CT1 stands for
Cordless telephone generation 1 and is an analog
cordless telephone standard that was standardized by the
European Conference of Postal and Telecommunications Administrations (CEPT) in 1984 and deployed in eleven European countries. The initial set of frequencies provided for a set 40 duplex channels using 25 kHz separation, with the phones transmitting in the 914-915 MHz band and the base stations in the 959-960 MHz band. These frequencies overlap with those used by channels 120-124 on
GSM cellular phones and thus these original frequencies have been withdrawn from use for cordless phones in the countries that originally authorized them.