Text largely copied and adapted from Alan Cordwell.

"Artemis is a short range positioning system developed by Christian Huygens Laboratorium (CHL) of the Netherlands and taken in by the Nederlands Survey Apparaturen BV (NeSA). Thus it came into the Racal-Decca sphere in stages. Operating at 9.7-9.8GHz, the system offered exceptional accuracy (0.5m range and 0.1degree azimuth) and a range of up to 30Km. The Mobile and Fixed installations consisted each of two Units, an Antenna Unit and a Control Unit; MAU, MCDU, FAU, and FCDU respectively. The transmitters had an output power of 100mW in the high setting and 3mW at low power/short range. These were the CW ratings so as the transmissions were interrupted at the modulation rates effective power was less. As it was a one-to-one package multiple users created problems for the technicians in avoiding mutual interference. These were to a large extent counteracted by extending the number of frequency pairs accessible and by the selective addressing facility.

There have been many well known versions used since the late 70’s, the Mk3 which has provided the basis for these comments, the Mk4, a development with microprocessors and slightly more user-friendly packaging the Mk 5 and the Mk 6 which is still in current production with Guidance Marine Systems."

Shown is a MkIII processing unit. When no longer usefull with the NeSA theis unit arrived in the collection of Rob Berlijn (together with a number of other instruments also in my collection). When Rob passed away to early his widow donated the objects to CT-Systems who in turn, after many years of custody donated them to the exception of a few land survey instruments which are now in the collection of Nicolas de Hilster as they are more fitting in that collection. I am very happy to be able to show these as I was afraid that they had become lost to history. Thank you Rob for your foresight!

More information:

Alan Cordwell

Guidance Marine