Calculators

The following calculators have been owned and used by Hans Sundgren.

HP 17B with infrared printer
Technical data
  • 22x2 digits, LCD
  • 37 keys
  • 6 kB RAM
  • 148 x 80 x 15 mm, 120 g
  • Power consumption: ??? mA
  • 3x1.5 V xxx cells
  • No external power
  • Printer connection via IR
Documents

pdf None

Xxx 1990

Hans gets this calculator as part of a work compensation program. He selects the calculator himself and wants an economical type of calculator with possibility to program any problem. This calculator has also an IR-connected printer.

Good
  • Very inutitive, easy to program
  • Robust design
Bad
  • The printer has a high power consumtion
  • ???

End of life 19xx

In XXX 199x the calculator is stolen when is is stored in a breifcase in the car parked in Djurgården, Stockholm. The printer is left in Västerås.

Commodore SR4148R
Technical data
  • 10 digits, 7-segment, red LED
  • 48 keys
  • 2 storage registers
  • 151 x 79 x 36 mm, 158 g
  • Power consumption: 400 mA
  • 3xAA NiCd accumulators
  • 6 V DC external adapter
Documents

pdf None

August 1977

When entering the final 4'th year of his engineering studies, calculators were now accepted. So Hans buys a scientific calculator with R/P functions needed for his last years study of high voltage electrical engineering.

weblink SR4148R on Vintage Technology

Good
  • All possible functions included
  • R/P included, which was not the case with other calculators.
Bad
  • High power consumtion, required AC voltage after some time.
  • Buttons without "click".

 

Sinclair Cambridge
Technical data
  • xxx
Documents

pdf None

Xxx 197x

Hans read the magazine "Radio och Television" and sees an ad describing the Sinclair Cambridge calculator from Great Britain.

Good
  • A special K-key simplifies constant calculations.
  • Small, quite inexpensive.
Bad
  • Not 100% correct calculations. A correct result of 2.0 could be presented as 1.9999999.
  • ???

 

Slide ruler
Technical data
  • xxx
Documents

pdf None

Xxx 197x

Calculators are not accepted when Hans starts the secondary school, studying to be an engineer. So Hans is forced to learn how to use a slide ruler.

Good
  • Requires no batteries or power supply.
  • Gives the user a good mathematical understanding.
Bad
  • The result is givien in only a few decimals and the number of zeros has to be manually "calculated".
  • Not suitable for addition and subtraction, even though it is theoretical possible.