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Estimated reading time: 7 minutes
Tim's Takeaways: Some Timely Advice
Have you ever heard of Bert Christman[1-2]? Bert was a storyteller, a graphic illustrator to be exact, and in 1936 took over as the lead writer and illustrator of the nationally syndicated comic “Scorchy Smith.” As a daring pilot/adventurer, Scorchy’s stories fed into the public’s interest in aviation that had been fueled by the exploits of Charles Lindbergh and other notable pilots of the day. Under Bert’s guidance, Scorchy soared to new heights in aerial adventures, and the comic’s popularity continued to grow. But that wasn’t enough for Bert Christman, who wanted to find new ways to connect to his readership with realistic stories and illustrations of Scorchy’s flying adventures. To accomplish this, he took his research to the next level with flying lessons and quickly earned his wings.
In the late 1930s, Scorchy Smith’s adventures expanded beyond the domestic problems that readers were used to, and he faced new levels of international threats coinciding with real-world turbulences. At the same time, Bert decided to put his writing on hold as he joined the U.S. Navy as a dive-bomber pilot. Not only did he want to defend his country, but he wanted to broaden his understanding of aerial combat for future stories with the real-life experiences of being a combat pilot. Three years later he left the Navy to join the American Volunteer Group, otherwise known as the Flying Tigers, in the defense of China. It was here that Bert’s life literally blended with his writing as he lived the same type of adventures that he had penned for Scorchy Smith and other heroes in the comics. Bert commented on this dangerous life in a letter home, “Things are getting hot here. Even Scorchy Smith would be satisfied.” Sadly, this is also how he met his fate when shortly thereafter he was shot down during a dogfight in January 1942.
I realize that this story doesn’t have anything to do with the printed circuit design and manufacturing industry, but it is a real professional motivator for me, so let me tie it all together. In this edition of Design007 Magazine, we are exploring advice from the experts. As I was pondering some of the things that I’ve learned or wished that I had learned along the way, the story of Bert Christman came to mind. What I find so captivating about him is that he was willing to put everything on the line in order to improve his abilities in producing a better product. I am not at all suggesting volunteering for hazardous duty pay to improve our DDR routing skills, but his story does serve as an inspiration as to how committed a person can be in improving their skills and abilities. I just wish that I had learned this lesson a lot earlier in my career so I would have had more time to put it into practice. Maybe I might have learned a few other skills in my professional journey as well. In fact, if I had a time machine, here are a few other pieces of advice that as a designer I would have liked to have known earlier too.
It's ‘Circuit Board Design,’ Not ‘Place and Route Design’
When I was first starting out in PCB layout, I was fascinated by placing parts and routing nets on the screen as any new designer is. Soon I came to understand many of the nuances of PCB layout, and how the different spacing rules applied in the art of place and route. But I also made a lot of mistakes that could have been avoided if I had only grasped the concept that I was actually designing a “circuit board” as opposed to simply performing place and route. I remember not understanding—and therefore ignoring—some of the early signal integrity problems that were being discussed around me. These included topics such as broadside coupling and signal return paths, all of which were important to what I was doing. Thankfully, my work was monitored by senior designers, and I don’t believe that I caused any serious damage. But if I could, I would sit the younger version of me down and explain that layout is an all-encompassing process that begins with the schematic, and not when you start throwing parts on the screen.
Board Integrity Starts With Library Integrity
Like a lot of designers eager to get rolling on their first layouts, I was happy to grab any old part out of a library and throw it into the design. What I didn’t fully realize at the time, though, was how essential a properly built PCB footprint is to the manufacturing process, and that real-life components would eventually have to be soldered to these land patterns. I shudder to think of how many times I may have swapped an anode for a cathode in some of my first layouts. Thankfully, this lack of attention to detail didn’t seem to result in too many actual problems, although I do remember having to go back and make a few corrections here and there. But again, with the Wayback Machine dialed into my earliest days of PCB layout, I would explain to my younger self the entire concept of circuit board manufacturing from start to finish. I would then explain how manufacturing relates to design and the importance of choosing the right footprints for the parts in the BOM. I would make sure my younger self understood the critical importance of dimensionally accurate footprints and land patterns, emphasizing that even one incorrect pad size could put the whole design in jeopardy of failing.
PCB Design is Not Just About Me
I’m really embarrassed to even admit to this one, but sadly it’s true. As a junior designer, I tended to look upon the input of other members of the design team as being more of an annoyance than the collaborative partnership it should have been. Now, it is true that the working relationships between team members need to be managed appropriately, and not everyone can get everything in a design to be the way they want it to be, but I was completely out of line in my earlier days when it came to design change requests. “Move this part closer to that one? No way, that will mess up my beautiful routing.” “What do you mean that will cause a manufacturing problem? Who cares? The design looks great.” Once again, if we could just run the DeLorean up to 88 mph, I would give my younger self a good slap and convince him that the sun doesn’t rise and set with how the design looks. The priority is that the circuit board must actually work and be manufacturable above all. Great Scott!
Getting Your Ducks in a Row Avoids Getting All ‘Fowled’ Up
It is amazing when I think back to how many times I rushed through important parts of a project, just so I could get into the “fun stuff.” Here’s one example that caused me grief on more than one occasion as a junior layout designer: “Oh I don’t need to worry about all of these separate design rules, let’s just set the default and start hooking up traces.” Are you wincing right now just as much as I am with that memory? If I could just convince the Guardian of Forever to send me back to the first occurrence of haste in my career, hopefully, I could change the course of history. I would tell myself that taking an extra 30 minutes up front is much preferable than the hours of re-work that I was headed for later.
Relax, Have Fun, and Don’t Take Yourself So Seriously
And lastly, I would borrow the phone booth from Bill and Ted long enough to advise my younger self to lighten up just a little. When I first started laying out boards, I could be kind of intense, which didn’t always work out very well. I would get down on myself for mistakes that I had made, while at the same time trying to manipulate people into doing what I thought was best. There is so much joy to be found in what we do and who we work with that such a high level of intensity just isn’t necessary. Plus, it isn’t very healthy either. Please don’t misunderstand me. We still need to be diligent in our work, and always aim to improve ourselves just as Bert Christman did. But we don’t need to kill ourselves and those around us doing it.
And speaking of killing ourselves while working, my wife is in the other room watching basketball all by herself, and I think that I am going to join her for a while. Keep on designing everyone, and I’ll see you next time.
References
- Life Imitates Art, Colorado State University Magazine.
- Cartoonist Bert Christmas Did Not Survive War, The Daily Cartoonist, May 31, 2021.
This column originally appeared in the July 2021 issue of Design007 Magazine.
More Columns from Tim's Takeaways
Tim’s Takeaways: One for the ArchivesTim’s Takeaways: The Art of Technical Instruction
Tim’s Takeaways: PCB Design and Manufacturing—Let’s Work Together
Tim’s Takeaways: Take It From Scotty, Simple Really is Better
Tim’s Takeaways: Human Ingenuity and the Rigid-flex PCB
Tim’s Takeaways: How I Learned Advanced Design Strategies
Tim’s Takeaways: Batter Up—Stepping Up to the Substrate
Tim’s Takeaways: Tribal Knowledge—Not the Villain You Thought