| 摘要 |
<p>From the intermediary coupling jack between the telephone and the wall jack runs a cable, which is 5,10 or 20 metres in length, to a box with the domestic sound equipment. The loudspeaker cables are connected, together with the stereo, via the box. The equipment can include one or more loudspeaker cut-outs or dampers, but this usually requires one pair of cut-outs with load over the loudspeaker inputs so that the final stage of the amplifier is protected. The installation enables the line current to be monitored via the telephone line when the handset is raised for use in making a call and also when the telephone rings. With the current established the volume of acoustic equipment is regulated. @(Provisional basic advised week 91/02)@ @(4pp Dwg.No. 1/1)@.</p> |
