Voice Recording Board (VRB3)
From Zenitel Wiki
The Voice Recording Board VRB3 is a single Euro format (100 x 160 mm) PCB with facilities to accept and mix both microphone and loudspeaker signals of six user stations connected to AlphaCom ASLT ports and to present these as transformer coupled, 600 Ohm, nom. 0dBm outputs for recording by (typically) external, analogue input, multi-channel voice recording equipment.
Up to twenty VRB3 boards may be mounted within a standard 3U x 19-inch housing and each board requires a dedicated DIN41612 (a,b) 64 pin female connector with 13mm (wire wrap) pins. Input and output cable assemblies are available which simply plug onto the rack connector 13mm pins but which are free at the distant end for connection as required.
VRB3 requires 24VDC @ 20mA and should be powered from the AlphaCom exchange.
Audio input connections to VRB3 are taken from AlphaCom subscriber ‘b’ and ‘d’ wires. Mixed audio output (per subscriber) is presented on 2 wires.
VRB3 Board Connections (DIN41612, 64-way, a,b-row)
| a1, a2, b1, b2 | +24V from AlphaCom |
| a31, a32, b31, b32 | 0V from AlphaCom |
| b5 | b-wire input 1 |
| b6 | b-wire input 1 |
| b7 | b-wire input 2 |
| b8 | d-wire input 2 |
| b9 | b-wire input 3 |
| b10 | d-wire input 3 |
| b11 | b-wire input 4 |
| b12 | d-wire input 4 |
| b13 | b-wire input 5 |
| b14 | d-wire input 5 |
| b15 | b-wire input 6 |
| b16 | d-wire input 6 |
| a24, b24 | output 1 |
| a25, b25 | output 2 |
| a26, b26 | output 3 |
| a27, b27 | output 4 |
| a28, b28 | output 5 |
| a29, b29 | output 6 |