This page updated July 8, 2017.

This section contains research work that I have done over the past 50 years. Time flies when you are having fun.

I read this book when starting work on a masters degree in physics. Picked the invariant imbedding chapters to do my thesis. The purpose was to replace the Coulson et al book with tables for a Rayleigh atmosphere with more accurate and stable numerical results.

Here is the published paper and the codes for the results for an Invariant Imbedding solution for a Rayleigh plane parallel atmosphere. Found a copy of the article on the Internet.

To reproduce the results on a Linux system with gfortran installed.

gfortran -fno-automatic -o rt01 rt01.f ./rt01 < 001 > 001.scalar.out gfortran -fno-automatic -o rt02 rt02.f ./rt02 < 001 > 001.vector.out

These two codes were the first programs that I ever wrote in my life. Done on an IBM 360/50 using FORTRAN IV compiler. I was a summer intern at Texas Instruments in Dallas TX. We had two IBM systems in a duplex mode. I was given use of one of them for 12 hours on a Friday night to run both programs and it took most of that time. O/S was the old PCP (Primary Control Program) before HASP (Houston Automatic Spooling Program), so jobs were loaded using decks of IBM hollerith cards. Those were the days. Now both codes take less than 2 seconds total for runs to larger optical depths than published in the paper.

rt01.f is commented and rt02.f is not. Maybe, some day, I'll come along and do the work. Until then use both codes and compare the comments, if you are interested in the details of the code. The no-automatic option is required because the original IBM FORTRAN compiler used static allocation of memory and not call by reference, thus one of the calls generates a local variable and the results are not passed back to the main routine. I just haven't modified the code yet and I have to spend some time locating the minor problem. My preference is to rewrite everything in C.

Here are two papers I have written up on how to do backward monte carlo simulation of photons scattering in an atmosphere by starting at the detector instead of the energy source. Thus the name backward monte carlo. Results are compared to the benchmark in the previous section using invariant imbedding.

My freshman year of high school. Something happened that has caused me problems ever since then. In algegra 1, Tabor Rowe (the teacher) had us pick the problems we would work at the end of each chapter and turn in the list the first week. Each student did his/her own list. I turned in the list, but I was having so much fun doing the problems that I did them all at the end of each chapter. The same year, Mrs Mildred Howard taught us penmanship and would not allow us to use anything other than a fountain pen for writing. We all bought the old Big Chief writing tablet and practiced penmanship for six weeks after school. To this day I still write with a fountain pen. Did all my homework in ink through a bunch of college degrees. Bugged the hell out of math instructors. :-)

From time to time I love to take a book and go through it. This year it is circuit theory. Had one course at MIT on the topic, but not a detailed course like the two books below. So I'm picking one and going through it. Won't be doing all the problems. Too many and time is short. Goal is to work two chapters a week. Start at the beginning and go to the end. (Alice in Wonderland line.)

I thought you might be interested in following along on a circuits course. There are two textbooks written by Boylestad and another by Paynter. Don't know which is better. Way to find out is look at them. Let's start with Boylestad first. Two chapters per week for starters. March 20th is the first day of spring. Let's grow something. Our knowledge of the Universe.

And here is a copy that you can read online without having to download.

And if you won't cheat but work the problems first before checking your answers, here is the solutions manual to the 10th edition, so not all problems, but a lot..

Here are the chapter titles for each book for comparison. I like the Paynter book as there are some chapters that will lead into some ham radio transceiver design discussions later. IMHO.

Introductory Electronic Devices Electronic Devices and Circuit Theory and Circuits 6th Ed Seventh Edition Robert T. Paynter Robert Boylestad and Louis Manhelsky 1010 pages 2003 934 pages ------------------------------- ------------------------------------- 1 - fundamental solid state principles 1 - semiconductor diodes 2 - diodes 2 - diode applications 3 - common diode applications: 3 - bipolar junction transistors basic power supply circuits 4 - dc biasing -- bjts 4 - common diode applications: 5 - field effect transistors clippers, clampers, voltage multipliers 6 - fet biasing and displays 7 - bjt transistor modeling 5 - special applications diodes 8 - bjt small signal analysis 6 - bipolar junction transistors 9 - fet small signal analysis 7 - dc biasing circuits 10 - systems approach -- effects of R_s and R_L 8 - introduction to amplifiers 11 - bjt and jfet frequency response 9 - common emitter amplifiers 12 - compound configurations 10 - other bjt amplifiers 13 - discrete and ic manufacturing techniques 11 - power amplifiers 14 - operational amplifiers 12 - field effect transistors 15 - op amp applications 13 - mosfets 16 - power amplifiers 14 - amplifier frequency response 17 - linear-digital ics 15 - operational amplifiers 18 - feedback and oscillator circuits 16 - additional op amp applications 19 - power supplies (voltage regulators) 17 - tuned amplifiers 20 - other two-terminal devices 18 - oscillators 21 - pnpn and other devices 19 - solid state switching circuits 22 - oscilloscope and other measuring instruments 20 - thyristors and optoelectronic devices 21 - discrete and integrated voltage regulators Appendices Index

After doing some of Boylestad, I have decided that I will be doing Paynter instead. You can do Boylestad, since there is a solution manual. Paynter has answers at the end of the chapters.

Equation 2.3 in Paynter is wrong. Completely wrong. Look at it and see if you can figure it out. Then go to your browser and google for 'precentage of error' and look at the top of the page. The correct formula is PE = (x - x')/x' * 100 %. Where x is measured value and x' is the calculated value using correct and complete analysis. This means that there are several generations of students that will be doing it wrong. Some one should have caught this decades ago. I will be using the correct formula throughout the book.

You do the problems first without my help or looking at the answers in the book before completing what you think is correct. Double check, then look. I will be working through the problems in the same manner. I will not have the following checked until I finish all the problems I want to work. I will check afterwards and you will know I have done this when you see the next chapter solutions posted. This means that this is work in progress until I go to the next chapter. It's my walk down the road. :-) Enjoy and learn something today and every day. Life is short.

Some one is going to email asking about the spacing. I have not tried to get as many problems solved per page as I can. I'm not trying to waste paper, our number one renewable resource in the USofA. About 17 years ago, when we moved from Dallas to Prescott, Staples had notebook paper sales just before the start of each school year. They sold 500 sheet packages of college lined notebook paper for twenty-five cents a package. Needless to say I recognized a deal when I saw one. Have a stack of unopened packages over 1 meter high. I want to use it all up before the estate sale. :-) This project will help. I have a fountain pen from China that I paid less that two bucks for and item number 1645538849018 on ebay.com for 2 liters of ink to use. I'm going for the brass ring. My guess is that fountain pens are so cheap because there is no demand for them any more. A friendly environmental tool, 'cuz you don't need but one pen that you can continuously refill until you wear it out, which I have never done in my lifetime.

In the 6th edition there is an error in equation 2.3. It looks like the book uses the correct formula in the working of the problems. Here is a reference for you to compare (2.3) to the correct formula.

OK. For some solutions I found that I scanned them and posted them and then checked the answers with those in the book and then found a calculator error. My bad. Rusty at using the calculator. Thanks to computers. It is not worth my time and effort to go back and rescan, so just beware that a couple of problems are off on the answers.

Use qrz.com to find my email address using K7QO.