Ferrograph Series 6 Tape Recorder

Ferrograph Series 6 Tape Recorder

Purchased by Derek Slater in 1967, this piece of equipment was used by Slater and Geoff Perry for the Kettering Satellite Tracking Group as part of their tracking of Soviet space activity.

Slater and Perry worked at the Kettering Grammar School together and shared an interest in space. They used borrowed and inexpensive equipment to teach their students how to track satellites. In the process of doing this, the Kettering Satellite Tracking Group was born - which in turn led to the discovery and announcement of a secret Soviet launch site at Plesetsk, securing the Group worldwide media attention.

The Ferrograph Tape Recorder was used by the Group to make high quality recordings of transmissions from early American weather satellites.

Creation of a picture involved recording an audio signal from a weather satellite onto the Ferrograph. This signal was played back through an electronic circuit to an oscilloscope (a machine that displayed it as an image scan – one line at a time). This was in turn photographed by a film camera on a long exposure setting, eventually producing an image of the Earth and its cloud cover.