HP Voyager series: Difference between revisions

== Design ==

In an attempt at standardizing the product lineup, HP designed all the Voyagers around the same chasis, which was a two-piece plastic design, secured using four screws hidden under the rubber feets. The front plate housed the keyboard legend, the display acryllic window and the faceplate which had an indent for a HP logo and name plaque. These were all secured using glue. The rear plate held a glued-on painted metallic plate with additional information, the battery compartment holding three LR/SR44 cells, as well as the rubber feets. Internally the PCB is secured to the front plate using heat-stakes, with up to three surface mount ICs soldered to the backside. The LCD display is held by eight bent metallic feet to the PCB, and is electrically connected to the front side of the PCB via elastomeric connector (otherwise known as ZEBRA connectors).  

One significant design change was the vertical and horizontal rearranging of the four function keys, breaking from the tradition established by HP35 in 1972. Due to the great commercial success of the Voyagers, this new arrangement was subsequently inherited by later Pioneers and beyond, a decision that to this day remains highly controversial within the HP community.  <syntaxhighlight lang="text">

</syntaxhighlight>Since ROM space was less of a constraint by that time, HP starting from the HP-91 implemented more nuianced algorithm for certain classes of operations to make them exact, for example with small integers raised to small integer exponents, and special trigonometry values. Accuracy is thus rather nuianced: the Voyagers did not employ persistent guard digits, meaning that what the user see is what is actually stored in the calculator. Internally the Voyagers calculates with 13 digits intermediary results, but immediately rounds them off to 10 digits upon finishing. Built in functions are guaranteed to have at worse the wrong 9th digit, and usually to no more than 1 off by the last digit. (On the HP 15C, for complex operations the accuracy is specified with regard to the complex value formed by real and imaginary parts, which means that each individual component can have error as large as the fourth significant digit.)   

== See also ==

* [[HP Pioneer series]]