


 The BT-8 is a Store/Forward Zoning Direct Paging Interface which enables staff to make public address announcements from the comfort of their own desk telephone. 
The free-standing unit acts as an interface between the analogue telephone system and the PA.
Both the BT-5 & BT-8 free standing units allow staff to dial into the Public Address (PA) system from their desk. The BT-5 & BT-8 act as a network between the telephone system and the PA and allows each individual with the opportunity to contact other members of staff or to make general announcements. This avoids contact to a busy reception/switchboard with a request to put a call out. 
To Install the units, simply connect to a PA amplifier and an available telephone extension socket (BT5) or a building’s telephone exchange (BT8). A paging announcement is available by simply dialling into the unit’s extension. 
Please note: the BT8 is not approved for direct connection to the BT network. Under general approval NS/G/23/J/100003 it may be connected to a port on a telephone switch (PABX). This unit should only be used with a switchable amplifier input.
CASE STUDY
Twinings Tea - PA and Background Music Rack Design and Build
| Description | BT-8 | 
|---|---|
| Ring voltage | 20~70v @ 17~25Hz | 
| REN value | 1.0 | 
| Mic output level | 2.5mv @ 22Ω | 
| Line output level | 0dBM 775mv @ 220Ω | 
| Time out delay | Recorded 55 sec - live 2.5 mins | 
| K break | Interruption of line current | 
| Voice operated switch | Absence of caller speaking | 
| DTMF tone | Sent from caller to terminate the call | 
| Zone select outputs | 8 x NPN open collector 40v @ 100mA max | 
| Amplifier access output | 1 x NPN open collector 40v @ 100mA max | 
| Amplifier busy input | Opto-coupled 12~30v 7mA max AC/DC | 
| Supply input | 220~240v, 50Hz, 60Hz | 
| Fuse protection | 20 x 5mm 250mA (T) | 
| Dimensions | 122(H) x 270(W) x 70(D) | 
| Weight (Net) | 3.00kg | 
| Weight (Gross) | 3.45kg |