The accompanying article is based on a lecture delivered before a Join
t Meeting of the Association of Supervisory Electrical Engineers and t
he Institution of Engineers in Charge, at Magnet House, Kingsway, Lond
on, on November 24th, 1936. The author gives an elementary description
of the principal technical methods by which modern high definition tr
ansmission and reception is accomplished. The scope of the subject is
so wide that it must be left to future articles to elaborate theoretic
al and practical detail.