Maker's Name: 
CSIR Radiophysics Laboratory Workshops
Where made: 
Where used: 
UQ research Labs
circa 1947

Location:  in the large glass case S44 at the right hand end of the back wall.

Built by CSIR Radiophysics Laboratory workshops to design of F.W. Wood and A.J. Higgs

From 1940 Hugh Webster and Arnold Reimann were seconded to the Radiophysics Division of the CSIR to do secret work on radar, returning in 1945. Meanwhile, the department had become involved in studies of the ionosphere, a part of the upper atmosphere where clouds of free electrons reflect radio waves back to earth, allowing long distance  wireless communication using ‘short wave’ frequencies..  Measurements made with an ionosonde  (a device which transmits pulses of radio waves upwards and measures the times and strengths of reflections) were used to forecast the best frequencies to use for communication during military operations.  In 1947 the original ionosonde was replaced by this one, designed during the war and built in Sydney. It was used first at Lambert Road and then for many years at a field station on the Moggil ‘farm’, as ionospheric physics became the major research area within the department. In this machine, the transmitter and receiver frequencies were swept in synchrony by the system of shafts and cams at the top from 1 to 7 MHz and the received pulses were displayed on a cathode ray tube and recorded on 35mm film. The signals were measured from the developed film.

In the 1970s, a new field station was built on Bribie Island and this instrument was abandoned. It was collected for the museum from the Moggil Farm after many years of disuse. Many sections had been bypassed and replaced by solid state electronics, so it had a sort of ‘heart-lung machine’ alongside which was not collected. There was literally a rat's nest in the lower section. Some parts of the frame were cleaned and repainted but much conservation work remains to be done.

This item is part of the UQ Physics Museum ‘100 Years of Physics at UQ’ Tour
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