There is some bad advice or incorrect comments in some of the other posts.
The (
i) is VERY significant. It indicates that the ST585 is the ISDN variant . There are two models, one for use on the UK's analogue systems and one which operates on ISDN lines - which is not available in the UK.
You need to ensure you do not get the wrong one - although most UK suppliers will not normally stock the (i) version.
Download and read the installation guide from
here
M H C
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