User manual ASL INTERCOM BS 15

[. . . ] The volume of the sound signal (buzzer) can be adjusted at the front panel. The BS 15 is a portable single channel user station housed in a strong ABS case. On the front panel are a Volume (listen level) control, a Talk and a Call button with LED indicators, a sidetone trimmer and a buzzer volume. By applying low noise/high speed opamps, a speech presence filter and a specially developed amplifier, communication is very comfortable even in environments with a very high background noise level. 2. 0 UNPACKING ASL has taken great care to ensure this product reaches you in flawless condition. After unpacking the unit please inspect for any physical damage to the unit, and retain the shipping carton and relevant packing materials for use should the unit need returning. [. . . ] The buzzer is activated if you press the CALL button of the BS 15 (3) or a CALL button of any other station (on the channel to which the BS 15 is connected), longer than 2 seconds. 4 User Manual BS 15 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland. 5. 0 REAR PANEL CONNECTORS 6 LINE connectors These XLR-3 connectors are for connecting the BS 15 to the intercom system. The male connector is for extending the intercom line to other user stations. 7 HEADSET connector An XLR-4 type connector for the connection of the local headset. This must have a can impedance of 200 ohms (or greater), or each minimum 400 ohms when in parallel. phones - (GND) 6. 0 INTERNAL CONTROLS MIC GAIN The mic gain can be adjusted internally by a trimmer. To decrease mic gain turn counterclockwise. - User Manual BS 15 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland. 5 7. 0 CABLING For the BASIC Series Intercom system the interconnecting cables are of the shielded two-conductor microphone cable type and the intercom line connectors are of the XLR-3 type. XLR pin 1 is connected to the shield of the cable which functions as the common return for audio and power. Since the audio signal is transferred in an unbalanced way, certain rules have to be obeyed when installing the cables of an intercom network. This is to avoid earth loops and to minimize power loss and the possible effect of electromagnetic fields. These rules are: ¼ Use high quality (multipair) cable. For interconnecting user stations, power supplies and accessories in an ASL Intercom network, use high quality shielded two-conductor (minimum 2x 0. 30 mm2) microphone cable only. In case of a two channel intercom network, use high quality microphone 'multipair' cable only, each pair consisting of two conductors (minimum 2x 0. 15 mm2) with separate shield. Use flexible single and multipair microphone cable instead of cable with solid cores, especially when the cable is subjected to bending during operation or installation. The screen of each separate microphone cable and/or the screen of each single pair in a multipair cable, should be connected to pin 1 of each XLR-3 connector. Do not connect this cable screen to the metal housing of the connector or to metal wall boxes (outlets). Cable trunks, connection boxes and overall multipair cable screen to clean earth. Metal cable trunks, metal connection boxes and overall multipair cable screen should be interconnected and, at one point (the 'central earthing point') in the intercom network only, be connected to a clean earth or a safety earth. Keep metal connection boxes and cable housings isolated from other metal parts. Metal housings for intercom cables and connectors should be mounted in such a way that they are isolated from other metal cable and connector housings and from any other metal construction parts. Keep cables parallel as much as possible. When two (two channel) units in a network are connected by more than one cable, make sure that these cables are parallel to each other over the whole distance between those units. When using multipair cable, parallelism is ensured in the best possible way. [. . . ] It develops a DC potential over the line impedance which will be sensed by each station and interpreted as a Call signal. 18 mA quiescent 35 mA signalling 80 mA at max. impedance gain presence filter frequency response V electret mic 200 ohms 40 dB - 70 dB (adjustable internally) +6 dB at 5 kHz 200 Hz - 13 kHz (-3 dB) +9 V DC HEADPHONES DRIVER AMP max. SPL DIMENSIONS AND WEIGHT width height depth weight 3 mA rms > 150 Kohms 0 - 30dB adjustable 100 dBA 90 mm 38 mm 124 mm 260 gramms 9. 0 GUARANTEE This unit is warranted by ASL Intercom to the original enduser purchaser against defects in workmanship and materials in it's manufacture for a period of one year from date of shipment to the end-user. Faults arising from misuse, unauthorised modifications or accidents are not covered by this warranty. [. . . ]