I am not a calculator collector, I am not a calculator collector.

I am not a calculator collector.  I have to keep saying this to myself because I don't need another genre of items to collect, but I'm quite tempted by this since it is adjacent to retro computing.  I've managed to avoid printers (mostly), typewriters completely, and vintage test equipment, among many other interesting items that I would collect if time money and storage space were not limited.

So I have a few calculators.  I purchased a Radio Shack Pocket Computer 4 off Facebook Marketplace in 2020...


And since then I've been picking up interesting, older calculators from the 70s and 80s at Garage Sales and Thrift Shops when I can find them including a couple of hand held Casio units.  My parents had a Casio on their desk, it had a mesmerizing Nixie tube display and so although it was "portable / battery powered" it stayed plugged in and on the desk.  The Calculator Wars of the 70s were historically significant to the development of home computing as they occurred right before the home computer revolution and included many of the same companies.  Calculators were the "killer app" of Microprocessors before the home computer revolution began, but this is well covered elsewhere.

My personal calculator history started with my first graphing calculator, a TI-81.  My parents bought this for me while I was in high school and I spent quite a bit of time puttering with it and even wrote some simple programs to run on it.  I was recently able to reacquire a TI-81 from Free Geek Twin Cities and add that to my calculator not-a-collection.

My favorite calculator is the HP48G which got me through engineering school.  Back in the day we didn't have laptop computers for every student so pretty much everyone had an HP 48 of some sort.  It was hard to learn how to use it, but once I'd gotten the hang of it I can always come back to an RPN calculator, just like riding a bicycle, you never really forget how.  There's a review video from Calculator Culture on YouTube that I'd recommend, it has helped me understand why this calculator is so unique.

I wore out my initial 48G calculator.  I had tried to repair it at one point, but it was not designed for service and I ended up breaking mine.  I missed having it enough that about ten years ago I had purchased an HP50G calculator hoping that it would replace my worn out calculator, but I didn't like using it as much.  Another Calculator Culture review video explains this calculator well.  I ended up selling my HP50G as it didn't really match my expectations and was different enough from the 48 that is just didn't feel the same.

So after watching a few videos from HPcalc.org's recent conference and the Calculator Culture videos I realized that the best way to "Scratch the Itch" so to speak would be to just go ahead and buy an original HP48G.  With my new knowledge about the hardware revisions and the typical problems, I was hoping I could find a nice one on eBay at a reasonable price, and after waiting and shopping for a couple of weeks, I was able to find this lovely unit here...


I've paired it with the original manual set that I'd kept all these years.  I'm glad I kept the manual since there's alot I've forgotten about how to use the machine (the manual is hundreds of pages long).  As described in the review video above the LCD screen isn't great, the contrast is poor, although not being backlit means that the battery life is quite good.  The keyboard is amazing, the keys are clicky, very tactile and enjoyable to use.

I've enjoyed having this machine back at my desk, and I'm getting back into the habit of using it.  During my research I've also found a much more modern iOS app that emulates the 48.  I've used about a half dozen of these over the years since getting my first Smart Phone and this one is the most useful and stable, it's called iHP48 and it is much better than other iOS Apps that emulate HP 48 which I have used before.  This is the main calculator app on my phone now and I use it almost daily.

Doing the research about HP 48 and being exposed to other calculator collectors has helped me learn about the history and development of the handheld scientific calculator.  I've become aware of the first Handheld Scientific Calculator, the HP 35 from 1972.  But this is a story for another day, so I will wrap up this bLog post by simply stating the obvious, I am a calculator collector.

My Newest, Oldest Apple II Plus (1979)

There were three very important home computers that came out in 1977, the Commodore PET, the Apple II and the Radio Shack TRS-80 Computers.  We retroactively call the Radio Shack the TRS-80 Model 1 but that is not how it was advertised at the time.  Also, the use of the term trinity to describe these three computers is something that appears to have begun in the mid 90s.

One of my goals in the Retro Computing hobby is to own all three of the original premade personal computers that didn't have to be built from kits like the Altair 8800.  So far I have been able to acquire; an Apple II Plus from 1979, a Commodore PET 4016 from 1980, and an original TRS-80 Model 1 computer.

Recently on a trip to Free Geek Twin Cities I was able to acquire another Apple II Plus machine and this turned out to be a machine from 1979.  This got me thinking again about wanting to get as close as possible to an original Apple II experience from 1977 and so I started doing research.  Tech Time Traveller has a really helpful video on this topic here.  He also painnstakingly built up this list of machines have have sold on eBay, since eBay doesn't keep pricing information and old listings around on their site very long  Thanks Tech Time Traveller!  Now that I know an original Apple II from eBay is probably more than I want to spend right now, what are my options?

Going back to the machine from  Free Geek, I learned that the board in my "newest" Apple II Plus is a "Revision 4" logic board.  This is from the period in 1979 was when Apple was making both the II and the II Plus at the same time, and often with the same logic board and only different ROMs and different RAM amounts.

At the same time as this was going on a listing came up on eBay for a computer that was listed as an original Apple II machine, but after inspecting it it seems likely that this machine had been upgraded to II Plus, which I later confirmed was the consensus in one of the Apple II Facebook groups.  I'm still considering the option of building an "Original Apple II" by getting bits and pieces and putting them together, but I think I'd rather hold out and wait till one comes along that is more complete locally, or with a backstory that I can learn about.

In the meantime, I learned about the Apple II ROM card, which was a period correct accessory card from 1979 that folks bought when they were upgrading their Apple IIs to Apple II Plus which allowed them to put the old ROMs onto an expansion board and switch them in at will from a switch on the back of the computer.  I used to have a modern card that did this, but ironically that card failed, so I set out to find a vintage card that still had the correct ROMs on it (Many, perhaps most of the ones on eBay have been stripped).  This article on the VCFed forums explains which ROMs where the period correct ones for an original Apple II (With Woz's Integer basic, and without Applesoft Basic).  I was able to find and acquire one of these period correct cards with the full ROM set, and it works great...


So, as of this writing, my Apple II Plus behaves in exactly the same way as the original machine, so I am now able to explore software from that era.  A good win for a reasonable price with parts that are still relatively inexpensive.