By Mark Nobes, chief editor

Join me as I take a look back at a selection of old, vintage, retro calculators. - just what do you call them? Actually,  I'm not sure whether you can call an electronic calculator "vintage" just yet (that term makes me feel even older than I already am!) but I've had a lot of fun locating some wonderful photos of these classic, and not so classic machines.

The video clip above features a demo of an old Casio Personal Mini calculator.
HP Calculators
Old Hewlett Packard calculators - HP-11C, HP-25, HP-12C, HP-16C, HP 42s. Creative Commons Photo by AJMexico.

The HP-11c was a programmable scientific calculator introduced in 1981 and costing $135 in the U.S. The 16c was launched a year later in 1982 (also costing $135) as a programmable computer science calculator.
HP 12c Platinum Financial Calculator

HP 12c Platinum financial calculator

The HP-12c was a programmable financial calculator launched in 1981 for $135.

Vintage 1976 Texas Instruments TI-30 LED calculator with box

Texas Instruments TI-30 calculator with LED display (1976)

Texas Instruments TI-2550. Photo by Curtis Perry
During the 1970s Texas Instruments were producing a range of electronic goods including LED watches, digital clocks, calculators and the Speak & Spell.
Commodore PR-100 Calculator
Photo: Commodore PI-100 programmable calculator (1978). Photo by D. Meyer
Before producing computers, Commodore had a successful line of calculators in the 70s, but faced stiff competition from Texas Instruments who, in 1975, decided to not just supply calculator components, but build them, too.
Unicom 141P Printing Calculator
Built by Busicom Corp in Japan, the Unicom 141P printing calculator sold for $695 during it's first year of production in 1972.
Sharp PC-1403 Pocket Computer
Introduced in 1986, the Sharp PC-1403 Pocket Computer replaced the PC-1401. It featured a monochrome, one line LCD dot matrix display and unstructured BASIC programming language. The PC-1402 also had the luxury of an integrated speaker (which gave out a simple 4khz beep) and a wheel to adjust the contrast.
HP35 scientific calculator by Hewlett Packard
The HP-35 by Hewlett Packard was the first hand-held calculator in the World to feature trigonometric and exponential functions (it was a scientific calculator) and cost a whopping $395. It was produced between 1972 and 1975. It's battery life was short, though, lasting around 3 hours due to the power-sucking LED display. The HP-45 was introduced in 1973 and featured extra functions such as a timer, although it wasn't very accurate. Image by Seth Morabito
TI-81 Graphing Calculator by Texas Instruments
The TI-81 was Texas Instruments first graphing calculator. Launched in 1990, it featured a Zilog Z80 processor and a 96 x 64 pixel display. However, the processor was slow and ran at only 2mhz. The newer TI-82 (launched in 1993) ran at 6mhz. Photo by CalcVids
Casio FX-7000G Graphing Calculator
The Casio FX-7000G was built between 1985 and 1988 and was the first commercially available graphing calculator in the world. It had 82 scientific functions and included a programming mode featuring 422 bytes of memory. Photo is in the Public Domain.
Adler 81 S calculator from the mid 1970s
Adler 81S Pocket Calculator from the mid 1970s. Photo by NJR ZA
Elektronika MK-52 programmable calculator
The Elektronika MK-52 programmable calculator was built between 1982 and 1992 in the Soviet Union. The MK-52 included an Electrically Erasable Programmable Read-Only Memory (EEPROM) module for memory
Sinclair President Calculator 1978
The Sinclair President calculator which was launched in 1978. It was designed in the UK by Sinclair Research Ltd and built in Hong Kong. Photo by snowmanradio
Casio FR-2650T Printing Calculator
A recent Casio FR-2650T Printing Calculator