Telephonology

The great feature about the telephones and switchboards offered by this company was their simplicity of construction and ease of operation. They are especially built to be installed by people who have very little knowledge of telephonology, and when installed may be kept in perfect working order without the aid of an expert engineer.

Source: wiktionary

[…]which telephonology is based; it describes the various telephone systems, the construction of lines and the locating and remedy of telephone troubles.

Source: wiktionary

(b) Physics 4c which has previously dealt with the theory of internal combustion engines, automobiles and farm lighting plants, was changed to a course in Telephonology this year to meet the needs of the forestry “rangers.”

Source: wiktionary

‘Telephony—A Detailed Exposition of the Telephone System of the British Post Office. Volume 1, Manual Switching and Line Plant.’ The title itself is a fairly complete account of the scope of the work but the first paragraph of the Review still further explains the scope and in the addition suggested for the title page showing that the book is a combination of text-book and reference book detailing all apparatus within the scope of the volume and suitable for all engaged in Telephonology other than elementary students knowing nothing whatever of the subject.

Source: wiktionary