The Secret Life of the Video Recorder

The principle of magnetic recording was invented by a Danish telephone engineer called Valdemar Poulsen in 1899. He used an electromagnet to record the tiny electric currents from a telephone to magnetise a steel wire. This recreated tiny currents in the electromagnet when it was replayed. All tape and video recorders still work this way.

SERIES 1:  vacuum cleaner sewing machine central heating system washing machine refrigerator television 

SERIES 2:  car internal combustion engine quartz watch   telephone radio set video recorder  

SERIES 3: fax machine lift word processor electric light photocopier the office

<< back to the secret life of machines homepage


Cartoons copyright (C) 1988-1994 Tim Hunkin. All rights reserved.
Site design copyright (C) 2002-2004 Pelham Projects Ltd. All rights reserved.
click here to contact us