In 1951 the Mi51 was the smallest portable recording device in the world. It was a popular device and was used for surveillance by private, government and other agencies around the world. The control buttons are designed for easy operation when the device is concealed under clothing. The Mi51 came with a range of aatractive accessories including a wrist watch microphone and telephone tapping attachment.

Information contained on object

The origins of the postal security branch go back to the appointment of mail guards to travel with coaches (and later trains) to the gold fields. The first postal detective was appointed in 1877 and the branch grew gradually until renamed the Inquiry Section by 1934. In 1983 Australia Post employed 60 investigation officers on a nationwide basis of whom 23 were based in NSW & the ACT. In 1974 the postal security branch covered motor vehicle accidents, revenue loss from public telephones, and general investigations. These objects were used from the 1950s by investigation officers in the course of these duties. (See notes supplied by NSW Historical Section)

Recording device, Minifon Mi51, bakelite / metal / electronical components, used by Australia Post, Australia / Germany, 1951-1953

Cream coloured Bakelite sound recorder.

Made: Minifon; ; 1951 - 1953

Used: Australia Post;

insc. in white paint "13"
gold lettering on front l.r. "minifon"

98/2/1-3/1

1951 - 1953

176 mm

110 mm

42 mm