User manual ASL INTERCOM PS 130

[. . . ] The unit is equiped with a limiter for the gooseneck microphone, allowing the user to speak close into the microphone without giving rise to overload and distortion. Private conversation may be carried out via the headset connector with a headset or telephone handset. When a headset is connected, both the gooseneck microphone and speaker are disabled automatically. 2. 0 UNPACKING 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. If any damage has occured, please notify your dealer immediately so that a written claim can be initiated. [. . . ] GOOSENECK MICROPHONE A high quality electret noise canceling microphone. A limiter prevents the microphone preamplifier from clipping when speaking close into the microphone. HEADSET connector An XLR-4 type connector for the connection of a local headset when private conversation is desired. This headset must have a can impedance of 200 ohms (or greater), or each 400 ohms minimum when in parallel. phones When connecting a headset, the speaker and gooseneck microphone will be disabled automatically. 10 LOUDSPEAKER A high quality loudspeaker driven by a 1. 3 Watt amplifier. Speaker and gooseneck microphone automatically shut off when a headset is used. 2 3 CALL button This push button activates the call system. A momentary push will send a call signal to all stations connected to the intercom channel and the call LEDS will start flashing. Press and hold the button for 2 seconds will activate the call buzzer, if not muted. After the CALL button is released the LEDS will continue to flash for further 2 seconds. SIDETONE LEVEL trimmer This trimmer controls the level of your own voice as you hear it in the speaker or in the headset. SIDETONE HI trimmer This trimmer controls the rejection in the high frequency range. It compensates the capacity of the interconnecting cables and prevents the speaker from feeding back into the microphone (unit feedback). Adjustment procedure for both sidetone trimmers : - set trimmer in start position : fully clockwise. Adjusting the sidetone does not affect the level of your voice as it is heard by other stations. 8 9 4 5 4 User Manual PS 130 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland. 4. 0 FRONT PANEL CONTROLS AND CONNECTOR 5. 0 SIDE PANEL CONNECTORS 11 LINE connectors These XLR-3 connectors are for connecting the PS 130 to the intercom system. The male connector is for extending the intercom line to other stations. 6. 0 INTERNAL CONTROLS Inside the unit there are two trimmers to adjust the mic gain of the gooseneck microphone and the headset microphone separately. They can be reached as follows : - remove the screws of the bottom plate. - take away the plastic isolation plate. The two trimmers are labeled : GOOSE for the gooseneck microphone HEADS for the headset microphone. User Manual PS 130 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland. 5 7. 0 CABLING For the PRO 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. [. . . ] 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 trunks isolated from other metal parts. [. . . ]