: I was going to say, yes not as efficient but… If you really know what you want to communicate no, but as far as not knowing what it is you want to communicate or talk about then the answer is yes. Over a cup of coffee just talk about who knows what and come up with something. You’re not going to normally write an email unless you’ve got something in mind that you want to say, sometimes just a discussion. But, I still didn’t answer the question about how I got started. We kind of got distracted.
So I was a design engineer back there and I got involved in couple projects involving low level sensitive electronics in a noisy environment, a lot of electro mechanical stuff going on, big motors and breaks and a lot of noise. First thing I learned is I know how to design, what I was supposed to do was electrical engineer but I had no idea how to control the noise, cause that was never taught in school and still seldom is, although there are a few universities that do.
I looked in the library there’s a little bit of information but not much so I kind of had to figure out how to overcome these problems just to do my job and suddenly I knew a little bit about noise and interference than anybody else and that kind of makes you the expert, you know. That was kind the gist of it and suddenly everybody started to come to me because well Henry knows a little bit about that you know. I didn’t know everything about it but I knew little bit about it. Everybody wanted to get into digital at that time because that was the new thing and I was never one to follow the crowd. So I said, you know I like this idea about noise and interference stuff and so I kind of leaned more to getting more and more involved in that. 0:17:53.9
Dave: That was with inside Bell Labs?
Henry: Yes that was inside Bell Labs yeah.
Dave: And how long did you spend at Bell Labs all up?
Henry: I spent 30 years there.
Dave: Wow! And then after Bell Labs?
Henry: Another couple of years and I’ll be thirty years doing my own consulting. So I’ll have had 2 30-year careers and that’s probably enough.
Dave: & Chris Wow
Henry: What I did in Bell Labs which I think is interesting… Bell Labs was big on continual education, they ran their own education programs and they thought it was good that everybody could learn as much as they could or wanted to and in almost any subject by the way.
So I went to the fella who was in charge of the in house education program and said ‘you know we need a course or class on noise and interference’, for lack of a better phrase. Because engineers know how to do what they are supposed to do, design amplifiers, oscillators, in those days things like that, even digital but nobodies learned anything about noise and digital interference. So he said ‘that’s a good idea I’ll look into it’.
Six months went by and I never heard from him and I thought well he’s forgotten about it and six months later he called me up and says ‘remember you were down here in my office and you were talking about this noise and interference stuff?’ and I said ‘well, yeah ok’. He said ‘well I checked all our resources and nobody knows anything about it so …..’
Resources were basically two fold – they would go to the universities and get professors to come in and talk about some subject. Then Bell Labs engineers especially were telecom related and of course neither of those knew much about this subject so being a kind of young naive engineer I said ‘well then I’ll teach one’.
Henry: And they got me into doing this stuff and after about 5 years of teaching it I had a big set of notes and I said ‘well maybe this would make a book’ and I came out with my first book ‘Noise Reduction Techniques in Electronic Systems’ back in 1976 as a result of that. 0:20:13.8
Chris: Right a classic.
Dave: Right that was the first edition, how did you write the book back then? Did you do it on typewriter?
Dave: I’m fascinated by how people did it back in the old days.
Henry: The first edition was ‘76 and the 2nd was ‘88. The first edition was written by hand on paper and went to a typing pool and was typed up.
Dave: Typing pool right
Henry: That’s a silly word today right? Exactly yeah. The 2nd edition was done on a computer but not obviously personal. We had terminals on our desk with one main computer at the company.
Dave: Right mainframe business.
Henry: The ‘88 second edition was done that way but the first was hand written.
Dave: What about any diagrams in it, I don’t have the first edition did the first edition have diagrams and schematics? They were hand drawn as well and reproduced in the book photo typeset?
Henry: Our art department did most of the drawings , the Bell Labs art department. It was virtually all analog. The first edition had about 2 paragraphs on digital.
CG: Oh that’s interesting what just because of the timing of it right? ’76 ..
Henry: The second edition had 2 chapters on digital and now my present book is now half on digital so interesting how times have changed there. But you know some very fundamental things like shielding and grounding are things that are the same for analog or digital just the frequency components are different. One advantage I had is that a lot of the things in the book were very basic and they last even if technology changes even if maybe some of the applications weren’t very realistic at that point.
CG: So that was actually published through Bell Labs, that was another component of the learning program there? How does that work?
Henry: It was published by Wiley, John Wiley and Sons. Bells Labs was very encouraging, you want to write a book go right ahead. They had to approve the manuscript you know. You weren’t giving away any secrets or anything you know.
Dave: So this was 1988 – is there any ideas about a third edition? Is it needed?
Henry: The second edition in 1988 came out right after I left Bell Labs, but I wrote it while I was at Bell Labs.
Dave: So the copyright that’s why it’s got copyright Bells Labs
Henry: The copyright says Bell Labs on it yeah. I started a third edition of it and that turned out to be my new book Electromagnetic Compatibility Engineering.
Dave: Oh ok
Henry: The newest one 2009 I had completely rewritten almost all but three of the original chapters and I added six more chapters to the book and it was a completely different book in my mind so we renamed it. It’s almost a 900 page book.
Dave: So are the two book different? People should get both? They are actually complimentary?
Henry: No, because you really don’t need both. The new one pretty much includes everything that was in the old one plus a lot more implicit up to date stuff. it started out as the third edition but then the way things changed…
I look at it the Noise reduction techniques and Electronic Systems was my experiences at Bell Labs and Electromagnetic Compatibility Engineering is my experiences after Bell Labs, after I had left there.
Dave: Any you’ve got a quote in the second edition “Everything should be made as simple as possible but no simpler’ – Albert Einstein.
Henry: That’s from albert Einstein.
Dave: Yes. Why did you decide to put that in? In what way …
Henry: That’s in all 3 books. Well you know, a lot of people writing books on cabling and shielding were writing with a lot of theory and very complicated and my approach was to try and simplify it.
CG: We liked that.
Henry: I wanted to be able to understand it as the design engineer myself. So that’s been part of my success I think. I wrote all of the books, and this is the honest truth, for me to understand and read. Most design engineers appreciate that so I thought kind of what I did was try and make a complicated subject simple so I put that quote in.
Dave: Got it. So you don’t really need all that complicated field theory to do practical EMC stuff? Are there any cases where you do need to get deep into the theory of it?
Henry: First of all you’re right – you don’t need all of that. You need a little bit of theory if you want it to be more than a cookbook. 0:25:48.1
Henry: And that’s kind of what I tried to do. I don’t think very much in the EMC business you need much of that theory at all. It’s good to know some of that because it may lead you in certain directions etc. The reason you got there might have been through some complicated theory but once you get there and understand that you can simplify it.
Dave: That applies to most aspects to most aspects of electronics engineering not just yeah. That’s why ‘the Art of Electronics’ book is so popular because they deliberately don’t include any of the heavy math. I don’t think you’ll find a single integral in the whole book. I think that’s the reason for their success. Otherwise it’s a book for teaching – it’s not a book for the practical engineer.
Henry: Well if you think about it who writes most of the technical books? Often Universities. They are writing more the theoretical and you don’t get as many practicing engineers – at least back in those days you didn’t – actually writing the books. I think they do their job and they go off on….If I hadn’t taught it I probably wouldn’t have written a book. I had a whole set of notes and thought this is probably useful for something and maybe we could turn it into a book.
Chris: As you were developing these notes how did you go through and start digging into this stuff? Because some of your stuff in this book and your technical articles on your site they’re awesome, because that’s the practical stuff I use all the time like the mixed signal layout stuff. Where do you connect ground plans underneath abcs, doing that kind of stuff. There’s so much conflicting information and there’s so much just information out there, how did you develop that course?
Henry: Especially on that mixed signal one is a good example and it’s a whole chapter in the new book on mixed signal. All of a sudden I seemed to get a bunch of consulting jobs with people with mixed signal problems you know? There was always some and then it seemed to come together all at once I got 3 or 4 in a row and I think my experience is often the problem of the year. Everybody seems to have this problem this year and that problem next year and I realized there was not a lot of good information.
I wrote little write up on my webpage about and I got a call maybe 6-7 months later. An editor from Printed Circuit Design magazine, he said I saw this thing on mixed signal on you webpage. Would you be willing to expand that into an article on Printed Circuit Design? That was a good excuse to work on that more. So I did that I wrote a little 4 page article July 2001 Printed Circuit Design Magazine. From that I developed a course from it, so it kind of just went on and on and on you know. I think a lot of the things were like that because of problems I ran across in my consulting business. Some of the problems I didn’t know the answers to and then I kind of worked on them or I developed better answers to them.
Chris: Yeah maybe your fourth book you shouldn’t quote Einstein you should quote Nothing is as powerful as an idea whose idea has come – except you modify it. “Nothing is as powerful as someone who wants to pay you to solve their problem” right?
Henry: I wasn’t smart enough to say that though or do that at that point.
Dave: Do you have any idea how many copies of the book have been sold?
Henry: Yeah. You know a lot of technical books like that especially if they are not standard university texts like basic physics don’t sell large quantities at least like popular books fiction or something. The first 2 editions – I’ve done well selling those books for the market they are in. The first 2 editions of noise reduction techniques probably combined sold 60-70,000 copies.
Dave: Wow Nice… That’s good for a technical book.
Henry: The new one EMC just came out in 2009, that’s probably 5-6000 copies total at the moment. I expect it to get better in the long run. 0:31:12.9
Dave: Got it. As you said it really needs to be integrated as part of a some basic course and things like that cause that’s how most people get these books. It’s the textbook they got during their course on that particular subjects.
Henry: There are a couple of universities and colleges that are beginning to teach it as part of an graduate or undergraduate, usually it’s a senior elective or something. The University of Michigan in Dearborn is one of them.
I’m gonna start putting some stuff on my web page about that for people that … so colleges or universities or even other consultants as well as myself are using the book for teaching EMC as a resource if somebody is looking for an education there. I hope that’s something we are going to work on adding to the webpage.
While I’m on the subject of books I’d like if you’ve got a second here … right now there’s a lot of EMC books on the market and I get this listed on my webpage too. I got what I call my 3 book EMC library. You can buy a lot of books and there’s something good about every book, some people cover some things better than others, but obviously there’s a lot of overlap if they are all on the same subject.
I got three book that if you buy them on the subject of Electromagnetic Compatibility Engineering and single integrity it covers the subject from DC light frequency wise and there’s very little overlap and they are all very easy to ready and I think that’s a big advantage. If you want to limit yourself to just 3 books I give you a recommendation, my Electromagnetic Compatibility Engineering would be the basic book, then there’s a book called High Speed Digital Design by Johnson and Graham
Chris: Is that Dr Howard Johnson?
Dave: Yes it is, you’re familiar with him. I know him very well.
Dave: We’ve had him on the show as you are, he’s been on the who talking abou this book.
Henry: Oh ok fine, he’s the single integrity guy up in Spokane Washington area. Him and Dr Marty Graham, I know Marty Graham very well – retired now from Berkeley University in Ca. I consider that a crossover book, it’s kind of a lot of EMC issues and beginning to talk about some single integrity issues. It’s got a bunch of interesting measurements that’s not in another book and it’s also easy to read so… All the books I’ve got other than my own, I use that book the most and then there’s a third one if you are interested in the real high frequency stuff single integrity as things are getting more and more today, with almost the same title it’s called High Speed Digital System Design, the word system is in there and it’s by three authors, Hall, Hall and McCall.
0:34:37.5 Inaudible. Overspeaking.
Henry: A lot of single integrity books are very theoretical but this is a very readable book and I loved the first sentence of the book and I wished I’d thought of it. Out of a clear blue sky, the first sentence of the book says ‘the speed of light is just too slow’.
Chris: That’s great
Henry: It really sets up the thing about what the book is about. Those three books cover an awful lot without overlapping a lot, there’s a lot of other stuff you can get but …
Dave: Are you still doing research into the subject these days? Is there always more to learn? Do you build stuff and measure things?
Henry: Do I? You know my research is mostly in doing consulting and sometimes I’ll get an interesting problem that I’ll work on the side, you know kind of develop some other ways to do it but …not really a lot you know between doing the training, classes and consulting that pretty much keeps me busy.
Dave: Got it
Henry: When I got a little hour free or something you guys wanna talk to me.
Chris: We appreciate it laughter.
Dave: You’re a busy man.
Henry: I think you gotta keep into the consulting business that keeps me down to the real world of what’s going on. If I just wrote books, you kind of miss what’s going on in the real world. That kind of drives where … like the mixed signal as I had a couple of consulting jobs with problems that got me to write the stuff on mixed signal etc. Had I not had that I probably would never have written the stuff specifically on mixed signal.
Chris: We have some questions from the audience that we should include.
Henry: Ok I’ll try and give them a shot.
Chris: So big question I always have as well, FEWS on the forum wrote about. He was wondering about recommendations on shielding and shielding cans and specifically… He heard that they can cause resonant cavities when soldered under ground planes, is this true or a myth? Then there’s a whole bunch of other questions. Then having to double as heat sinks … well let’s start with that first one perhaps. 0:37:18.4
Henry: Can it be a resonant cavity? Sure any shielded box can be a resonant cavity. So what? It still serves a purpose and … almost everything has a plus and a minus to it and that’s one example but that doesn’t mean not using them… I would not think about stopping using them or anything.
Dave: You just have to be careful and you have to know about them.
Henry: Yeah that’s important thing to know. I know when I talk about grounding … grounding is a very complicated thing and I don’t want to get into it here….. I always make the point grounding is a compromise. Every ground system that you and I have designed has faults.
Chris: It’s got to go somewhere right?
Henry: It has advantages .. the name of the game is trying to balance the advantages against the faults for the application. I know some people would argue with you and say that this type of ground has got this fault and this fault and I’d say ‘yeah but give me a better choice for the application’ and they don’t have it.
Henry: But it’s important as you say to at least to understand the faults and the limitations and as part of your design and testing to make sure it’s not hurting you.
Dave: That’s right, because when you finally test your product and you getting some unusual problem on there like there’s resonant cavities, it’s oscillating it’s frequency and you’re getting a weird you know test your thing sweep it over frequency and you’re getting whoah what happened there at 2 Ghz..
Henry: You get something like that so maybe you gotta put something inside your can to break up the resonance or something like that but still serving the job of acting as a shield yeah
Dave: But you’ve got to know that it could be caused by the resonant cavity effect otherwise you might think ooh is there a 2 ghz transmitter around here somewhere
Henry: Well you’re right, that’s why I always say you want to know the negatives as well as the positives to whatever you are doing.
Chris: I had a co worker talking to me – I mentioned you were going to be on the show today and we were just talking about EMI testing and being in anechoic chambers and stuff like that and just sometimes you put a piece of copper tape somewhere and it fixes one problem and the noise screams out another side.
Henry: That’s absolutely true, you know you push in here on the balloon it pops out over there.
Henry: That doesn’t mean you shouldn’t fix this problem, then you can fix the other one.
CG: Well your boss is going at you one day ….You gotta make him happy that day and the next day he yells at you for something else ….
Dave: We’re in a boat and it’s leaking and there’s a 1000 holes and you’re trying to plug them all before it sinks….
Dave: Oh goodness..
Chris: So you said you primarily have development background, is that from the hands on practical approach? I could imagine that someone with a more theoretical background being like well lets go back to first principles and stuff like that was it because of the development background that you had?
Henry: I think so, as a teenager I’ve always been hands on building things and doing things. I got into engineering, my interest in theory is so that I can build something or make something not in for the theory itself. I come at it bottom up and some of the university people come at it from the top down you know. With the theory down I start from the practical up, you gotta know enough theory from the practical to know what you are doing.
Dave: Do you think they’re not teaching enough of that these days ? Are you getting a lot of young graduates in your courses?
Henry: We get everything from young to old and .. I think engineering education does have a problem today. You can get a Bachelors or Masters, even a PhD in some places without ever studying a field theory course or anything like that. Especially in computer science where they just talk ones and zeros. I think, it’s hard to argue there’s so much to study, I’m not saying you shouldn’t do that but they are taking out a lot of the fundamental stuff I think because they are saying fewer and fewer people need it you know. 0:41:46.6
Dave: Right because there’s so many off the shelf solutions out there, we take it for granted that we can just go to Digikey and buy 200,000 chips that do everything that’s basically a module, a plug …
Henry: I kind of worked through this whole solid- state development. When I started working in solid-state we designed transistor circuits to a transistor, now it’s more like a system thing here everything is in a box called an IC and all you do is interconnect a bunch of boxes you know? You don’t necessarily know what’s going on at the device level.
Chris: See the only think that I think that’s different these days … see I think about your mixed signal article I’ve read 3 or 4 times in the past year at least. This is where the rubber really hits the road for me at least right, because I am just integrating these Ics and I am just connecting up these boxes but then it comes down to that point of well I know ground loops are a thing.. I want to make sure I have that right and then you kind of get to that point and you start focusing on this problem and your whole world explodes because it goes from I have this simple chip it seems like to start with and if I step …
Henry: It suddenly becomes complicated. 0:43:05.4
Chris: Exactly, it opens up the entire world of ‘oh crud what the heck am I going to do about all the things that could go wrong’. The fall back of course is to go back to the vendor and be like – ‘do you have recommended designs?’ but then if you have to move outside of that then you have to …
Henry: You’re right and that’s the problem as I say. A lot of people aren’t learning the fundamentals today. Look at digital logic, the digital design there’s the 1 state and 0 state right. There are no EMC problems in the 1 state and none in the 0 state. All the EMC problems occur in the transition and the transition is an analog state that the digital designer thinks does not exist.
Dave: And it’s much higher frequency than your 1/0 rate… transition rate.
Henry: Right because digital designers are RF designers and don’t know it.
CG: Well the good ones are.
Henry: The good RF designers know what they are doing, they are doing RF and they understand it, but the digital people don’t think they are doing that.
Chris: Yeah I have a firmware guy I work with and he’s ‘oh we hit a problem lets pull out the logic analyzer’ and I’m like ‘yeah that works when you need to know what word you have when the signal’s clean. There’s a whole lot of other stuff going on ….’
Dave: Lets get the oscilloscope instead of the logic analyzer.
Henry: Doesn’t help you much with noise interference or EMC.
Chris: Do you have go to tools? We always like talking about test gear and stuff like that on here. Do you have go to tools that you recommend to people that are maybe starting out.
Henry: Like software tools?
Chris: Oh no I mean like hardware tools, like specific scope types for chasing down EMC problems.
Henry: Yeah some small probes, little magnetic loop probe to probe.. we use a communal current probe that goes on cables to measure the unbalanced current on the cable that causes them to radiate.
Dave: Almost nobody would have one of those in the lab. That’s one of the problems. That’s the problem right. It’s not general purpose kit? Should it be? Should the scope manufacturers actually be providing one of those?
Henry: Yeah and people don’t know what to measure if they were to measure from an EMC point of view.
Henry: Cause the other thing is, those two probes and the spectrum analyzer engineers often don’t know how to use a spectrum analyzer. You learn using the oscilloscope in school and the volt meter.
Chris: Yeah right.
Henry: The spectrum analyzer is a complete other beast
Chris: I muddle through with you know like a lot of the new scopes have FFTs on them. That’s kind of the best I can do with you know …see some frequency content … do what I can.
Henry: I used to always say that the big problem price wise here is spectrum analyzers but we now have some really good ones that are very inexpensive.
Dave: Yeah they are down to 1400 dollars or something. Well you can get a, one I often mention to people is a Riegold.
Dave: Is it a Riegold 815. Yeah Yeah I’ve got one of those here in the lab it’s only 1400 including tracking generator.
Henry: Yeah and that’s a well built thing, works very well got a good frequency response. It’s not a cheap spectrum analyzer it’s an inexpensive analyzer. There’s a difference right. It’s well built, there’s no excuse because a scope costs more than that today. A decent scope, at least as much as that so people …..
One of the one day classes I do is on a thing called workbench EMC measurements. Measurements that you make in your lab that relate to EMC. A lot of people are interested in that because like I say they don’t do these things … they don’t know what to do. 0:47:30.4
Henry: They don’t know what they are looking for or what equipment to use. There’s a whole chapter in my new book on pre compliance EMC measurements – all done with simple equipment.
Dave: Yeah that’s a big thing these days cause you want to ensure that your design is at least in the ball park before you go and spend 10s of 1000s of dollars getting it compliance test.
Henry: That’s correct but you know how many people don’t do that they go and spend $10,000 and go … clarify* in detail. And quite often they fail so bad that you could have found out in minutes if you just did a couple quick tests yourself.
Chris: So you’re saying that your book is going to save people $10,000? I say that right there should be your sticker on the front. 0:48:15.4
Henry: You read that one chapter. 0:48:18.8
Dave: Is there any really common mistake that people make at that EMC, that causes them to fail EMC compliance.
Henry: Sure – there’s about 10 different things, let me just give you a couple. By the way I have an appendix in that new book. I was going to put the 10 most common EMC problems but kind of sounds a dull subject. I wrote the appendix – the 10 best ways to maximize the emission from your product. Do this do that do the other thing.
Chris: That’s great.
Henry: Now the books been out since what 2009, 4 years now and I got one email now just the other day from a guy says – ‘I was reading that appendix – aren’t we supposed to minimize the emissions?’ He doesn’t get it. The idea was to invert it and you know make it a little more interesting.
A lot of EMC people read it and think it’s great because they say there’s so much truth in that people do this and I kind of prefixed that in the beginning. I don’t think this appendix is needed because most people do this anyhow, so they don’t need me to tell them.
So let me give you a couple. Basically what I referred to was an interrupter return current path where you run traces across splits in planes. If the adjacent planes got a split in it, the return current should be right underneath the trace. See everybody thinks about the signal current but everybody forgets about the return current.
Chris: Oh yeah definitely
Henry: If it’s right under the trace it’s nice small loop that’s a good thing but if there’s split in that plane or slot in that plane there, that causes major problems ok. The second one would be terminating shielded cables improperly with long pigtails. Along with pigtails at all – it should be 360 degree termination.
Chris: Right Just those two things would make tremendous differences if people would realize and correct those things.
Dave: Traps for young players.
HO: Two good pieces of advice I think.
Chris: Yeah, do you visualize current like a train, like a bullet train? Cause that’s how I do it.. I think about where the currents going and where it doesn’t want – “ want” to go and if it runs into something it doesn’t like it’s going to be like ‘ no I’m going to start radiating like crazy cause it’s going to do everything it can to get across there…’
Henry: Well I don’t know that I looked at it like that but the net effect is the same.
Dave: The way I look at it is always loop area – how big is your loop? You always want to minimize …
Henry: That’s kind of what I do….I look at loop area. But see how many people look at the signal part of the trade and as long as there’s a ground symbol on both ends, they figure somehow it gets , they never give a microsecond of thought to where that return current is flowing. Somewhere in the ground right?
Chris: Yeah, I’ve seen people suggest that they actually draw individual ground returns for beginners especially, so that there’s a really clear concept of it’s not going into some ether and below your board – it’s going back – it’s gotta go back! HO: So many people think that ground is a one way thing and you can just dump current into it and it disappears and that’s not exactly true.
Dave: I’ve done a video on that where I use a current chasing probe and I chase the return current through a ground plane and you can show that look no current flows down this area here it’s all flowing there and people just go ‘oh wow I didn’t know that I had no idea.’
Henry: Yep, yep
Dave: The flip side for that’s like one of those wow moments for people … my latest video is measuring noise in op amps and the feedback is like ‘hmm who cares I don’t want to know about that stuff, go away give me something interesting!’ I find that a bit disappointing because I think it’s important to know about noise in op amps for example and the different types but a lot of people seem to think this is boring stuff unfortunately. How do we get them to be more excited by it? I guess they need to have been bitten right. They need to have a problem where… they have to be bitten on the bum.
Henry: I guess so, that’s an important issue, important point here. How do you get people to realize it’s important this whole subject.
Dave: I know – have you got any advice?
Chris: Maybe we can open that up to the comment section ….
Henry: A good friend of mine Dr Clayton Paul who taught at the university of Kentucky and Mercer University, just passed away last year a sad, sad thing but he was a real good EMC guy and a real good professor. He used to teach an EMC class and he had a real hard time getting students to attend the class because they didn’t think it was important, ya know? He said I gotta find a way to get them to attend the class. So he also had a basic circuits class he taught that had a lab associated with it. They’d build a little digital something as part of the la. He got the idea he said we’re going to build this little thing let’s say it’s a counter with a readout or something but instead of putting it on one board he put it on two boards with a meter long cable between them. 0:54:24.3
Henry: Everybody did that and they made it work and maybe the first thing they ever built they made work and they knew everything in the world and then he had arrangements with IBM in Lexington and he brought them over to the EMC lab and he measured the radiation from them and said you couldn’t sell this thing anywhere in the world. And you know after that his EMC class would fill up.
Chris: Ill bet
Henry: Now they relate that maybe this is something that I should learn about. You know a lot of engineers in the field don’t appreciate the importance of EMC, surely the students don’t. They haven’t got that level yet of understanding some of the other things yet, so EMC is the least of their concerns.
Chris: Personally I get away with a lot from being lower speed kind of stuff. That definitely helps. I think from the grace of, like I said before, app notes, having suggested layout, that kind of stuff that takes people a lot further than it used to right where maybe they weren’t as good as application departments but it’s just glossing over stuff. It’s still there, these things are determined at some point but it’s just either pulled into chips application departments or it pops out later once the engineer doesn’t realize it when they go EMI testing.
Henry: Yep, especially in the high frequency stuff.
Chris: Oh yeah, what about DC to DC stuff? We were just talking about loops and stuff like that, whenever I hear loops I immediately think of DC to DC control circuits…
Dave: Switching regulator
Chris: Switching regulator that kind of stuff.
Henry: DC DC converters, like I said, very noisy stuff and that produces a lot of conducted noise problems. I’ll tell you another thing right along those lines that pretty much behaves like that is coming into fashion is variable frequency motor drives.
Dave: Oh yes
Henry: Where they control the phases of … the speed of 3 phase ac motors electronically. Matter fact those motor drives are basically almost like DC and DC or AC to DC convertors but instead of producing a voltage as the output they produce a drive to the motor and they get all the switching noises so I see a lot of problems with that recently. And that’s the automotive industry too cause that’s where you have your drives on your electric car.
Dave: Oh really yeah that’s a big deal.
Henry: In fact in the beginning when people were talking electric cars I figured they got DC motors. They got 3 phases electric motors, 400 volt 3 phase electric motors. That’s a lot of ..
Dave: They are portable EMC generators!
Dave: Is there any industry emission requirements for those instead of exhaust emissions, EV car radiation standards.
Henry: There are.
Dave: Are the automotive industry actually going to have their own standards for that or is it just like the regular FCC requirement. Do you treat a car as a regular product?
Henry: Yeah car is regular product. There’s a lot of them around! It doesn’t come under FCC by the way. The European Union has their own requirements on it, the car manufacturers are required to meet and most of the car manufacturers have their own requirements. Interestingly enough as far as radiated emissions more stringent than the FCC. Why do they do it even more stringent? Well they got small space called a car and the antennae sticking up with an AM FM radio. When you buy a $20,000 car you expect your radio to work without noise and static. I don’t know why you have that crazy idea …. Simple thing is you cant listen to the radio comfortably, is a reason to downgrade that car.
Dave: Yeah of course
Henry: They put emission requirements on themselves that are 40db below the government’s.
Henry: Right because damn antennae is sitting right next to the microprocessor that’s in the car!
Chris: I’ve heard about new parts coming out actually where they tune the DC to DC to chase the am or FM tuner effectively so that it’s always a certain amount away from the switching … must have been am cause of the switching frequency but they chase that around so as your tune your radio it doesn’t pick that up which is brilliant.
Dave: Once again there’s a problem that’s solved by one of these chips and then you don’t understand it from the design point of view.
Henry: Automotive usually does a good job even on susceptibility because you drive your car maybe down tot he airport or by a building that’s got a big FM transmitter on the roof you may drive through a very strong field. You don’t want your engine to stall…
Dave: Or your air bags going off!
Henry: Or you don’t want your cruise control to go crazy.. so automotive has a lot .. originally started out as self imposed restrictions just because of what the product is… what the customers perception of what the product is and what they expect.
Dave: Is there a big difference in terms of traps for young players between conducted and radiation emissions? Which do you find more troublesome? Do more people have problems with radiated emissions or conducted? 1:00:50.1
Henry: Radiated. Conducted is mostly below 30 MHz, radiated is above. You know where the conducted is coming out. On the power line so you know it’s the filter.
Dave: Of course any cable coming out unless you’ve got a sealed box.
Henry: But radiated could be anywhere, radiated could be in multiple cables, radiated could be through the enclosure etc. so it’s a lot harder to control so most designs are the controls are conducted well. Clearly the radiated is more of a problem. Then there’s always somebody that’s got the opposite when you just look at all the problems in the world, radiated is more of problem.
Dave: Then there’s a lot of people who think I’ll just whack it in a shielded box and I’m done right?
Chris: They cage everything!
Dave: I think you’ve got an excellent graph somewhere in your book that demonstrates the different types of shielded materials and the frequencies they operate over if I remember that correctly. So you might think ok I’ve put it inside an aluminum box but that only works over a certain frequency range – is that right?
Henry: Well it’s mostly the apertures, the problem is the shielded box has got seams and apertures. Designing a good shielded box is not the simplest thing. And if you have taken the approach you just said you probably are not designing a good shielded box. Besides that, cables go in and out that bypass a shielded box.
Dave: That’s it, that’s it.
Henry: So you not only got a design a good shield but you have to filter all the cables. Ignoring proper design and just using a shielded box is not the optimum way of designing anything cost wise or anything else usually. But you’re right a lot of people say as a last resort will just put in a shielded box.
Dave: So what is the proper way to get a good shielded box do you solder all the complete seam around outside?
Henry: That would work fine but not very practical.
Dave: No that’s right
Henry: You gotta limit the maximum dimension of any seam or aperture cooling hole in order to limit the radiation through it. Especially in seams you’ve gotta have a conductive finish on the seams so when they push together they make contact etc. Designing a good shielded box is not a trivial job.
Dave: Right so you cant just get a die cast LO box and then just screw on the lid and think that you’re going to get performance from DC to daylight.
Chris: Nor just tin foil like I would do.
Henry: Well you know at high frequency the thickness of tin foil is fine it’s not really the thinness it’s just they end up making it a really good enclosure with no penetrations of it.
Dave: So you don’t really have to worry about radiated emissions below generally about 30 MHz you not going to get too many issues?
Henry: Well not regulatory wise. The regulation do radiated emission testing above 30 and conducted emissions below 30.
Dave: Got it.
Henry: Now there’s always exceptions to that.
Dave: Like AM radio in your car for example
Henry: Yeah right but the rationale for that is that most products are not big enough to be efficient antennae’s below 30mghz.
Chris: Ahh just because of wavelength that kind of thing.
Henry: So the radiation from them isn’t too much of a problem. However the ac power line they are connected is a big antennae. I cant very well measure the radiation of the power line and not pick up anybody else’s radiation so they are going to tell you how much you can excite the power line. That’s really the conducted emission test. The conducted emission test is really a radiated emission test in disguise. 1:04:56.8
Dave: Right, are there any common traps that people fall into in terms of mains powered products? Is it adequate just to put in one of those IEC mains input filters there and be done with it, wipe your hands and go ah that should be enough.
Henry: Well if you mount it properly and ground it properly and it’s a good designed filter it might be – there’s a lot of times you can get away with doing that. You know what I find mostly with filters is power line filters, is they are not mounted well and they got too much parasitic impedance.
Dave: Oh in terms of the connection of the metal case of the filter …
Henry: Referring to the metal box of the filter to the chassis or I’ve seen people take the power lead into the filter and the power lead out of the filter and wrap them together. So you couple the all the energy around the filter basically ..
Dave: Exactly you’ve just got capacitive coupling right there.
Henry: It looks nice, it looks nice married like that.
Chris: You get the sticker too right?
Henry: I would say interesting on power line filters, an interesting subject I would ay 90% of the times I fixed a conducted emission problem with a filter, it’s mechanically not electrically, it’s the mounting or the wiring.
Dave: The physical wiring and people forget about the capacitive couple in between the wires when they tie them all together. It just sneaks right past the filter it just bypasses it.
Henry: Unless you had a really noisy product and you buy a commercial power line filter, the power line manufacturers have got those filters down pretty damn good.
Henry: If you implement them properly and use them properly. You can almost do as you said just put them in a forget them. But it’s so easy not to put them in right and mount them right so it doesn’t actually always work out that way all the time.
Dave: How many people actually come to you screaming ‘help my product doesn’t work!’ Is that the majority of your business?
Chris: Yeah I was wondering about that to…
Henry: Well no I’ll tell you why , there’s a lot of people that do that .. we do a lot of training classes what that means is I’ve often got a lot of commitments next week or the week after – like next week I’m going be in Tucson doing a class for somebody. Last week I was in the Detroit area. So if somebody wants it fixed next week I say I cant do it – you know because I got other commitments. If it’s real quick emergency I usually don’t end up doing it because my schedule is such that I can’t … besides I’m not crazy about those kind of crisis problems.
Dave: Right Yeah yeah.
Henry: Although I work with people fixing things after the fact usually when they are in as much of a hurry but the ideal thing is working before the fact. Coming up with something new and lets kind of try and do it right to begin with.
Dave: Do you charge like an idiot tax?
Dave: They have been on your course and they completely ignore everything you’ve said!
Chris: You did not listen to me!!
Henry: That’s a good term too. I think I should I’d probably be rich if I’d did that. Every once in a while I charge somebody extra cause he made me work on Sunday – he wanted it done.
Chris: Oh jeez yeah.
Henry: Some consultants, if you hire them and they tell you something and you don’t do it they get upset. I don’t. My feeling is you hire me, you wanted to know what I think is wrong, how to fix it I tell you. I did my job, I earned my money now it’s your responsibility to do it or ignore it, I don’t care. I don’t get upset – I know people do get bent out of shape about that. I don’t care I did a good job and earned my money I feel happy with what I did.
Chris: You’ll happily come back and tell them the second time right.
Henry: If you choose not to follow my advice, that’s ok. Be my guest. Sometimes they don’t and sometimes they do. More often they do than don’t but there are examples of both. Or a lot of times I don’t know because you tell them something then go away and don’t hear from them. So either they are mad at me or everything’s fine
Chris: No thank you notes!?
Dave: How much of a big deal is ESD these days?
Henry: These days? It has always been a problem. The European Union has mandatory requirements for ESD, the US did not on commercial products. I do a reasonable amount of ESD consulting for clients. 1:10:10.8
Dave: Are there any common problems, traps that people fall into in that they haven’t protected their gear properly?
Henry: Well a lot of that … two fold – some mechanical you want to try and keep the ESD out as much as possible and putting breakdown filters and things on IO cables etc. number one. What I do, I go and put filter son the digital logic on the rests and interrupts and things like that so even if the transient gets in it doesn’t upset the logic. The ESD problem is one of setting the logic and having it change state.
Chris: So is there a way you discern between one kind of signal, obviously I mean resets a good one. Do you do chip selects as well for a SPI bus clarify* Like a chip select on a SPI bus? Would that be something you would do? More internal to a part? Or is it mostly the outward facing where the human interaction …
Henry: I do two things, where the cables enter I try and protect that and then I go and try to protect the sensitive IC devices and that’s kind of my approach to go both places.
Chris: That’s good thinking.
Dave: Do people have a lot of issues these days with low level component noise and stuff like that? Is that a big issue these days or are people beyond that because it’s all designed out because of the system blocks they’ve got these days.
Henry: I guess what do you mean by low level component noise?
Dave: Like op amp noise, thermal noise….
Henry: The inherent, intrinsic noise.
Dave: Yes intrinsic noise sorry yes.
Henry: Yes matter fact there’s a chapter in the book on that .. Not as much, you normally only get that if you are measuring very very very small signals.
Dave: It’s more of a niche market kind of thing.
Henry: That’s a very specific type of application.
Dave: That can get really tricky.
Chris: Yes it can. Laughs
Henry: Every once in a while I did do some consulting for a company that measuring very very small signals and that can be an issue there, that’s not a big issue that I get involved in nowadays – I don’t see it a lot.
Dave: I always find it amazing how the manufacturers analog devices will come out with the worlds lowest noise op amp and I’m going well ‘how the hell did you measure that – how did you characterize that?’
Henry: That’s true, that’s a lot of work and it’s difficult.
Dave: It’s almost black magic.
Chris: Like Keithley gear man
Dave: Some Keithley gear, well how did Keithley measure their own gear you know?
Chris: Metrology sciences are crazy.
Dave: You’ve got it.
Chris: One last question – we’re getting out there in terms of time. So you are a lifetime member of the IEEE? What does that mean?
Henry: A member until I die!
Dave: It means he’s been a member for a lifetime. When did the IEEE start? I don’t even know.
Henry: Let me answer the lifetime question first. What that means is you get your dues free. You stop paying them and lifetime of the IEEE society you can attend the symposiums for free.
Chris: Oh nice.
Henry: So there are some nice advantages to that. That’s usually a result of being a member for along time.
Chris: Buy forty years get twenty free, that’s a good deal I like that.
Henry: You talked about when the IEE started, well when I was in college there were two professional organizations. AIEE – American association of engineers and the IRE which was institute of radio engineers.
Dave: No mention of the word electronics back then!
Henry: See the AIEE back then the two bridges of electrical engineering were power and RF. The AIEE was the power organization and the IRE was the RF organization and in 1963 they combined to become the IEEE.
Dave: Ahh got it.
Henry: So it’s a combination of those two professional organizations. So the answer is 1963 and it’s a combination of those two. So if you were a member of one or the other you ended up a member of the IEEE. 1:15:54.8
Dave: Are there any more books in the planning stages?
Henry:What that I’m working on or I’m thinking about?
Henry: I’m thinking. Laughs.
Dave: Or is just too hard cause it takes years to write a technical book right?
Henry: Yeah really it does. The last one I came out with took me 3 and a half years basically, plus I’m working doing consulting work and everything too. It’s an awful lot. I put off doing it because as I say it started as a third edition, the publisher was after me to do a third edition and I just new how much work was involved. I didn’t want to commit myself. I finally said, if I’m ever going to do it I gotta do it. I decide to do it – I go slow on doing that. I have a though with another fella maybe we are going to come up with something I don’t know.
Dave: Got it.
Henry: It will probably be on antennae’s if it’s what I’m thinking about. Something different – simplified antennae theory.
Chris: Oh I like that.
Dave: That will be nice yeah are there any good books on that at the moment?
Henry: Well not on simplified – there’s a lot of good antennae books but they are all very loaded with theory you know.
Dave: Of course yeah – well I’d certainly buy that.
Chris: I would too.
Dave: Cause that’s another thing people don’t understand!
Henry: I kind of took a lot of the stuff and tried to simplify it and maybe that’s the thought of doing that with antennas also.
Chris: Could you do that with everything cause that would be great for me…
Dave: What subjects in electronics do you think are in need of a real simplified text. Have you noticed anything in the field that needs a simplified text, that’s cryingout for a simplified book? Antennas being one?
Henry: I think in any subject you could do that.
Dave: Excellent, Digital for Dummies?
Henry: I was going to ay all those ‘For Dummies’ books …Now some of them are too simple but a lot of them are good you know. I think if you get the right people who know how to do it you could have a book on simplified everything.
Dave: Is that, you know the practicing engineer. Most people do their engineering study and then they go into the world and they actually make things. is that all they have to worry about these days is the practical side of things? Do they have to go deep into the theory anymore? Especially in the education side of things should they be teaching more practical stuff?
Henry: Yeah well I think education should cover more practical stuff but the universities tend to think otherwise, in general. Don’t get me wrong it is important, understanding theory and developing .. like some of the exotic communication codes we use, modulation schemes, even FM radio is something fairly complicated to understand until the people worked out the math.
You often need the complicated theory to work out some of these schemes but then once we understand the schemes there is no reason you cant simplify it is what I say. I don’t think you can come up with everything in the world without knowing a lot of the complicated theory but once we get something I think we can simplify it down to amore understandable thing. I think frequency modulation would be a good example of that.
Dave: Who was it Chris that we had on about the TV stuff was it Ron?
Chris: Yeah Ron, Ron Quan and he’s actually doing a book on FM I think.
Dave: Yeah he is doing a simplified book … and just the art and science that went into the Beta and VHS video recording schemes. Very complex stuff behind that – phenomenal.
Henry: Yeah that’s a very good example yeah.
Dave: Do you think that there’s any hope of the Bell style research labs coming back in favor?
Henry: That’s a good question, a real good question. I think when they were here they were a national resource, do I think they are going to come back – no. I think everybody is too focused on the short term.
Dave: Profit, product and what product can we get out in the next nine months.
Henry: More and more – it was the next year and then 9 months, 6 months , 3 months I think. If you can’t get it on the market next week forget it!
Dave: I was going to use the example of Google there Chris. They have got a basic research lab – those big companies – there are a couple around that …
Chris: The ones that are cash heavy really..
Dave: The ones that are very cash heavy and they want to get a tax exemption on the R&D side of things.
Chris: God bless ’em.
Henry: I think one thing we are seeing too is so many companies are getting out of the hardware business just to get into systems and software and we’re moving so much of the hardware stuff overseas – out of the United States.
Dave: But is there a lot of innovation happening? I know a lot is still happening in Europe and places like China I don’t hear to many stories about here being huge basic research innovation in China.
Henry: Not that I’m aware of?
Dave: So who is doing it?
Chris: Well I think universities ….
Dave: Someone has to be advancing the state of the art somewhere. Yeah universities are still doing it of course
Henry: If you look at products of the last ten years, who has been the most innovative? Apple. IPads, IPods, they were products that didn’t even exist. They weren’t just changing the computer. They came up with products that didn’t exist.
Dave: But are they developing the basic technology behind it or are they more system level integration masters? 1:22:28.8
Henry:Well the idea first is to even think that this is what you want.
Dave: And then how to achieve it. We want to go to the moon – how do we do it?
Henry:A guy I always respected was Steve Jobs of Apple. At one time, he had a job at Apple, he was called the corporate visionary and I in my mind laughed at that. That’s just an excuse to give him an office and pay him. But you know, if you look in hindsight, he not only changed electronics – IPads, IPhones etc. He changed marketing – the Apple stores. He changed animation – Pixar. He sold it to Disney for 7.5 Billion. That’s what he did when he wasn’t at Apple.
I’ve been reading a bunch of stuff on this lately … apple is the most successful retailer in the world right now. The Apple store in NYC grosses more than Tiffany’s jeweler whish is down the street.
Henry: They just put a whole new spin on marketing. He came up with new ideas. Like the old story about the paper clip. A new idea doesn’t have to be complicated necessarily. It may be but you know it just …
Dave: So have we moved into that area where it has to be product driven research rather than just we’re just going to do a whole bunch of basic research and we have no idea … are those days kind of gone? Do you have to have an end product idea on mind and application end vision?
Henry: I don’t know but I think in most companies that’s true. Where there may be some basis research is some government sponsored stuff.
Henry: Yeah that would be one example,
Dave: Military stuff.
Henry: I don’t know, who knows where the next innovation is going to come from? Somebody gets an idea and it’s grows. It’s really an interesting field to be in and see what’s going on here. Would any of us have predicted what we have here today ten years ago?
Dave: No, nobody predicted the internet for example, nobody predicted mobile phones – back in the day.
Henry: Well, I was at Bell Labs when they developed cellular phones. AT&T didn’t realize the value of it. Nobody thought mobile would ever be the primary phone. A lot of people are getting rid of their landline.
Chris: Oh yeah that’s me.
Henry: The original mobile phone service was just an improvement in mobile phones for those people that needed it or wanted it in a car or something.
Dave: For that niche market they thought it would be a niche market.
Henry:Nobody envisioned it, and phones we got internet connection and everything through it. The smart phone is a whole new technology. The phone was a phone. Any maybe a camera on it. That was it.
Dave: So we need these visionaries who can think 100 years into the future, 50 years or 20 years. I can see this being a big thing even though you don’t think so. You think it will be a complete flop but I’m a visionary …
Henry: We got some companies – not necessarily electronics … I’ll give you a good example. Space X is a good one. They’re sending commercial space ships up to the International Space Station and who would think they would have come up with schemes to do that. 1:27:08.8
Dave: And they are headed to Mars! Fantastic driver.
Henry: If I go back 10 fifteen years ago, would people believe that we have home consumer products running at over 1Ghz frequency? No way.
Dave: Exactly and that’s not that long ago.
Henry: So if you ask me what’s going to come along in five years I have no idea. Maybe I might have a little idea in a year or something but five years from now I have no idea. Somebody will come up with something completely new – people will innovate that’s mankind – in electronics and …
Dave: Are we reaching the upper limit of practical electronics as we know if in terms of high frequency stuff? Are we currently pushing the boundaries.
Henry: That’s a very interesting point something I’ve thought about a lot in that for instance I don’t think you’re going to see frequencies increase much from now on. Functionality is going to get bigger and bigger. But you see what’s happening frequencies haven’t increased much in the last 2 years.
Dave: No they haven’t it’s all going parallel processing
Henry: That’s correct, we’ve got more functionality by paralleling multi chip computers things like that. I think technology will continuously innovate but in different ways. There for many years we said every year we said the frequency is going to double
Dave: Yeah yeah, that’s right – that stopped ten years ago
Henry: We’ve come to the limit of using standard epoxy glass printed circuit boards. Above a Ghz that’s a lousy dielectric.
Chris: Yeah so the costs …
Dave: Can you see any change in the way we interconnect circuits and parts?
Henry: Everybody keeps talking about optical.
Dave: Everything going optical?
Henry: Yeah on the board level … I don’t know maybe?
Dave: FR4 is too easy , it’s too practical at the moment solves so may issues whereas optical seems very difficult.
Chris: It feels like to me that other stuff to is all moving down onto silicon. So you pushing it all onto multi chip modules, like silicon on module or whatever
hybrid modules. Or even just all on the same…
Henry: Well larger and larger scale integration is what we’re going to see I think. Yep well that’s where it’s all been going. It’s all gone down onto silicon.
Dave: And we’re gonna need more people like you because we are pushing the boundaries even further.
Henry: Well the noise and EMC issues are not going to go away, the regulations are not going to go away. Somebodies gotta do something about that.
Chris: Yeah. well I think I’ve read the noise reduction techniques one I think I definitely need to run out and get the newest one.
Henry: It’s almost, as I say 900 pages twice as long as the second editions. I have a whole chapter there on PCBs, layout and stackout. Just talking about different combinations of layouts and different ways and the advantages.
Chris: Well we’ve got about roughly 5000 listeners. So hopefully you’ve sold another 5000 copies with just that chapter.
Henry:Sounds good to me. I’ll go for that.
Chris: Tell your publisher … it was The Amp Hour!
Henry:We’ll start another printing right now.
Chris: Henry thank you so much for being on the show we really do appreciate it. Your experience is unbelievable and I can’t wait to read this “third edition” – the newer book I think it’s going to be really great.
Henry: Well ok I enjoyed doing it, I enjoy talking about this stuff. It’s been almost an hour and a half. I didn’t realize cause time was flying like that. Time flies when you are having fun I guess.
Dave: And I’ve enjoyed your New Jersey accent.
Henry:Oh well it’s probably different.
Chris: Just great
Dave: Thank you very much it’s been awesome!
Henry: Ok guys bye.