BT are currently planning the next generation of telephnone network (21CN) and when this is implimented, starting in November 2006, there is expected to be some digital communicators that may not work correctly , or not at all. We are currently in discussions with BT to try to gauge the extent of this issue. BT have released an overview of the issue and there is a downloadable file of the report on this website.

 Test Results

Tests have been carried out with BT in Martelsham to try to ascertain the impact of the introduction of the 21CN Network with digital communicators. A selection of communicators were tested from Honeywell,Coopers and CSL.

The tests carried out simulated delays in transmission up to 300mS and beyond to ensure they worked to the maximum specified by BT. The result of the tests were encouraging with most units being able to work properly up to the maximum delay.

True network tests were not carried out due to the fact that we could only simulate line lengths of 10 Km therefore more tests will be needed to asses the impact of the attenuation created by longer lines.

We will keep you posted when more information becomes available.