TIPTEL Ergophone 307 Operating Instructions Manual page 8

Socket with only one slot
1 Insert the power supply unit with the small connector into the
"POWER" jack and then insert the power supply unit into a 230V
wall socket.
2 Disconnect the existing telephone cable from the telephone and
insert the free connector into the "LINE" jack.
3 Insert the connection cable provided into the telephone with
one connector and into the "TEL" jack with the other connector.
This connection option is recommended on the assumption that

the telephone's connections are a normal pair of telephone ca-
ble connections. This is the case if the telephone complies with
regulations TBR21 or ETSI ES 203 021. In the event that the
"earth" and "alarm" contacts are used on your telephone socket,
you must only use a two-core telephone cable.
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