Changes

Unknown if Schneider BTX module for the device includes the actual modem built-inCPC.The hardware design is based on a universal BTX decoder made by Siemens.. probably, one needed It is connected to rent the CPC's expansion port and additionally hooked in between computer and monitor. The module must also be connected to a BTX modem from with a D-BT 03 port. These modems were provided by the Deutsche Bundespost separatelyPost and had to be returned after use, because the BTX subscriber ID was hard-coded within the device.

BTX (Bildschirmtext, translated as Screentext) has been a german German service, allowing to transfer data via telephone line. In the 8bit era, the Deutsche Bundespost (german German postal service) still owned the monopoly for telecommunications in germanyGermany, so the only (legal) way to transmit electronic data via telephone line has been to use their BTX service. The service was ultimatively suspended in 2007. Beginning in late 2019, some work has begun to revive parts of the BTX service. There are [https://btx-museum.de/2020/02/29/der-neue-dbt-03-emulator/ emulators providing D-BT 03 ports], and some BTX pages were [https://www.heise.de/newsticker/meldung/36C3-Congress-wie-1984-mit-BTX-und-Originalarchiven-4624507.html restored by feeding recordings of original modem sessions to software demodulators].