Rare pair

[Chasfield]

Attached is a shot of two Anita scientific calculators from my collection. The the smaller one, with a red LED display, is a model 841, built around 1975. This is the last stretch of the original, high quality Sumlock Anita 811 pocket calculator hardware and it was made in England out of aluminium and other good stuff. The larger, green VFD equipped unit is a model 202/SR and was built very shortly after Anita's takeover by Rockwell international. It carries their logo in the top right-hand corner. It is functionally identical to the 841. Note the handy square-and-accumulate shifted function available on the decimal point key of both units. Production of the 202/SR was farmed out to Rockwell's Mexican facility, though Anita badging was retained for European marketing purposes.

The 40 years past relationship between Sumlock Anita and Rockwell somewhat resembles that which exists between Nokia and Microsoft today - acquire and mangle. Rockwell soon lost interest in calculators and wound down production, wiping the original Sumlock Anita operation off the UK map at the same time.

[Tugdual]

I like that, totally 2001 a space odyssey look. Also it is the first time I see 2 columns of operators side by side.

[Chasfield]

I just discovered a feature that I had not previously noticed on these calculators. Shifted-f (f,f) invokes "dr", which presumably stands for delete right because it removes the right-most digit, while preserving f mode for the next function call. I assume this must be there as an option for situations where the operator believes the least significant digit to be worthless, or at least better rounded down.

Neither the calculator can handle standard form display or input. You needed to use it like a slide rule and have a notepad to hand for working out your exponents.

The 841 is a miracle of packaging, with a triple decker sandwich of PCBs contained within its small casing. The keys are of double shot construction and the calculator has a wonderful heft to it, once the AAs are installed under the slide out rear cover.

[Accutron]

I just sold a 202/SR at Hamvention last weekend.

[Chasfield]

Did it go for a reasonable price? I bought my 202/SR for 10 GBP, as the only bidder. It was one of those auction items that passes through almost unnoticed, despite it being an item of interest to British calculator collectors.

[Accutron]

I got $6 for it. We sold maybe 40 calculators all weekend, but it was the only Anita/Rockwell in the bunch. I used the law of conservation of calculators to buy this...

[striegel]

(05-26-2016 10:59 AM)Accutron Wrote:  I got $6 for it. We sold maybe 40 calculators all weekend, but it was the only Anita/Rockwell in the bunch.
...

I may have been one of your customers, as I came home from the Hamvention with 3 calculators myself:

• Casio fx-82B
• Radio Shack EC-4027
• The Educator Intermediate Overhead Calculator
  

That Nixie tube NCR calculator of yours looks like a nice acquisition.

[Accutron]

I know we had one of those Stokes Educator overhead projector calculators and a Radio Shack EC-4027, not sure about the Casio though. We were the only vendor with any real quantity of calculators, so if you saw more than one or two machines on the table, it was definitely us.

The NCR calculator is actually a rebranded Busicom 162 from 1967....Signetics ST600 series DTL and 256 bits of Mitsubishi core memory.

[Steve Simpkin]

(05-26-2016 06:03 PM)Accutron Wrote:  The NCR calculator is actually a rebranded Busicom 162 from 1967....Signetics ST600 series DTL and 256 bits of Mitsubishi core memory.

More information:
http://www.oldcalculatormuseum.com/ncr18-2.html

[rprosperi]

This cool thread is chock full of interesting notes on old machines, unusual features, manufacturers, etc. but for me, the real gold was here:

(05-26-2016 10:59 AM)Accutron Wrote:  ... I used the law of conservation of calculators to buy this...

I've been searching for some fundamental law of physics to blame it on, and this provides just the reference I need.

I thank you for that Accutron!

My wife... not so much.

[Accutron]

Calculators can neither be created nor destroyed - only transformed. Through the process of calculator fusion, you can turn a bunch of Rockwells and Casios into a single, larger calculator, with a requisite release of energy that can be measured as an increase in your wife's blood pressure.

[jjohnson873]

I was at the Dayton Hamvention on Saturday and Sunday, but only found one table selling a few old TI and Casio calculators in the flea market. I must have missed your booth.

[Accutron]

Well, that could've been us, depending on what day/time of day you found our booth. The best stuff usually sells pretty fast, and old TIs and Casios tend to bio-accumulate, like toxic heavy metals you can't flush from your system. If it was only a few old TIs and Casios, it wasn't us. If it was 20 sq ft of old TIs and Casios with a bunch of holes where the good stuff used to be, that was us.

Since this is a HP forum, I will specifically mention that we had no HP calculators for sale this year. I just don't find them that often in the wild, and the ones that do turn up tend to land in my own collection. On a good year, I might have one or two HPs on the table, and they vanish quickly. Every calculator guy seems to either ask if we have any HP, or complain that we don't have any HP, at which point I have to explain that I'm not some sort of mental defective who neglects HP out of spite. This year I even wore a custom-made HP 9825 t-shirt, but it must've been too esoteric because only one guy recognized it and he wasn't even a customer.

[Gene]

I remember this case study from business school. Would be interesting to find an analysis someone did while in school to compare to what actually happened.

Rockwell Calculator Business Case on calculators - PDF file

[Chasfield]

That is an interesting document, particularly the industry total US calculator sales data on page 12. I plotted this out on the attachment below.


I call this the time-to-bale-out curve - and about 100 calculator makers did just that.

Mobile phones are going the same way. Samsung beware!