How to replace the fuse: Open the fuse compartment with a screwdriver and replace the fuse
and fuse cover.
This equipment should be used on PSTN lines requiring 2-wire Loop calling unguarded
clearing with Loop Disconnect or DTMF address signalling.
The equipment must be connected to direct exchange lines and a payphone should not be
connected as an extension.
999 and 112 can be dialled on the apparatus after accessing the Exchange line for the purpose
of making outgoing calls to the BT emergency (999) and (112) service.
During dialling, this apparatus may tinkle the bells of other telephones using the same line. This
is not a fault and we advise you not to call the Fault Repair Service.