The desk top calculator, introduced at a special press conference in New York City on March 11, ranks as one of the most exciting instruments developed by the company in its 29-year history. The following interview with HP Presi­dent Bill Hewlett explores some of the more significant aspects of the new instrument and its impact on the marketplace.

MEASURE: Turning first to the technology of the desk top calculator, what are a few of the more important features of the instrument that set it apart from currently available calculators?

MR. HEWLETT: I would say that the desk top calculator’s ease of operation, its wide range of standard mathematical functions available at the fingertip, its capability to accept programming either manually or by magnetic card, and the fact that it is designed to operate with auxiliary equip­ment such as printers and plotters, are certainly some of its outstanding features.

MEASURE: A look at the keyboard shows that the desk top calculator is capable of some highly complex perform­ance with a minimum of effort by the operator. Can you give us an example of a problem that would illustrate this, and some indication of the time required to solve the problem using the 9100A?

MR. HEWLETT: One good example would be found in surveying. Let’s suppose that a surveyor is trying to measure an irregularly-shaped plot of land. It will he necessary for him to make a number of sightings to get around the plot. His measurements will be in the form of angles and dis­tances, called polar coordinates. He needs to convert these measurements into rectangular coordinates, that is, so many feet north or south and so many feet east or west. For every readout, therefore, he must use a set of trig tables with lots of multiplying to obtain the new rectangular coordinates of the point – a tedious and time consuming job. With the 9100A, all he needs to do is simply enter his angle, then his distance, and press the Polar to Rectangular key. The answer in rectangular coordinate appears at once. Another button on the keyboard will let him add each of these calculations to the previous calculations. His “closure” error is then immediately available at the touch of another key. A simple program will also provide the area enclosed by the traverse.

… we wanted to teach the calculator routines so that it would never forget …

MEASURE: We understand that the desk top calculator doesn’t use integrated circuits. Could you explain the type of circuitry it does have, and some of the reasoning that led to this type of design?

MR. HEWLETT: We wanted to build in a lot of routines, such as changing from Polar to Rectangular coordinate mentioned above, and we wanted to use a very special type of circuitry that would teach the calculator these routines so that it would never forget. Such a device is called a Read Only Memory. The 9100A’s memory contains over 32,000 bits of information. We achieved a Memory of this capa­bility through the use of very complex multilayer circuit boards. The board consisted of 16 separate layers all lam­inated together, each with the necessary geometric design corresponding to the information desired to be stored on them. Transistors appeared to be the most effective method of coupling into and out of the Read Only Memory.

MEASURE: In the area of marketing, what is HP’s estimate concerning the size of the calculator market?

MR. HEWLETT: The calculator market is in a period of substantial expansion, so it’s hard to pin a specific figure on its present size. However, there’s no question but that this market is a sizable one.

MEASURE: Would you expect that our electronic cus­tomers will make up the bulk of calculator sales, or will we find that we are dealing with a new profile of technical personnel?

… traditional customers will account for only about a quarter of the market …

MR. HEWLETT: A preliminary survey indicates that our traditional customers will account for only about a quarter of the market. Other major customer areas will include such fields as mechanical engineering, civil engineering, chemistry, and physics. The calculator will also have strong appli­cation in the field of statistics and general business use. The great flexibility of the calculator means that it will find wide use in many diversified fields, related only by their mathe­matical computational needs.

MEASURE: Will this result in any changes in our field sales organizations from the standpoint of numbers of people or specialized personnel?

MR. HEWLETT: We feel sure that we are going to have to have field sales specialists who are thoroughly conversant with the power and general flexibility of the calculator, and who can call on a wide, diversified group of customers.

MEASURE: What sort of acceptance do you think the cal­culator will get in international markets?

MR. HEWLETT: I would expect that the calculator would find very great acceptance in the international market, for it can perform many functions that a more traditional computer might perform, but at far less expense.

MEASURE: The Loveland Division will manufacture the instrument. What effect, if any, will this have on Loveland’s production facilities and its employment?

MR. HEWLETT: There isn’t much I can say about the employment level at this time, since that will depend almost entirely on the volume of sales. With regard to production facilities, it was necessary to introduce special facilities at Loveland to manufacture and check out the calculator. One example is a special printed circuit facility to make the Read Only Memory. In addition, a considerable amount of auto­mated equipment is being installed to give final checkout of the instruments.

MEASURE: When will the first units be available for delivery to customers?

MR HEWLETT: The estimate now is that instruments will be available for delivery in late summer.

… it was designed with every consideration given to the logic of layout and ease of operation …

MEASURE: Finally, we understand that the overall ap­proach to the calculator was unique, and accounts for the instrument’s flexibility and capability. What was this approach?

MR. HEWLETT: Unlike other calculators, the 9100A was designed from the outside in, not vice versa. By this I mean that the controlling design factors were set at the interface between the calculator and the operator. It was designed with every consideration given to the logic of layout and ease of operation as far as the user is concerned. Subject then to this constraint, the designers had to come up with the necessary internal circuitry to meet these requirements. I’m happy to say this rather formidable challenge was met.

(From HP Measure, March 1968)