Illumination; Arrangements for improving the visibility of characters on dials

Introduced: September 1968

Last revised: January 2006

Full Title

Substation equipment, e.g. for use by subscribers > Constructional features of telephone sets > Illumination; Arrangements for improving the visibility of characters on dials

Classification Context

Section:: ELECTRICITY
Class:: ELECTRIC COMMUNICATION TECHNIQUE
Subclass:: TELEPHONIC COMMUNICATION