Siemens MUSIC Pro - Manual (Page 37)

Pro Dir
37
Telecoil
The telecoil is intended for telephone conversations and for
using induction loops, e.g. in churches, theaters or lecture
rooms. In order to be able to use the telephone coil, your
telephone also must be suitable for hearing instruments and
emit an adequate magnetic field. It is mostly older telephones
which meet these requirements.
Unfortunately, modern phones, particularly cordless telephones
and mobile phones, do NOT all emit a magnetic field. In these
cases we recommend that you use the normal hearing programs
for telephone conversations (see also pages 53/54).