
E F - 7 0 1 M I N T E R F A C E
1 - 3
Figure 1-1: Connecting a party-line channel to a Matrix intercom
CONVERTING A PARTY-LINE CHANNEL TO 4-WIRE AUDIO
The EF-701M Interface converts a channel of standard or TW party line to 4-wire audio
and, at the same time, converts a DC-voltage call signal or 20-kHz call signal to RS-422
data. This 4-wire audio and RS-422 data can then be sent to a fiber-optic converter
(modem); over copper, unshielded twisted-pair (UTP) cable such as Category 3, 5, or
above; or it can simply be used as an excellent stand alone 2-wire to 4-wire converter. In
most cases though, EF-701M units will be used in pairs, because once the signal is
3
3
= Male 3-Pin XLR
= Female 3-Pin XLR
Party-Line Intercom
EF-701M
3
3
3
3
RJ-45
RJ-45
Matrix