Storage of abbreviated cell numbers in centrally controlled telephone e - uses times switching device after selecting characteristic digit, followed by abbreviated number, for optically display

摘要

The storage of an individual complete call number takes place by selecting a first digit, characteristic for desired condition, followed by selection of a given code sign, and final selection of the complete number. The cancelling of a stored complete number is carried out by selection of a desired cancelling code digit and by following selection of the corresponding abbreviated call number. After selection of the first code digit and the following selection of the abbreviated call number, a timing circuit becomes effective giving an optical display of the stored complete call number for the maximum time, required for the selection of any arbitrary complete call number to e stored. After this time period the circuit triggers the cancellation of the stored complete call numbers, if the start of the following selection of a different complete call number did not take place.