SAMSUNG InstallationDCS-816 February, 19992-92.7 Selecting Options of the Basic KSU (Figure 2-5)There are some hardware options to select in the Basic KSU: Memory Backup Selection, MusicSource Selection and MPD/ PRS selection for the analogue trunk ports on the Base board.2.7.1 Memory Backup SelectionThe system is equipped with 256Kbyte of data memory and memory backup circuitry (a supercapacitor) to protect the data in case of any power failure. The memory backup circuitry has aslide switch to enable backup. Before shipment, the switch is set OFF to prevent the supercapacitor from discharging during shipment and storage, and it should be switched ON afterinstalling and programming the system. Otherwise, the customer data and the programmed datawill be lost in the event of a power failure. (See Figure 2-5.)2.7.2 Music Source SelectionThe Basic KSU is equipped with a melody chip to provide music to stations and trunk lines asMusic-on-Hold or Background Music. In addition, it has an interface for an external music source,(CD player, radio etc).As the system provides only a single music channel for Music-on-Hold or Background Music, referto Figure 2-5 to select the music source at the end of installation. A shunt-pin switch selects themusic source: the internal melody chip or an external music source.How to connect the external music source is explained in Part 7.2.7.3 MPD/ PRS Selection and Installation (216 Base KSU only)The Basic KSU has two (2) analogue trunk interface circuits and each trunk interface is equippedwith a socket to install an option chip for Metering-Pulse-Detection (MPD) or Polarity-Reverse-Signal (PRS) detection. Please see the Figure 2-5 to know where to install the option chips andbe assured that the chips are firmly inserted in the sockets. One chip per line. The DCS optionchips for MPD or PRS can be installed.Concerning MPD or PRS installation, there are no additional hardware options to select. However,to install PRS chips or 50Hz MPD chips some additional jobs may be required in some countries.The capacitors (C214 & C215 for TRK1, C224 & C225 for TRK2) should be replaced with wire-jumpers. Please contact your dealer for details.