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Priming the Pump:

How TRS-80 Enthusiasts Helped Spark the PC Revolution

    About the Authors

Since closing out their TRS-80 software business in the mid-1980s, David and Theresa Welsh have been busy raising their daughter and active in IT work, community involvement, and writing/editing/photography endeavors.

Before he immersed himself in Z80 programming, David had been a professional photographer. He returned to doing occasional photo assignments, and, more recently, has been working on digitizing and cataloging his considerable accumulation of images, mostly in black and white film. David played an active role in his daughter's education, establishing a computer lab at her elementary school, using old, donated computers. Theresa served as a "Picture Lady," introducing kids to computer art.

After the demise of the TRS-80 business, Theresa worked at EDS as a technical writer, then moved to Ford Motor Company in various contract positions through the 1990s, serving as newsletter and web editor at the Scientific Research Laboratory until the auto industry cutbacks in 2005. She went on to take technical writing gigs in banking and healthcare. David also did contract assignments as a technical writer and consultant during this period through Explainamation ( He has served as chairman of a local organization working for community development in the interests of residents along the border between Detroit and its northern suburbs.

Theresa co-authored an award-winning business book (The Brave New Service Strategy, with Dr. Barbara A. Gutek) and wrote a novel for young adults, Tara, Initiate of Heliopolis and has done editing for other authors. She manages and creates content for her website,, and at (see her profile page), where she has over 200 reviews.

Daughter Amy spent her senior year in high school as an exchange student in the Czech Republic and traveled thoughout Europe. Today she lives in New York City where she is an artist and does promotional work.

BOOKS ABOUT DETROIT   David and Theresa have pursued their interest in exploring their adopted city, Detroit. During the city's bleakest years, they made many photo forays to document what was happening in the Motor City. Theresa has published an eBook guide, A Guide to Post-Industrial Detroit: Unconventional Tours of an Urban Landscape. Together, they have created a photo book, Detroit's Spectacular Ruin: The Packard Plant.

See more information about these books on Theresa's website,


We enjoyed the sights at the Chicago show

Remember the Dynatyper?

The Dynatyper connects to your TRS-80 and sits on your typewriter keyboard; it presses the keys down in place of your fingers.

Vernon Hester at the Chicago Show

Vern Hester, author of Multidos, at the booth for Level IV Products, one of a number of local Detroit area computer businesses that sold TRS-80 products.


We were the first presenters at the 2007 Vintage Computer Festival (VCF) in Mountain View California at the excellent computer museum in that city. We found an enthusiastic audience for our slide show, which used a lot of the old ads and photographs. Several media organizations interviewed us and gave us a chance to discuss what happened in the late 1970s that led to the explosion of personal computer use. We've attended a number of VCF events to promote our book and spread awareness of the real history of computing.

Priming the Pump has been a steady seller and as of 2009 is in its second printing.

Some of the vintage items in the Computer Museum at Mountain View CA

A Difference Engine, built out of erector set parts, at VCF in November '07

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 Apple iPad $9.95.

TRS-80: Thirty Years and Counting

Great years continue for our book, as the TRS-80 passes its 30th anniversary in 2007. We've had nothing but favorable comments from our readers. I got a wonderful email from a former Radio Shack employee who wrote:

   "Thank you for writing the book! I was delighted to find it on Amazon and read it over Christmas. It was nice to read so much background on the events I experienced working for Tandy from 1980 to 1993... Reading your book brought back so much. Time spent at the store as a salesperson, learning most of what I knew about the TRS-80 from our teenage customers! The blitzes. Disk doubling punches. An absolute prohibition on outside software and magazines in the store. Every model you mentioned and some you were too kind to mention such as DT-1 and DT-100 terminals, a slew of roman-numeraled printers, the phrase "near letter quality", and millions of dollars in ill-conceived marketing."

David and Theresa Welsh in 2014,
at the Packard plant in Detroit.

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