Welcome to Digital Systems Products Ltd

Europes leading manufacturer of ISDN modems / ISDN Terminal Adapters.


We have over 20 years experience in new installations and replacing your obsolete ISDN from Eicon, Chiron, WebwayOne, Sonix Volante, AVM Fritz, BT Speedway, Controlware Citam, Zyxel Omni-Net, Sarian, Linxspeed, Multitech etc.

New - Replace your obsolete CAPI ISDN card and driver software (eg Speedway,Fritz)!

CTA now includes support for remote configuration of Avaya, Siemens, Panasonic, NEC and Via switchboards

The CTA ISDN modem - robust, packed with features and with free technical support and updates !

Site last updated 16/3/2017 DSP ltd 2017