TELLUROMETER

South Africa, Preto · 1979-02-12

Official

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front

Cachet: The cachet shows a large blue globe rendered in a grid of latitude and longitude lines, with a technical drafting compass positioned above it, one leg resting on the globe's surface as if taking a measurement. The design is simple and technical, evoking surveying and precise measurement rather than decoration. Curving around the globe the words "25th Anniversary of the Invention of the Tellurometer" appear in English, with the Afrikaans equivalent "25e Herdenking van die Uitvinding van die Tellurometer" following the same curve beneath it.

Info card

TELLUROMETER South Africa has played a leading role in radio distance measurement ever since the invention of the Tellurometer system in 1954 — so much so that she remains the world's major producer of this type of equipment, with something like 80 per cent of the world market. Geodetic surveyors had for many years felt the need for portable equipment capable of measuring distances up to 50 km to within one part in 100 000, but despite the expenditure of large sums of money elsewhere in the world in repeated attempts to develop such equipment no success had yet been achieved. South Africa's Council for Scientific and Industrial Research (CSIR) directed its attention to the problem in 1954. The project was allocated to Dr T.L. Wadley of the National Institute for Telecommunications Research, who in a matter of months produced the Tellurometer system which was to have so profound an effect on the survey world. Exhaustive field tests showed that the system more than met the requirements laid down. Production was entrusted to a firm in Cape Town after patents had been sought in a large number of countries, and the first production instrument was completed in January 1957. The invention aroused immediate interest and hundreds of instruments were in use around the world by the end of that year. It was soon apparent that the availability of a cheap, light, quick and accurate means of distance measurement had virtually brought about a revolution in surveying methods. The CSIR has continued its research and development in radio distance measurement and, in collaboration with the South African producers, has brought about many improvements to the system. The most recent achievement is the development of automatic equipment with which a measurement can be completed in little more than ten seconds after setting up the instruments — a task that twenty years ago could take a month! TELLUROMETER Sedert die uitvinding van die Tellurometer-stelsel in 1954 speel Suid-Afrika in so 'n mate 'n leidende rol in radioafstandmeting dat dié land die wêreld se grootste produsent van hierdie tipe toerusting bly en sowat 80 persent van die wêreldmark het. Geodetiese opmeters het baie jare lank die behoefte gevoel aan draagbare toerusting wat afstande van 50 km tot een deel op 100 000 kan meet, maar ten spyte daarvan dat groot bedrae geld elders in die wêreld in herhaalde pogings aan die ontwikkeling van sulke toerusting bestee is, is geen welslae behaal nie. In Suid-Afrika het die Wetenskaplike en Nywerheidsnavorsingsraad (WNNR) die probleem in 1954 aangepak. Die projek is aan dr. T.L. Wadley van die Nasionale Instituut vir Telekommunikasienavorsing toevertrou en hy het binne maande die Tellurometer-stelsel geproduseer wat so 'n verreikende uitwerking op die opmeetwêreld sou hê. Volledige veldtoetse het getoon dat die stelsel die vereiste ver oortref het. Produksie is aan 'n firma in Kaapstad toevertrou nadat patente in 'n groot aantal lande verkry is en die eerste produksie-instrument is in Januarie 1957 voltooi. Die uitvinding het onmiddellik belangstelling gewek en teen die einde van dié jaar was daar reeds honderde van dié instrumente die wêreld oor in gebruik. Dit was gou duidelik dat die beskikbaarheid van 'n goedkoop, ligte, vinnige en akkurate manier om afstand te meet 'n omwenteling in opmeetmetodes teweeggebring het. Die WNNR het sy navorsing na en ontwikkeling van radioafstandmeting voortgesit en het in samewerking met die Suid-Afrikaanse produsente baie verbeterings in die stelsel aangebring. Die jongste prestasie is die ontwikkeling van outomatiese toerusting waarmee 'n meting in minder as tien sekondes afgehandel kan word nadat die instrumente opgestel is — iets wat twintig jaar gelede 'n maand in beslag kon neem!

Additional information

This cover is postmarked on 12 February 1979 in Pretoria. The stamp depicts the Tellurometer instrument itself alongside a portrait of Dr T.L. Wadley, the scientist at the National Institute for Telecommunications Research who developed the system in 1954. The Tellurometer solved a problem surveyors worldwide had struggled with for years, portable equipment accurate enough to measure distances up to 50 km. Within its first year of production in 1957, hundreds of units were already in use internationally, and South Africa went on to supply around 80 percent of the world market for this type of surveying equipment.

Theme: Science & Technology

Condition: FineGood condition. Minor wear or small imperfections, but overall well-presented.

Addressed: No

Signed: No

Stamp denomination: R0.15 (ZAR)

SAPO serial number: 3.12

Estimated value: ~US$0.1

This is a high-level, subjective estimate only, not a professional appraisal.