GSM-4S SATEL
3
Figure 1. Hookup of the module to telephone line.
2.
L
IMITATIONS OF USE
As the mobile phones are designed for the maximum efficiency of speech conveyance,
the data compression feature which is used in them brings about distortions in the
transmitted audio signals, which may make difficult or even impossible sending modem
signals through a simulated telephone line (downloading, monitoring).
Cellular telephones make limitation in using the remote control function by DTMF signals.
Not every type of cellular telephone can generate the proper form of these signals. Some
models of cellular telephone have a special function permitting the DTMF control – in such
case, this special function is to be activated.
The function of remote control by DTMF signals are always available from a traditional,
stationary telephone set. The only limitations in this case can result from the quality of
telephone cables and the telephone signal level, which reaches the module.
3.
D
ESCRIPTION OF THE MODULE
THE MODULE’S TERMINALS:
TIP, RING – public exchange telephone line (subscriber’s line)
LINE
– jack for public exchange telephone line
T-1,
R-1 – extension telephone line (connection to the alarm control panel or to
a telephone set)
