Radio-Electronics Aug 1949 - p. 59

The war on interference
You may recall that I've told you already how we in Britain are tackling the problem of
man-made interference with radio and television reception by making it illegal to operate an
unsuppressed factory machine, domestic electrical appliance, or automobile.  In Switzerland
they're dealing with some of the main causes of interference in another way. Switzerland is,
in proportion to its size and its population, perhaps the most completely electrified country
in the world today.  Thanks to its vast resources of waterpower, even small villages and
outlying farms have electric mains supplies.  No steam locomotive runs on its railways and it
has a vast mileage of electric street-car systems.  Some of the street cars operate over
interurban systems of considerable extent.  With cheap electric power available everywhere you
can imagine that radio listeners (there are no televiewers yet) complain bitterly of the
effects of man-made static.  They have to pay for licenses to use radios and they're not a bit
pleased when a fine selection of "noises offstage" makes a classical concert sound like a
feature program concerning a large boiler factory.

The license fees are collected by the government Posts and Telegraphs Department, which has
recently decided to spend a considerable percentage of this income on static suppression at
source.  To accomplish this will certainly cost a tidy sum, for, to take transport alone, both
the railways and the street car systems use overhead conducting wires with spring-loaded sweep
contactors on locomotives and cars.  At every joint in the overhead wires the travelling
contactors are liable to jump, producing sparks and radiation of the kind which shock-excites
antennas over a considerable area.  The problem is a pretty big one, you'll agree, and the
Swiss are to be congratulated on getting down to it in this practical way.