Forrest Mims, Radio Shack, and the Notebooks that Launched a Thousand Careers

There was a time when Radio Shack offered an incredible variety of supplies for the electronics hobbyist. In the back of each store, past the displays of Realistic 8-track players, Minimus-7 speakers, Patrolman scanners, and just beyond the battery bin where you could cash in your “Battery of the Month Club” card for a fresh, free 9-volt battery, lay the holy of holies — the parts. Perfboard panels on hinges held pegs with cards of resistors for 49 cents, blister packs of 2N2222 transistors and electrolytic capacitors, and everything else you needed to get your project going. It was a treasure trove to a budding hardware hobbyist.

But over on the side, invariably near the parts, was a rack of books for sale, mostly under the Archer brand. 12-year old me only had Christmas and birthday money to spend, and what I could beg from my parents, so I tended to buy books — I figured I needed to learn before I started blowing money on parts. And like many of that vintage, one of the first books I picked up was the Engineer’s Notebook by Forrest M. Mims III.

Wish I could find my original copy from 1979. This one is on Amazon.
Wish I could find my original copy from 1979. I just bought this one from Amazon.

Many years rolled by, and my trusty and shop-worn first edition of Mims’ book, with my marginal notes and more than one soldering iron burn scarring its pulp pages, has long since gone missing. I learned so much from that book, and as I used it to plan my Next Big Project I’d often wonder how the book came about. Those of you that have seen the book and any of its sequels, like the Mini-notebook Series, will no doubt remember the style of the book. Printed on subdued graph paper with simple line drawings and schematics, the accompanying text did not appear to be typeset, but rather hand lettered. Each page was a work of technical beauty that served as an inspiration as I filled my own graph-paper notebooks with page after page of circuits I would find neither the time nor money to build.

I always wondered about those books and how they came about. It was a pretty astute marketing decision by Radio Shack to publish them and feature them so prominently near the parts — sort of makes the string of poor business decisions that led to the greatly diminished “RadioShack” stores of today all the more puzzling. Luckily, Forrest Mims recently did an AMA on reddit, and he answered a lot of questions regarding how these books came about. The full AMA is worth a read, but here’s the short story of those classics of pulp non-fiction.

Like many of us, Mims had no formal education in the fields that were to become his stock in trade. A graduate of Texas A&M with a degree in government, Mims was largely self-educated in electronics. After a stint with Air Force intelligence in Vietnam and an engineering assignment to the Air Force Weapons Lab that required special dispensation because he lacked an engineering degree, Mims continued to teach himself electronics in the early 1970s in exactly the way his Engineer’s Notebook would later document — one small project at a time.

Forrest M. Mims III. Source:
Forrest M. Mims III. Source:

After co-founding MITS, the company that would later go on to produce the Altair 8800, Mims was gaining quite a reputation in hobby electronics and as a writer. With a monthly column in Popular Electronics magazine by 1975 and a couple of volumes of hobbyist books written for Howard Sams and Company, Radio Shack’s technical editor Dave Gunzel approached Mims about working for them. He knew of Mims’ notebook style and asked if it would be possible to develop a book using the same layouts.

Mims rose to the challenge, hand-inking each page painstakingly on Mylar sheets. He recounts that “a single error required redoing an entire page,” and that the effort “drew blood from the middle finger of my right hand.” The first pages of the book were “typeset” with a Selectric typewriter to ease the reader into the hand-drawn pages to come. Illustrations and schematics were likewise hand drawn, and all by Mims himself.

The later Mini-notebook series were produced using similar techniques, although this time mercifully with a mechanical pencil. Each volume took about three weeks to produce, including designing each circuit and building it four times to make sure it worked.

Mims’ first Engineer’s Notebook would eventually sell 650,000 copies, with the updated Engineer’s Notebook II and the Mini-notebook series would only add to that total. The numbers are a testament to not only the content and the style of the books, but to the way in which Mims presented the subject matter – simple building blocks, easily understood as units, and moreover, easily built on a breadboard. The books practically begged the reader to experiment, and there’s no doubt they helped Radio Shack’s sales of parts and tools.

Image Source: Mims' Mini-Notebook 555 Circuits scans
Image Source: Mims’ Mini-Notebook 555 Circuits scans via

But the most striking thing about Mims’ books is their staying power. First published long before most of the core demographic of reddit was even born, the AMA is a running stream of appreciation for the works and how they launched many careers in electronics.

I’m also inspired by how Mims has monetized his life — he takes his love of science and electronics and just goes for his goal with great vigor, and without regard to his lack of formal education in any of the fields he works in as a citizen scientist. There are valuable lessons there for the hacker community, far and above how to build a monostable multivibrator from a 555 chip.

[Featured and Thumbnail image source: Engineer’s Mini-Notebook Basic Semiconductor Circuits by Forrest M. Mims, III.  Scanned images from]

137 thoughts on “Forrest Mims, Radio Shack, and the Notebooks that Launched a Thousand Careers

  1. Recollections: I had all of Forrest Mims’ books. I even worked at Radio Shack for a while and was happy when people bought his books.

    I built his “infrared communicator” project one year for a 4-H electronics project when i was 15 or so, but I was ashamed that I never got it working. I built the transmitter and receiver into (big) flashlight housings with little slip-in circuit boards and mounted the LEDs and diodes into the focus of the parabolic reflectors. With the gain controls on the outside of the housings. It should have been sweet. But it didn’t work. I never made it work. For my 4-H project, I mounted the transmitter and receiver (with hot glue) onto a board pointing away from each other so that that nobody could test them. It was not my proudest moment. I wished that I could have made them work.

    Flash forward to many years later, and I thought about the project and I instantly realized that I didn’t understand the difference between +9V and -9V and ground. The project evidently required an 18V supply, but I didn’t understand that. I think that I wired -9V to ground, thinking they were equivalent. I was stupid. I wish the books would have shown how to obtain that voltage spread with maybe two 9V batteries and a ground between them (or however you were supposed to obtain an 18V differential.) I know it’s my fault, but a slight bit of help would have helped me.

    (I went to engineering school and found that circuits that wrote Vcc and Vdd were also the enemies of understanding.)

    I recently found that those old infrared communicators may still be at my parents’ house. I want to try and make them work. I would love to see them work and redeem my childhood. I still feel failure about what I did with them.

    Years later, I build circuits, but my aesthetic has changed. I intentionally draw circuits so that information flows from left to right and that they are modular. One basic circuit on each page, ideally. “Here’s how each circuit feeds the input of the next.” “Here’s what parameters affect the operation of each circuit and how to calculate their effects.” “Here are the equations you can use to calculate the effects of varying components.”

    Electronics are hard. I wish I had had a mentor when I was 14. Or me going back in a time machine explaining the things I didn’t understand.

    1. To be fair, these books were not meant to be standalone texts to learn electronics from scratch.

      I worked hard to get an understanding of electronics. The concepts of grounds and voltages were quite a mind twister. Vcc, Vdd, Vee, Vbb, etc., depending on if the circuit was CC, CB, CE, if it had negative supplies, if it used JFETs, etc. So don’t be too tough on yourself.

      I built a shortwave radio from plans in a book. The plans were rather old at the time and used PNP transistors, and I decided to build it using more modern NPN transistors. Working out all the changes was an interesting learning experience.

      I hope you are able to find those IR communicators, and get them working.

      As for what you said about signal flow left to right and modular… maybe you can convince a world used to Make: Magazine’s sloppy “schematics” to stop publishing pictorials and strange schematics with seemingly random signal flow directions. A pox on Fritzing.

      1. I agree on all points.
        1) There were plenty of books out there that taught the fundamentals, and books like Mims’ were great for giving a kid a bunch of simple circuits to try out, and hopefully build confidence by getting them to work.
        2) Right to left!!! I’ve encountered quite a number of circuits that didn’t make any sense at all, but when redrawn for left-to-right signal flow and top-to-bottom current flow, became simple.
        3) A POX ON FRITZING! The very notion that a rendering of a circuit on a solderless breadboard is useful, is puzzling at best. And from the grudging tutorial on Fritzing that [Benchoff] wrote, it would seem that the implied development flow is from breadboard to schematic to PCB, which I’m sure leads people to wonder, “why did I need the schematic?”

        1. I did a class on drawing and reading schematics for our local makerspace, OlyMEGA. For good examples, I used schematics from EDN magazine (Electronic Design News).

          For bad examples, I drew almost entirely from Make: Magazine. Sad.

          One of my big pet peeves is beginners being taught bad methods.

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