After introducing in 1968 the remarkable programmable calculator HP-9100A, which is probably the first device in the world, called "personal computer", HP released newer, more advanced systems to replace the aging and limited HP-9100A. These include the HP-9810A in 1971, HP-9820A and the HP-9830A in 1972.
HP preferred to call its power enough machines "calculators", not "computers". HP cofounder William Hewlett described the earlier HP-9100A: If we had called it a computer, it would have been rejected by our customer's computer gurus because it didn't look like an IBM. We, therefore, decided to call it a calculator and all such nonsense disappeared.
The attractive and portable HP-9830A (see the lower photo) is considered as one of the very first desktop computer (it was the earliest all-in-one machine that you plugged into a wall outlet and could enter BASIC language programs) systems ever because it includes everything to fulfill that title:
· A standard QWERTY keyboard for data and text entry
· An alphanumeric display (single line, 32 character red LED)
· A BASIC programming language (an existing, standard computer language)
· A method to load and store programs and data (a built-in cassette tape drive, later, mass storage was available via the HP 9800 Mass Memory Subsystem.)
Hewlett-Packard 9830A Desktop Calculator (© www.hpmuseum.org)
The HP-9830A is pretty big and heavy (20kg), but it also very expandable with many options. On the back there are four external slots to interface with printer, plotters, digitizers, and other I/O devices. There are also three internal and five external slots to install ROM modules for additional capacity and peripheral control. Each ROM module, costing about $485, is limited to 2K of data.
The 9830 featured a standard read/write memory of 4K bytes, expandable to 16K bytes. The built-in BASIC language compiler which provides an additional 16K bytes of hard-wired memory.
The built-in cassette drive with tape length 90 m can be operated using control keys on the keyboard, or under computer program control, and holds up to 64K of data, with search bidirectional speed of 660 mm/sec, and read/write speed of 250 mm/sec (347 bytes/sec).
The optional HP-9866A printer (see below a HP-9830A with a HP-9866A) is a full page-width, high speed, thermal line-printer capable of printing with incredibly high speed up to 240 lines per minute with 80 characters per line. Its thermal print is a full 80 characters wide, and it doesn't even move while printing. It prints one row of dots, the full page wide, all at once. The paper scrolls while printing to complete the characters.
HP 9830A with an HP 9866 printer on top (© www.hpmuseum.org)