A - 9 APPENDIX A
Using extension telephones (For U.K. only)It may be that your premise s are already wired with parallel extension
telephones, or you inte nd to add extension telephones to your line,
in addition to your machine. While the simplest arrangement is
straightforward parallel connection, there are some reasons as to
why this arrangement will cause unsatisfactory service, the most
obvious of which is inadvertent interruption of a facsimile
transmission by someone picking up an extens ion telephone in ord er
to make an outgoing call. Additionally, Fax receive code may not
operate reliably in such a simple configuration.
This machine may also be set to make a delayed transmission (i.e. a
transmission at a pre-set time). This pre-set job may coincide with
someone picking up an extension handset.
Such problems can easily be eliminated however, if you arrange
modification of your ext ension wiring circuit, such th at extension
devices are connected “down stream” of your machine, in a
master/slave configur ation (see fig. 2 on next page). In suc h a
configuration, this mach ine can always detect whether a tele phone
is in use, thus it will not attempt to seize the line during that time. This
is known as “telep hone off-hook detection .”
The inadvisable configu ration is shown in figure 1 o n the next page,
and the recommended mast er/slave configuration i s shown in figure
2.
This new connection configuration can be a rranged by contacting
BT, Kingston upon Hull Telecomm unications, your PABX maintainer
or a qualified telephone installation company as appropriate. Simply
explained, the extension telephone circuit should be terminated on a
normal modular plug (BT 431A style), which in turn should be
inserted into the modul ar socket of the white “T”-shaped connector
provided as part of the line cord assembly.