Description:
- Object ID: ALSA 2013.05.01
- Made by: Hewlett Packard
- Model: 3805A
- Serial Number: 1440A03041
- Date Made: Circa 1970’s.
- Approximate size: 33cm length, 26 cm width, 15 cm height.
- Accessories: Orange carrying case, lens cover, Ni-Cad Battery Pack model11441A, (Marked NO GOOD), Battery cable, Two coil bound operating manuals, one in poor condition. two 11/2 A – 240 V fuses in plastic bag, service information card.
- Condition: Fair
Commentary:
The Hewlett-Packard Model 3805A distance meter used an infrared light beam to measure distances. It is capable of measuring distances up to 1600 metres with a triple prism during ideal conditions. It has an accuracy of +/-(.02 feet+.01 ft per 1000feet).within a temperature range of +15F to 105F. The infrared light beam is transmitted to one to three prism reflectors, and returned to the instrument. The more reflectors the greater the distance that can be measured. The transmitter lens and the receiver lens are located at the front of the Instrument. The transmittter lens is located inside the receiver lens. A sighting telescope is located at the top of the instrument.
From a Hewlett Packard ad in the publication California Surveyor, Issue No. 36, ” 1975 about the HP 3805 ” . . . it just happens to be our most popular distance meter. Probably because it has a built-in computer that averages 3,000 measurements in six seconds and a built-in battery that eliminates awkward cables and a display that lets you read distance in either feet or meters at the flip of a switch.”
It was used by Gordon Haggerty for legal and engineering surveys in Alberta.
Source of Object: Donated by Gordon Haggerty ALS.
Notes: This is the only HP3805A in the Societies collection.
References: MURPHY, JAMES SMITH. Electronics Based Innovation In A Niche Market: Distances Measured By The Speed Of Light: Murphy. Electronics Based Innovations. Operating Manual and a Brochure “Hewlett Packard Model 3805A Distance Meter” in AGHS hard copy file.
Description by: Entered by Ed Titanich, October 5, 2024. Gordon Olsson November 26, 2025.