General Information

Serial #

1623A04708

Part Number

1

Total Parts

5

AKA

Calculator

Patents

N/A

General Description

Synthetic casing, keys, cord covering, windows and parts/ Metal working parts/ Rubber? feet

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

34.5 cm

Width

34.4 cm

Height

10.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Mathematics

Category

Calculating devices

Sub-Category

N/A

Manufacturer

AKA

Hewlett Packard

Country

United States of America

State/Province

Unknown

City

Unknown

Context

Country

Canada

State/Province

Ontario

Period

circa 1978 +

Canada

An instrument used at the David Dunlap Observatory at the University of Toronto, one of Canada's most important astronomical observatories. The David Dunlap Observatory opened in 1935 as the result of a bequest from the wife of David Dunlap. The telescope was a 74 inch (188 cm) reflector built by Grubb Parsons of Newcastle-upon-Tyne in England. The 74 inch was then the largest telescope in Canada (surpassing the 72 inch telescope of the Dominion Astrophysical Observatory in Victoria) and became the second largest in the world after the 100 inch Hooker Telescope of the Mt. Wilson Observatory outside Los Angeles. DDO's reputation grew and following WWII, it began to graduate most of the astronomers produced in Canada with University of Western Ontario far behind. Beginning in the 1960s a number of other astronomy departments were created but UofT/DDO held its place, a position it probably still holds. The DDO had a good technical staff which gave them an advantage and, with most of the 1940s to early 1970s top astronomers coming from UofT, grants from NRC and then ENSERC were almost guaranteed and allowed UofT's top astronomers -- Hogg, van den Berg, Fernie, Bolton, Kamper, Martin, etc. to acquire or build some of the best equipment available in university observatories. For optical observatories, only the DAO had technical staff and budgets that surpassed those of DDO. In 2007, citing increasing light pollution, the University of Toronto announced plans to sell the Observatory property. In June 2008, it was sold to Corsica Development Inc., a subsidiary of Metrus Development Inc. and the Observatory was closed. In 2009 the Observatory buildings and 80% of the site were designated a cultural heritage landscape. Also in 2009 Corsica and the Royal Astronomical Society of Canada, Toronto Centre announced an agreement allowing the RASC to provide public education and outreach programs at the observatory, and to operate the 188 cm telescope.

Function

Generally, a device which electronically performs mathematical calculations. This example was used as a controller for a measuring engine used at an astronomical observatory.

Technical

An example of accessory equipment used with an astronomical analytical instrument. This device is an electronic calculator from the late 1970's, used a controller for the Grant Spectrum Line Measuring Comparator 2008.0177. That instrument was used to measure spectral lines from plates, largely, though not exclusively, taken with the spectrographs on the 74 inch telescope at the David Dunlop Observatory.

Area Notes

Unknown

Details

Markings

Grey lettering on front and back reads 'HEWLETT PACKARD 9815A'/ Plate on underside reads 'SERIAL No/ 1623A04708/ HEWLETT PACKARD/ MADE IN U.S.A.'/ Label on underside reads 'hp [logo] HEWLETT-PACKARD/ WARRANTY TYPE A/ DIV. 4000 TERM/MO. 03/ SHIPPED 12/1/78'/ Gold, black and white lettering for control functions/ Yellow and black applique lettering on front reads '4K' and '6'

Missing

Power cord

Finish

Grey casing with brown front and back/ Brown, gold and buff coloured keys with white and black lettering/ Colourless, transparent windows/ Plated parts/ Black feet

Decoration

N/A