TRS 80 PC 1

TRS 80 PC 135 years ago, this July, I bought my first computer. The Radio Shack TRS-80 PC-1 Pocket Computer. Don’t laugh. It had BASIC and I wrote my very first program of any kind on it, one which
became an integral part of the retail and wholesale agricultural fertilizer / chemical dealership that I owned at the time.

The object of the program was relatively simple, but using this, along with the print out, saved a lot of time calculating how long a tank of anhydrous ammonia (NH3) would last on an applicator of a given width and travelling at a given speed. My delivery drivers used the output to determine when the farmer would need another “drink” of NH3 and whether the desired rate was being applied.

Inputs were:

  • pounds of actual nitrogen per acre required
  • total acres to apply
  • applicator width
  • applicator tank capacity (to 85% – same setup as with propane; tank and applicator combinations varied)
  • target speed

Outputs were:

  • hours and minutes until empty from full (85%)
  • hours and minutes for depletion of 5% (gauge graduation – used to check accuracy)
  • number of “fills” for total acres (used for our scheduling)

TRS-80 PC-1 Pocket ComputerThe only programming training I took was right out of the PC-1 manual. This was the first time that I had ever attempted something like this. But it worked! The bulk of it was done over the course of a weekend back at the in-laws; that is always a good “excuse” to be “engrossed” in something work-related. I verified numerous tests via the old-fashioned method and yep, they jived. So much for alphas, betas and RCs; test it and go!

Here is a blurb I found online that was from the Radio Shack promo as well as a review.

The TRS-80 PC-1 is the first-ever BASIC-programmable pocket-sized computer! It’s actually the Sharp PC-1211, sold by Radio Shack in the US.

It takes deep-pockets to hold the PC-1, but not to buy one. Costing only $230, it was very portable and useful.


This new TRS-80 Computer is another “first” from the company which brought you the best-selling, world renowned TRS-80. A truly pocket-sized Computer (not a programmable calculator). Of course it is an ultra-powerful calculator too… And it “speaks” BASIC – – the most common computer language, and the easiest to learn. You’ll soon be impressed by the phenomenal computing power of this hand-held TRS-80 – – ideal for mathematics, engineering and business application. end quote

For those who prefer hardcopy, the $149.00 Printer/Cassette Interface is superb. It is a miniature dot-matrix printer (not a thermal printer) as well as a Cassette Interface for data storage/retrieval.

Built-in rechargeable Ni-Cd batteries supplies power when the external power adapter is not being utilized. Unfortunately, the printer prints 16 characters-per-line, while the PC-1 display is 24 characters wide.

Yep, 35 years ago I got my start in this crazy world of computers with this little fellow. Sure wish I would have kept it.

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  1. My first computer was about 30 years ago. It was after they started making clones of the IBM Desktop. I don’t even recall the knockoff brand but I do remember it was a screaming 4.77mhz with about 256k ram and an amber screen. Plus it had dual 5.25 floppies. I replaced one of the floppies with a seagate 40mb half-height internal hard drive. I remember thinking it can’t be much better than this because I could boot DOS right to the hard drive and have plenty of space left for storage. How the times have changed.

  2. My first computer was a Redstone clone of an Apple II+ bought in 1982 or so. Dual 320kb floppies, no hard drive and 64KB of memory. It had the best manual ever and took me from switching on the machine to writing a game in Applesoft BASIC.

  3. Can relate. Had several early adventures with PC’s. Then big rollouts. Happy to know how to manage my PC’s for as long as PC’s have been around. My first was an IBM 5100 with Basic and APL. Just getting ready to tackle my first WordPress site. Happy to land on you site.

    1. Hi Dominique,

      Yes, the PC has certainly come a long way since back then!
      Thanks for stopping by 🙂


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