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TOA CorporationKOBE, This booklet readily explains a working principle of the EXES-6000system from a standpoint of the entire system and so, does not to the details of the circuits, CPU's or IC's. It is compiled with anemphasis placed on the descriptions of audio and dial signal flows thatare a base of the system, and the timing of their relative switches,which are explained by using block diagrams of actual circuits. Thebooklet is so compiled that the basic items considered necessary,such as link, PAM, time division switching, etc. are first explained to entering into the explanations of the actual systems with the aim ofmaking readers knowledgeable on the system by degrees. TABLE OF I. BASIC ITEMS1. Hands-free System1-1. Basic Principle of the Hands-free System1-2. Voice Switch2. Concept of Speech 2-1. Manual 2-2. Crossbar S2-3. Space Division and Time Division Methods3. Principle of Time Division(Pulse Amplitude Modulation) Signal3-2. PAM Signal Generating Process3-3. Demodulation of PAM Signal3-4. Sampling Pulse4. Principle of Time Division Multiplex4-1. Time Division Multiplex4-2. Access to Time Division Mu4-3. Time Division ExchangeII. VOICE SIGNAL AND DIAL SIGNAL FLOWS1. Voice Signal Flow2. Dial Signal 3. Dial Signal Receiving System4. Line Memory and Signal III. VOICE SWITCH CIRCUIT1. Operation Principle of the Switch Circuit1-1. Hands-free to Hands-free Mode1-2. Handset to Hands-free Mode1-3. Handset to Handset Mode2. Performance Comparison between New and Old Voice 2-1. Voice Switch Features of Duplex Line Unit for the EXES-5000, the EXES-1000 and the EX-162-2. Voice Switch Features of Duplex Link Unit for the IV. PAGING SIGNAL FLOW1. Paging System and Signal 1-1. Paging by an External PA Amplifier (Zone 1-2. Station (Group) Paging1-3. Block Diagram of Paging Interface (PI) Unit1-4. Paging Signal Flow2. Connection for Station Paging (Group Paging)V. PRINCIPLE OF CONFERENCE FUNCTION1. Example when One Station is in Conference2. Example when Two Stations are in VI. TIE-LINE SYSTEM1. Dial Signal Flow2. Voice Signal VII. DATA TRANSMITTING AND RECEIVING SYSTEM1. Function Setup1-1. DIP Switch Setting for the Data Transmitting Unit1-2. DIP Switch Setting for the Data Receiving 2. Principle of Data Transmitting and Receiving SystemVIII. 1~92, 34, 56~96, 78, 910~1810, 1117, 1819~2420~2321, 2225~3325~3026, 2728-3031~3334, 3534, 3536~3936, 3737~3940~5041~4741~4546, 4748~5051~5455~59 1. Hands-free SystemBasic Principle of the shows a basic principle of the hands-freesystem that permits duplex conversation to bemade between the calling and called partieswithout using their hands to lift their stationFeedback produced between the microphone andthe speaker by the following reasons, however,makes it impossible for the system to be in actuala) Both the speaker and microphone are housedin a small case, causing them to be located inclose proximity to each other.b) Speaker audio output level is high.c) Microphone is very Fig.1 Hands-free System1-2. Voice To make the hands-free half-duplex possible by preventing occurrence of suchfeedback problem, Toa EXES-6000 system usesvoice switch in its exchange that is able to detectsignal strength information from both lines and toautomatically select the speech line of highersignal level, while disconnecting another speechline of the lower signal level. See Fig. 2.Fig.2 Principle of the I. BASIC 2. Concept of Speech Link2-1. Manual ExchangeFig.3 Manually Operated Exchange (8 lines/2 links)Fig. 3 shows the simplest telephone system.When an attendant connects between 2 with a strap, speech path can be set up betweenthem. The strap represents a link, and the numberof links can be increased as the strap increases innumber. You may presume that the attendantfunctions as switch in this 2-2. Crossbar SystemFig. 4 shows the crossbar method which space division method in the tion of speech path. The space division method ismentioned in the next section 2-3. This method,however, has both the advantage and the dis-advantage; the advantage is that all stations in asystem can participate in the conversation at thesame time, while the disadvantage is that anincrease in the number of stations will greater number of switches as is evidenced by anexample of the EXES-6000 system with 128stations where the required number of switches – 128 = 16,256 Fig.4 Crossbar System Exchange (8 lines/full links) 2-3. Space Division and Time Division Methodsa. Space Division MethodFig.5 Space Division Method (8 lines/2 links)The method employed in Toa system. Withthis method, the system can do with the small number of switches if it is the small system.But if the system consists of many stations, switches are required than with the time divisionmethod referred to in the next section. the EXES-6000 system (128 stations/16 links) wasdesigned with this method, it would require (2 x128) x (16 x 2) 8192 switches in total.b. Time Division MethodFig.6 Time Division Method (8 lines/2 links)The method adopted in the EXES-6000 All stations are connected by one of each oftransmitting and receiving bus lines, we call"highway", and the speech signals are mplexed on the bus lines by means of pulses ofdifferent timing. If we compare this method withthe space division method by taking the sameexample of the EXES-6000 system (128 16 links), the required number of switches is 128x 2 + 16 x 4 = 320 pieces (this is the required number and not in agreement with acalculation made from the above Figure. Fordetails refer to later explanations.), which is farsmaller than that required with the space division 3. Principle of Time Division3-1. PAM (Pulse Amplitude Modulation) SignalIn order to convert an analog signal such asspeech into a pulse stream, a circuit must sampleit at periodic intervals. The amplitude of the pulsessampled is proportional to the amplitude of theoriginal signal at the sampling instant. This pro-cess is called Pulse Amplitude Modulation orsimply PAM.3-2. PAM Signal Generating ProcessFig.7 Waveforms for PAM SignalAfter modulated by the sampling pulseshaving periodic intervals (Fig. 7-(b)), the analogsignal (Fig. 7-(a)) is converted into such PAMsignal as is shown in Fig. 7-(c). However, the realintervals are so short that the original analog signal in Fig. 7-(c) and the signal in Fig. 7-(a) are almost identical.Fig. 8 shows the PAM signal generating process.In its block diagram, the analog signal (Fig. applied to the input is chopped by the ON andOFF operation of the switch. The switching iscontrolled by the sampling pulses with their highlevel causing the switch on and their low level theswitch off. Through this process, the PAM (Fig. 7-(c)) is delivered to the output.Fig.8 PAM Signal Generating Process 3-3. Demodulation of PAM SignalBoth holding capacitor and lowpass filter arenecessary to demodulate the PAM signal.(1) PAM signal potential of Fig. 9-(1) at eachsampling instant is held with the holding(2) Sampling pulse elements contained in thewaveforms of Fig. 9-(2) are eliminated throughthe lowpass (3) Through processes (1) and (2), the PAM signalis demodulated into such a waveform as isshown in Fig. 9-(3) which is identical with theoriginal analog signal.3-4. Sampling PulseIf a band-limited signal is sampled by pulseshaving regular intervals of time and a equal to or higher than twice the highest Fig.9 Demodulation of PAM Signalcant frequency, then the sample contains all theinformation of the original signal. 4. Principle of Time Division Multiplex4-1. Time Division MultiplexThe time division multiplex is a method to dividevarious signals by time and to place such ti-me divided signals on a single common line calledFig. 10 Time Division Multiplex4-2. Access to Time Division MultiplexIn Fig. 11-(a) at the right hand side, consider justhow many lines are needed to transmit 4 signals A, B, C and D to the outputs 1, 2, 3 and 4,(1) The simplest way is to connect between themas indicated by dotted lines in Fig. 11-(b) at theside. This method, however, in-volves such problem as that the more signals are used, the more grows thenumber of lines. (2) Another connection example like one in 11-(c) can be considered when you wish todevelop the previous connection in order toreduce the number of lines. The idea of thisconnection is that switches 1 and 2 aresynchronized with each other, through whichsignals A to D are transmitted in this order toeach corresponding output. In this event, thesignals delivered to the outputs 1 through 4are the RAM signal described in section (3) In the example of Fig. 11-(c), one switch hasmany contact points, but an actual syanalog switch as shown in instead of each contact point so that anindividual pair of analog switches (x and y) issequenced in the following When the analog switches x and y synchro-nized with each other are on, the signal A isallowed to go through to the output 1, andlikewise when x and y are on, the signal B isdelivered to its corresponding output 2. Thiscontinues till the signal D is sent out to itsoutput 4, and is again repeated from theHere we show the timing of each switch used inthe system of Fig. Fig.12 Timing ChartIn the above timing chart, 4 different PAM signalsof Fig. 11-(d) are on a highway (H W line), the stateof which is called "being time division multi-plexed". In Fig. 11-(d), the signals are quadplexed.Also, the frequencies (time intervals) of pulses (i) through (iv) are all the same, which arethe sampling frequency described in section 4-3. Time Division Fig.13 Time Division Exchange Block Diagram (4 lines/2 links)Shown below is the timing of each when a conversation is being made betweenFig. 13. (Voice signal flow: Mic AFig.14 Timing DiagramSpeaker C,Mic CSpeaker A) Here we show the voice signal flow of Fig. 13where stations A and B are conversing with eachother. For timing of each switch, refer to Fig. 14.— Timing "1" —(1) Switches Tx and Ry close at the timing "1" and Rx(Marked in red in the Figs. 13 and 14)(2) The voice signal from the microphone ofstation A is transmitted to LINK No. 1 via TxHW-T line and Ty. The signal between Txand Ty is the PAM signal. Now that Rx is leftopen at this timing, the signal delivered toLINK No. 1 will not go beyond this LINK wthe signal is held with a holding capacitor inorder to be demodulated into the voice signal. See section 3-3 "Demodulationof PAM Signal".— Timing "2" —(3) Switches Tx and Ry close at this timing.(Marked in green in the Figs. 13 and 14)The signal from station A held at LINK No. 1 istransmitted to the speaker of station C via, HW-R and Ry. The signal between Rx is the PAM signal. The signal from themicrophone of station C is, in the samemanner as described in (1) and (2) above,delivered to LINK No. 1 and — Second Timing "1"(4) The signal from station C held at LINK No. 1 issent out to the speaker of station A in thesame manner as in (3) above.Since the timings "3" and "4" have norelations with LINK No. 1, they are omittedfrom this the timings of 1. Voice Signal Fig. 15 Voice Signal Flow II. VOICE SIGNAL AND DIAL SIGNAL FLOWS Assume that stations No. 200 and No. 202 are inthe conversation through link No. 1.a) In this event, voice signal flows from No. 200 to station No. 202 as The voice signal is transmitted to the LM after being frequency-modulated in stationNo. 200 ..... demodulated into the analog signal in the PLL circuit (analog switch-es Tx, Ty, Rx and Ry close at the sametiming) ..... passes through Tx ..... enters theDL unit through highway HW-T (in link No. 1,b) The timing chart below shows actual timings and PAM signal wave forms on HW-Tand HW-R in EXES-6000 systems when thecross-connection is made between Ty and Rxand between Ty and Rx) ..... because Rxopen, the voice signal does not pass highway HW-R and is held in the link by a holdingcapacitor ..... At the next timing Tx, Ty, Rx, and open, and Tx, Ty, Rx, Ry close ..... thevoice signal held in the link passes through Rx..... enters the LM unit through HW-R ..... through Ry, the only switch that remains closedamong ones connected to HW-R ..... sent out tostation No. 202 connected in base frequency bandafter being amplified in the LM unit ..... can beheard from the speaker of station No. 202simultaneous conversation is being made be-tween stations No. 200 and No. 202.Fig. 16 Timing Chart in Conversation Stations No.200 and — 11 — 2. Dial Signal FlowFig. 17 Dial Signal FlowStation dialing operations cause the pulse corresponding to each key depressed to begenerated in the dial pulse generator, whichis sent out to the LMunit of the exchange.The dial streams are demodulated into the pulses with a dial pulse detector in the LM unit,and then transmitted to the CP unit through thedial data bus line.amplitude-modulates the FM carrierplitude-modulated 3. Dial Signal Receiving SystemFig. 18 Dial Signal Receiving SystemLet's assume that 202 (station number) is at station No. 200. The dial pulse detector locatedin the LM unit and intended for station No. 200, asexplained just before, delivers the following dialpulses to the output.These pulse streams comprising "2", "10" andin the above Figure, and are"2" pulses enterinverted by a transistor. They then pass the dial data bus line, and go into Input Port (IP)No. 0 of the CP unit. The CP unit is sending from its Output Port (OP) the scan signals to each of the 16 LM units in a manner (LM1 through LM16, again LM1 throughLM16 ...... this is repeated), and reads dial data of8 stations contained in each LM unit in a of second simultaneously with the of the scan strobe signals. The serial pulse streams that went into IP No. 0are transmitted to both the OC unit and HC unitafter being converted into parallel codes. In theHC unit, the data from the CP unit is written intoboth the line memory and signal memory ing to the address specified by the OC Station numbers of the stations in and the status of each link are written in the memory, of which contents become the controlsignals for the analog switches of the LM Signal codes, PIT or non-PTT mode and thestatus of each link are written in the signalmemory, of which contents become the controlsignals for the analog switches of the SG Fig. 19 Voice and Dial Signal Flows 4. Line Memory and Signal MemoryLine memory is a 32 words by 8 bits memoryformed from 4 RAM's of 16 words by 4 bits. Inthis line memory, station numbers of thestations engaged in coversations are writteninto the addresses that correspond to the linkto be used in the order of a calling side (T) andcalled side (R). The data is accessed and cyclically word byword in synchronization withthe link change-over switches (Ty, Rx) in the DL unit and controls the corres-ponding time division switch in the LM according to the contents of the data.Signal memory is a 16 words by 4 bits RAM, inwhich signal codes or PTT/non-PTT mode eachlink uses are written. Signal switches (Syof the DL unit's links and time division switch-es (Sx) in the SG unit are controlled withthe data read out in the same manner as that ofthe line memory.Memory maps of the line memory and signalmemory are as Contents of the line memory when stations No.200 and No. 202 are engaged in a using link No. 1.Table of Service Signal Calling tonePrivacy toneBusy Dial toneZone paging ment toneAll-call paging prean-nouncement toneHolding Confirmation tone It is already mentioned voice switch is necessaryfor the hands-free conversation. Here, we the principle of the voice switch circuit used in theEXES-6000 system. The voice switch circuitmentioned here is an improved version of onethat is used in the EXES-5000 The voice switch is employed in the DL unit andits operations differ depending on the tion mode (hands-free or handset) between theFig. 20 Block Diagram of Voice Switchand Peripheral C III. VOICE SWITCH CI 1. Operation Principle of the Voice Switch Circuit1-1. Hands-free to Hands-free ModeGiven below are operation procedures of thevoice switch when stations A and B are talking toeach other in the hands-free mode and soundpressure level at a mic of station A is higher thanthat at station B. See Fig. 22(1) A signal flow from mic A:Similarly, a signal from mic B flows as (2) A comparator compares signal strength fromstations A and B.(3) Since a signal level from station A is higherthan that from station B, switch SW(A) closes andSW(B) opens, thus permitting transmission of thesignal from mic A (signal A) to speaker B.At the same time, ATT(B) is activated and thesignal from mic B attenuated by ATT(B) is trans-mitted to the comparator. In this event, ATT(A) isnot activated. The signal A, therefore, is sent tothe comparator without (4) Therefore, the signal A that is fed fromspeaker B back to its mic is sent to the compara-tor after being attenuated in ATT(B), allowing notonly signal A to be still kept higher at thecomparator but also the status of (3) above to be* The EXES-6000 system uses FET's for theswitches SW(A) and (B). This makes response at switching longer than that of theFig. 21 Voice Switch Transient ResponseFig. 22 Main Circuit Activated in Hands-Freeto Hands-Free Mode 1-2. Handset to Hands-free Fig. 23 Main Circuit Activated in Handset to or Handset to Handset Assume that in Fig. 23, station A in the handsetmode is connected to station B in the hands-free(1) A 40Hz handset mode signal and voice signalfrom station A are transmitted to the DL unitvia the LM unit and HW-T.(2) Only the voice signal is sent out from B, which is similarly transmitted to the DL(3) The 40Hz handset mode signal from station Apreceeds to 40Hz SIGNAL DETECTOR (A),and its output level becomes high, while thevoice signal is sent to VOICE SWITCH (A)through a high-pass filter (HPF).(4) The voice signal from station B passesthrough HPF and proceeds to VOICE SWITCH(B). Since no 40Hz signal is sent out fromstation B, the output level of 40Hz DETECTOR (B) is kept low. The status of elements after this stage is shown in Fig. 24. Fig. 24 Status of Logic and Voice Signal Flowin Handset to Hands-Free ModeAt last, both VOICE SWITCHES (A) and (B) close,providing full duplex conversation. In this SIDE TONE CIRCUIT is not activated.The side tone circuit is a circuit that enables atalker using a station handset to hear his ownvoice through a handset ear speaker. In the caseof the conversation mode used in this section, avoice spoken into the mic of station A comes outof the speaker of station B. But now that station Bis in the hands-free mode, that voice from thespeaker is fed back to its mic, which in turn can bethrough the handset ear speaker of stationA, thus eliminating the necessity of activating theside tone circuit. See Fig. 25.Fig. 25 Side Tone on Handset to STATION ASTATION B 1-3. Handset to Handset ModeAssume that in Fig. 23, both stations A and B arein the handset mode and (1) A 40Hz handset mode signal and voice signalare transmitted from the both stations to theDL unit via the LM unit and (2) The 40Hz handset mode signal (A) proceedsto 40Hz SIGNAL DETECTOR (A) and another40Hz signal (B) to 40Hz SIGNAL (B), resulting in a high level output at the bothdetectors. Similarly, each of the both voicesignals is transmitted to VOICE and (B), respectively via HPF. The status oflogic elements after this stage are shown inFig. 26.Fig. 26 Status of Logic and Signal Flowin Handset to Handset ModeBoth VOICE SWITCHES (A) and (B) close, ing full duplex conversation. In this event, the sidetone circuit is activated, and the both stations (A)and (B) enable its talker to hear his own voicefrom its handset ear 2. Performance Comparison between New (Used in the EXES-6000)and Old (used in the EXES-5000) Voice Switches2-1. Voice Switch Features of Duplex Link Unit (DLU-52, DLU-11A, etc.) for the EXES-5000, the EXES-1000 and the EX-16Fig. 27 Old Voice Switch CircuitQuick voice switch response permits easyinterruption in conversation, resulting in performance in low noise while in high noise condition, the action is unstable.Usable under up to 60-phon Subject to pulsive noise (typewriter, etc.), andunstable operation in Acoustic feedback by echo or reverbration maycause the circuit to malfunction.2-2. Voice Switch Features of Duplex Link Unit (DL-62/62A) for the EXES-6000Improved voice signal detection circuit high performance against pulsive malfunction due to acoustic feedback.Sensitivity of the voice signal detection is controlled automatically according to thedifference of the noise levels between So, conversation is possible under the noiselevels as high as 70 to 75 Transient response of the voice switch im-allows comfortable interruption in con- 1. Paging System and Signal FlowIn the case of normal conversation, the speech path system is formed by stations, LM unit andDL unit as shown in Fig. 28.Fig. 28 Voice Signal Flow between StationsTo have the paging function in the system, use a PA amplifier and external speakerinstead of station B in Fig. 28. The PI unit isrequired as interface for this purpose. Refer to 29.When paging, just make a call from the 1-1. Paging by an External PA Amplifer (Zone Fig. 29 Voice Signal Flow on External Speaker Paging IV. PAGING SIGNAL FLOW 1-2. Station (Group) Besides the paging by an external PA amplifier, itis possible to page using the station speakers. Inthis event, only one-way speech path is formedfrom the paging station mic to the paged stationspeakers. See Fig. 30.Fig. 30 Voice Signal Flow ofStation Paging andZone 1-3. Block Diagram of Paging Interface (PI) UnitFig. 31 Block Diagram of PI Unit (PI-62) Fig. 31 shows block diagram of the PI unit. One PIunit is provided with 3 paging-zone outputs inPI-60 and 8 paging-zone outputs (all call + 7zones) in PI-62. Designed so that a maximum of 1(for EX-600) or 2 (for EX-610/620) or 4 (for PI units can be mounted, the EXES-6000 canhave all call plus up to 3 paging zones (for or all call plus up to 15 paging zones EX-610/EX-620) or all call plus up to 31 pagingzones (for In Fig. 31, the paging signal (PAM signal) fromHW-R passes through analog switches andappears at each zone output (P0, P1-P7). Thesignal that has reached to P0 also pro-ceeds to each zone output (P1-P7) throughjumper wire (JW) and becomes an all call.An incoming signal takes 2 separatecourses at each zone output of the PI unit, andone goes to each output section in the LM unit viaan assignment part of PI-60 (for EX-600) or anassignment plug (for EX-610/EX-620) or assignment unit (SA) (for utilized forusers to assign zones for station paging, another to a PA amplifier for external paging viaan output transformer. In addition to this, relaymake contacts are provided as output for the PAamplifier to allow remote ON-OFF operation ofthe PA amplifier.The output P0 is seldom used practically becauseit is used for all call purpose. When using 2 ormore PI units, by cutting a jumper wire (JW) onthe second unit or its subsequent units, theoutput P0 of the unit can be used as one of zone Fig. 32 shows a single LM unit in which zones aredivided into 2 by cutting JP6:Zone 1 (P1): Stations No. 200 — No. 203Zone 2 (P2): Stations No. 204 — No. 207(A) Here, supposing paging is made from No. 202 over zone 2 by using Link No. 1 Fig.(1) the voice from mic of station No. 202 passesthrough Tx ... HW-T ... Ty and is transmittedto Link No. 1, where it is (2) Rx and Py close at the next timing, and thevoice that has been held branches into 2outputs after passing through Rx ... HW-R ...: one goes to an external PA amplifier forzone 2 via transformer, and the other is sentback to the LM unit and transmitted to thespeaker of each station (No. 204 throughafter passing through JP7 JP9, R522, R622, R722 and R822.(B) When all-call paging is made from station No.204 by using Link No. 1 (Fig. (1) The voice from mic of station No. 204 through Tx ...HW-T ... Ty, and is transmittedto link No. 1, where it is (2) Rx and Py close at the next timing, and thevoice that has been held passes through Rx HW-R ... Py(3) The signal sent to P is routed to all zones(No. 1 through No. 15) via jumper wire Then the signal to each zone is divided into 2signals, and one goes to an external PAamplifier for each zone through trand the other is sent back to the LM unit, andthen to the speaker of stations No. 200 to No.203 through JP3 to JP5 and to the speakers ofstations No. 204 to No. 207 through JP7 toHere, station No. 204 is a paging station. Lestthe voice from this station should come intoits speaker, it is so designed that the voice isattenuated in the LM unit. This also applies tothe stations in conversation. When any sta-tion in the same paging group does not to be paged, this can be accomplished bycutting the resistor (R122/R222.../R822) in theLM unit for that station.1-4. Paging Signal Flow Fig. 32 Zone Paging Signal Flow Fig. 33 All-Call Paging Signal Flow Fig. 34 Station Paging Zone Assignment (EX-630) 2. Connection for Station Paging (Group Paging) Assigning each station to the designated zone will require the assignment plug for theEX-610 and EX-620, and the SA unit (SA-64) forthe EX-630. Supose that 4 LM units, LM(1) toLM(4) (32 stations, through No.231) areused in a system, with stations No. 200 to No.203 assigned to zone P1, stations No. 204 to No.220 to zone P2 and stations No. 223 to No. 227 tozone P3. See Fig. 34. The station number for eachgroup should be consecutive (1) To separate each zone, cut jumper wire JP6of LM(1), JP7 and JP9 of LM(3) and JP6 ofLM(4). When the paging group has a stationwhich does not require to be paged, the resistor in the LM unit for that station. Inthis example, the resistor in LM(3) for stationNo. 217 is cut.(2) Make connections for paging zone assign-ment in the SA unit.(2)-1 The exchange is so designed that the pagingoutputs of the PI unit are connected to theinputs PAGING No. 1 to No. 31 of the SAunit, and the paging inputs of the LM unit tothe outputs LM No. 1 to No. 32 of the SATherefore, each input of the SA unitneeds to be connected to the first or laststation number of the LM unit. In thisexample, the input PAGING No. 1 is con-nected to station No. 200, PAGING No. 2 tostation No. 207 and PAGING No. 3 to 223.(2)-2 When a certain paging zone extends to morethan one (1) LM unit, connect between thelast and first inputs of the LM units iIn this example, STATION No. 207, No. 208,No. 215 and No. 216 are connected for zoneP2 because it extends to 3 LM units. Anotherconnection is made between STATION No.223 and No. 224 for zone P3 because itextends to 2 LM (2)-3 Because each paging input of the LM units isgrounded through jumper wire in the SA unitto prevent cross-talk, cut the jumper wires (inthe SA unit) corresponding to the LM used for paging. In this example, the follow-ing jumper wires in the SA unit are No. 200 and No. 207 for LM No. 1No. 208 and No. 215 for LM No. 2No. 216 and No. 223 for LM No. 3No. 224 for LM No. 4As far as LM unit (4) is concerned, when thepaging group is assigned as shown in its corresponding jumper wire No. 231 in theSA unit should not be cut.(3) When using 2 or more PI units, cut the paging jumper wire in the second and itssubsequent PI units. Fig. 35 shows an example where 4 stations (A) to(D) are engaged in conference using the ence function (CL unit is Fig. 35 Block Diagram of CL Unit1. Example when One Station is in ConferenceSupposing station (A) alone is speaking, the signal flows as Timing 1. Station (A)'s mic ... HW-T ... HPF ...Voice switch (A) ... (Voice is held)Timing 2. Mixing point (B) ... HW-R ... S(B)'s Timing 3. Mixing point (C) ... HW-R ... (C)'s Timing 4. Mixing point (D) ... HW-R ... (D)'s V. PRINCIPLE OF CONFERENCE FUNCTION In this instance, the voice switch (A) is ON. Wewill explain why it is so.Fig. 36 Control Section of Voice Switch (A)In Fig. 36, the voice signal that passed throughHPF takes two courses: one goes to the voiceswitch and the other to the comparator (A). Thecomparator (A) compares the signal strengthbetween the signal from station (A) and one the mixing point (A), and provides "H" to "J"input of Flip-flop (A) if the signal level from (A) is higher. In this event, no signal appears atthe mixing point (A) because no other stationsthan station (A) are speaking. That is, the "J"input of Flip-flop (A) is "H" and so is the "Q"output, thus causing the voice switch (A) to beON. In this event, since the "Q" output isconnected to the "K" inputs of other Flip-flops (B)to (D), these "K" inputs all become "H" and the"Q" outputs of Flip-flops (B) to (D) are made "L".As a result, voice switch (A) alone turns on andother voice switches (B) to (D) are off.Consider another example where both stations(A) and (D) are speaking. (See Fig. 37).2. Example when Two Station are in Fig. 37 Control Section of Voice Switch (D)The voice signal from station (D) which passedthrough HPF is transmitted to both voice switch(D) and comparator (D). At the same time, thevoice signal from station (A) that appears at themixing point (D) is sent to the comparator (D). Thecomparator (D) compares the signal strengthbetween these signals from both stations. If thesignal level from station (D) is higher, the voiceswitch (D) turns on and the signal flows station (D) to stations (A), (B) and (C).To sum up, when the conference function (CLunit) is used, only one of the four voice switchesis activated just as in the case of hands-free tohands-free conversation mode. The are that the CL unit has no side tone circuit andthat the number of links corresponding to the DLunit is two. A maximum number of stations that can be usedin the EXES-6000 System in 32 for the EX-600, 64for the EX-610, 128 for the EX-620 and 256 for theEX-630. But it is possible to increase the totalnumber of stations by connecting two or threeexchanges (tie-line connection), except which has no tie line function. The explanation isgiven to the operation of the Tie-line interface (Tlunit) and flows of both voice and dial signals in thetie-lined system.In Fig. 38, suppose conversation begins station No. 200 connected to exchange A places acall to station No. 470 connected to exchange B.1. Dial Signal Trace green line in Fig. 38.Dial pulse stream generated in station No. 200 issent to the LM. It is detected by the dial pulsedetector in the LM, and transmitted to the CP.Station key Pulse The CP generates a pulse stream correspondingto the dial pulse stream and outputs it through OP(Output Port) of the OC (Output Control Unit) tothe TI.When the keyis dialed, the pulse stream isgenerated from the CP as shown to the right.The pulse stream from the CP in turn analog switches in the Tl to turn on and off at10ms intervals (100Hz) for the number of theThe signal of 2.6kHz is oscillated in the datatransmitting section of the Tl, which turns tone burst signal through on/off operations of theanalog switches.The Figure shown below is the process to the tone burst signal when a station dials the VI. TIE-LINE SYSTEM The tone burst signal sent to the dial receivingsection of the Tl in exchange B via a tie-line link isthen transmitted to the CP through the BPF(Band-pass Filter), amplifier and rectifier (Amp. &Rect. in the Figure), after converted into theoriginal dial pulse stream by the dial pulseconverter. The CP processes the dial pulsestream, and orders the HC to turn on or off thetime division switch for the speech path.In Fig. 38, a red line shown the voice signal flowfrom station No. 200 to station No. 470, and agreen dotted line represents a dial flow from station No. 470 to station No. 200.2. Voice Signal FlowSee red lines in Fig. 38.Assume that conversation flows from station No.200 to station No. In exchange A,(1) the voice signal flow when both Tx and TyStation No. 200 ... Tx ... HW-T ... Ty ... link No. 1(voice is held)(2) the voice signal flow when both Rx and LyLink No. 1 ... Rx ... HW-R ... Ly ...TlThe PAM signal is demodulated into the voice signal in the Tl unit, which passes throughtie-line link No. 1 and flows to the data receiving(audio signal transmitting) section of the Tl inexchange A. It is then transmitted to the datatransmitting (audio signal receiving) section of theTl in exchange B.In exchange B,(1) the voice signal flow when both Lx and Ty ... HW-T ... Ty ... link No. 1 (voice is held)(2) the voice signal flow when both Rx and RyLink No. 1 ... Rx... HW-R ... By ... Station No.470A red dotted line in Fig. 38 represents the voicesignal flow from station No. 470 to station No. The signal that flows in the tie-line link is notthe PAM signal but the analog voice signal (baseband). The on/off timing of time division switch forforming the speech path in exchange A is com-pletely independent of that in exchange B.A single Tl unit has 8 each of data transmitting andreceiving sections, meaning 8 tie-line links. Whenone (1) Tl unit is mounted on each exchange,there are 8 speech links between exchanges A (No.200~327) (No.470~597) By using the Data Transmitting Unit DT-E11G or DT-E11) and Data Receiving Unit(DR-B61) in the EXES-6000 System, the ON/OFF operation of various indicators and thecontrols of other equipment are possible fromany master station. This is an optional Fig. 39 shows the applications.Refer to Installation Manual of each CPunit for functions of these In/Out annunciation Personal in and out registrationthat is indicated by a lamp canbe accomplished by using per-sonal numbers. (Up to 500Destination indicator panelWhen a person registers hispersonal number at the station,the station number at whichthe registration was made canbe indicated by the lamp. (Amaximum of 32 and persons can be indicated.)Calling party indicator panelThe indicator panel is to be setup at the called station station numbers are indicatednumerically in the panel includ-ing one which makes a while the called station is busyor in privacy (a maximum of 8waiting stations can be The panel can also indicate thenumber of waiting stations.(Up to 32 specified stations canhave the panel)Calling party indicator panel(lamp type)When the called station havingthe indicator panel receives acall, the calling station is indicated by the lamp untilthe conversation is over orwhen the called station is busyor in privacy. (A maximum of 8stations or groups can have theIt is possible to call a holder from any master station.The called person can respondto the call from the nearestmaster station (The pager sys-tem should provide bility to interface with Toa receiving unit.)Prescription display board(lamp type)The prescription number readyfor delivery is indicated by thePrescription display Prescription numbers ready fordelivery are numerically Room condition indicatorWhether a room is occupied ornot is indicated by the CCTV camera remoteCCTV cameras can be ated remotely.VTR remoteVTRs can be operated re-Door remote(3) Connect between the Data Transmitting Unit DT-E60 and the Data Receiving UnitFig. 39 Applications of Data Transmitting and Receiving VII. DATA TRANSMITTING AND RECEIVING (1) Each indicator panel needs to be made by using the Data Receiving Unit DR-B61.(2) An interface with the DR-B61 built inside is necessary for each remote operation.DR-B61 with 2 non-polar wires. The data transmitting unit (DT) converts thedata received from the CP unit in the ex-change, and transmits the converted data tothe data receiving unit (DR). After receiving thedata, the DR will control 32 relays contained init. The DR-B61 is a printed circuit assembly, and users need to provide desiredindicators or controllers by using it.1. Function Setup (DIP switch setting)1-1. DIP Switch Setting for the Data Transmitting Unit DT-E60, ET-E11G orA maximum of 16 data transmitting units canbe connected in parallel per exchange. It ispossible to determine the channel number ofthe unit by setting the DIP switch on the PCboard inside the unit. See Fig. 40.The function that corresponds with the channelnumber varies according to the CP unit to beused. So, refer to Tables 1 through 4 whenselecting the desired function with the DIPFig. 40 Data Transmitting UnitNote. The number of channels available fromeach type of CP unit:CP-60 CP-62 CP-63 CP-64 0 ~ CH. 1In any case, a maximum number of the DTunits that can be used is 16, and the number of each DT unit is freely selectable. (Itis possible to use all the 16 DT units forChannel No. 1.) Table 1. CHANNELS VS FUNCTIONS FOR CHANNEL SELECTIONCH. 1WORD NO.One-shot Make(100 contacts)8 Selectable Make(9 units)In/Out (100 persons)Pager Control(100 pagers)Calling (32 stations)Calling and calledparty indication(32 stations)One-shot make output is delivered for1 to 2 seconds when a function code isOne contact out of 8 selectable makeoutputs is obtained for about 1 or 2Personal in and out registration canbe accomplished at any station by using personal max. 100 IN/OUT annunciations maybe done.Make output (100 contacts) isavailable for pager control.Up to 32 stations calling one (1) samestation (or 1 group having stations ofconsecutive numbers) can beindicated with lamp.A maximum of 32 stations in theconversation mode including stations can be indicated with lamp.APPLICATION ITV camera VTR control VTR control Use of In/Out annunciationpanel with personel withpersonal number function. Pager A maximum of 8 groups ofcalled stations can have apanel which is within each group. Can be divided into up to 8 Table 2. CHANNELS VS FUNCTIONS FOR CHANNEL SELECTIONCH. 2CH. 4CH. 5CH. 6CH. 10CH. 11IN/OUT (500 Make/Break (512/100 One-shot Make Output(500/50 (1) 4 Decimal digits (9 units)(2) Decimal Output(9 units)(3) 8 Selectable Make Output.(9 units)(4) Pager (100 pagers)(5) 8 Selectable One-shotMake Output (9 Decimal Output(99 units)8 selectable make Output(64 units)Calling Party IndicationNumerical-type (1)Calling Party IndicationNumerical-type (2)Calling Party Indication(One Station; One Lamp)Calling Party Indication(One Station; One Lamp)Indication (1)Indication (2)Personal in and out registration canbe accomplished at any station by using personal numbersMax. 500 IN/OUT may be done.Make/Break contacts can be availableat any Master contacts can beavailable at any Master Indicate by 7 segments LEDs.10 Selectable Decimal Outputs areavailable with 7 segments LEDs.One contact out of 8 selectable makeoutputs is obtained. "Clear" ration makes all 8 relays break.Make output (100 contacts) isavailable for pager coOne contact out of 8 selectable makeoutputs is obtained for about 1or 2 seconds.10 Selectable Decimal Outputs areavailable with 7 segments One contact out of 8 selectable makeration makes all 8 relays When a station with a Display is called, calling party number isover and also when the called stationis busy or in privary.Max. 128 Calling station numbers canbe indicated when designated station with Display Board is The numbers of called stations havingan indication panel can be program-med at No. 200 station.When a person makes his ownPersonal Programming at thethe registration was made can beindicated by the lamp.APPLICATION IN/OUT Door IN/OUT Annunciation ITV camera select VTR control Prescription annunciation Room condition Destination indication Pager VTR control Room condition indication Destination Room condition indication Destination The number of called are No.201 ~ The number of called stationsare No.217~No.232. The group number of station(s). No. 1~4 The group number of station (s). Personal number No. 1000~ 1015 Personal number No. Table 3. CHANNELS VS FUNCTIONS FOR CP-63CHANNEL SELECTIONCH. 1CH. 2CH. 3*1. Each exchange has an independent control system, and it isimpossible to control the Data Transmitting Unit of the otherexchange from the station connected to the different *2. Can only be connected to the exchange A (Station No. 200 ~327). It is impossible to call the pagers from any station notconnected to the exchange A. However, the response to a call is possible from any station regardless of the exchange it isconnected to.IN/OUT AnnunciationPersonel in and out registration canbe accomplished at any Master sta-tion by using personal numbers. Max.500 IN/OUT annunciations may bedone. (All the 3 exchanges the same indication)IN/OUT Annunciation(1) One-shot Make Output(50 contacts)(2) Make/Break (100 contacts)(3) 8 Selectable Make O(9 unit One contact out of 8 selectable makeoutputs is obtained. "Clear" tion makes all 8 relays break. *1Make/Break contacts can be availableat any Master station. *1One-shot make contacts can be avail-able at any Master station. *1ITV camera selectionVTR controlDoor RemoteIN/OUT Destination indicationVTR control(5) 4 Decimal digits output(9 unit blocks)(4) Decimal Output(9 unit blocks)10 Selectable Decimal Outputs areavailable with 7 segments LEDs. *1Room condition indication.Prescription annunciationThe group number of calledstation(s). No. 1 ~ 4The group number of calledstation(s). No. 5 ~ 8Indicate by 7 segments LEDs. *1Make output (64 contacts) are able for pager control. *2(6) Pager Control Output(64 contacts)Calling Party Indication (1)(One Station; One Calling Party Indication (2)(One Station; One Max. 120-Calling station numbers canbe indicated when designated station with Display Board is The numbers of called stations an indication panel can be program-med at No. 200 station. (Only thecalling stations within the sameexchange can be indicated by a lamp) Table 4. CHANNELS VS FUNCTIONS FOR CP-64CHANNEL SELECTIONCH. 1CH. 2CH. 3CH. 4CH. 5CH. 6CH. 7CH. 8CH. 9CH. 10CH. 11CH. 12CH. 13CH. 14CH. 15Make/Break (512/100 One-shot Make Output(1) 4 Decimal digits (9 units)(2) Decimal Output(9 units)(3) 8 Selectable Make Output.(9 units)(4) Pager (100 pagers)(5) 8 Selectable Make Output (9 unit)(99 units)8 selectable make (64 units)Calling Party Numerical-type (1)Calling Numerical-type (2)Calling Party Indication(One Station; One Lamp) (1)Calling Party Indication(One Station; One Lamp) (2)Calling Party Indication(One Station; One Lamp) (3)Calling Party Indication(One Station; One Lamp) (4)Indication (1)Indication (2)In/Out Annunciation (1)In/Out Annunciation (2)Make/Break contacts can be availableat any Master One-shot make contacts can beavailable at any Master station.Indicate by 7 segments LEDs.10 Selectable Decimal Outputs areavailable with 7 One contact out of 8 selectable makeoutputs is obtained. "Clear" ration makes all 8 relays Make output (100 contacts) isavailable for pager One contact out of 8 selectable makeoutputs is obtained for about 1or 2 seconds.10 Selectable Decimal Outputs areavailable with 7 segments LEDs.One contact out of 8 selectable outputs is obtained. "Clear" ope-ration makes all 8 relays break.When a station with a Display is called, calling party number isindicated until the conversation isover and also when the called stationis busy or in privary.Max. 256 Calling station numbers canbe indicated when designated station with Display Board is called.The numbers of called stations havingan indication panel can be med at No.200 When a person makes his ownPersonal Number Programming at thestation, the station number at the registration was made can beindicated by the lamp.Personal in and out registration canbe accomplished at any station by using personal Max. 1000 IN/OUT may be done.APPLICATION Door Remote IN/OUT Annunciation ITV camera select VTR control Prescription annunciation Room condition in Destination indication Pager VTR control Room condition indication Destination Room condition indication Destination The number of called stationsare No.201~No.216. The number of called stationsare No.217~No.232. The group number of station(s). No. 1~2 The group number of calledstation(s). No. 3~4 The group number of station(s). No. 5~6 The group number of station(s). No. 5~6 Personal number No. Personal Personal number No.1000~1503(504 persons) Personal (496 1-2. DIP Switch Setting for the Data Receiving Unit DR-B61The DR-B61 will control 32 relays after the data of 512 bits (16 bits × 32 words) from thedata transmitting unit. For example, word 1covers No. 0 through No. 15 and word 2 No. 16through No. 31 when the IN/OUT panel is used.One (1) word consists of 16 bits (16 relays), andeach DR unit has a 2-word There are 32 words (WD.0 — WD.31), and anyword setting is possible including a case where allthe 16 DR units have word 0. Since the outputdata (function) corresponding to each channelvaries according to the CP unit to be used, refer tothe EXPLANATION OF DATA RECEIVING OUTPUT DATA of Installation Handbook for CPunit when setting the word number of each DRunit with the DIP switches of the DR unit, it ispossible to connect up to 50 DR units to one (1)DT unit. This makes a 100-word capacity, but amaximum number of types of word selectable isstill 32. When a system uses 50 DR units, forexample, such word arrangement is possible:WD.0 — WD.29 × 1 eachWD.30 × 35 3530 words35 words35 wordstotaling 100 Fig. 41 System Block Diagram of Data Transmitting andReceiving Units in CP-64 System 2. Principle of Data Transmitting and Receiving The CPU inside the CP unit has such memory thatstores the data as is shown in Fig. 42. When thespecific function code is dialed at station, the1-word data is stored in a designated area. The1-word data consists of 16 bits, and the 1-bit datais expressed as 0 or 1 in binary code, with 0 setfor relay OFF and 1 for relay ON. The simplestway of controlling the indicator or controller by thecontent of the data is to directly connect betweeneach 1-bit data and the device via a cable. Thetotal number of transmission wires in this case isequal to the number of bit data plus 1 line). A system using the CP-64 The data transmitting and receiving system em-ployed in the EXES-6000 mentioned requires only 2 transmission wires instead ofabove tremendous number of Fig. 42 Memory Map in CPU(16 × 32) × 15 + 1 = 7,681 Suppose that the data in Figs. 43 and 44 (1) isstored at an address of WD.1 (Word 1) of Channel1 of the CPU memory inside the CP unit.Fig. 43 System Block Diagram of Data Transmissionand ReceptionThe 1-word data consisting of 16 bits is ted to the DT unit via the 8-bit data bus. Firstly, the8-bit data (0th bit ~ 7th bit) is and secondly, upper 8-bit data (8th bit ~ 15th Thirdly, the 5-bit data representing data (word number) inside the memory is In the DT unit, each time these data are ted, they are latched at the address instructed bythe CPU. The 8-bit address data from the CPUcontains channel number and (latch IC) inside the DT unit. After the DT unitreceives a complete set of data ( Fig. 44), thedata is parallel-to-serial converted and phase-encoded (P.E.). (Seeof Fig. 44.) The start andthe end data are added to the beginning and theend of the P.E. data, respectively so that the DRunit may know the start and the end of datareception. (Seeof Fig. 44.) The P.E. data (pulse)is transmitted to the DR unit after its high and lowlevels are converted into frequencies of and 18kHz, respectively (that is, after being FSKmodulated). See Fig. 44.The DR unit goes through the process reverse tothat of the DT unit, and as a result, it obtains thesame data as that of the CPU memory of the CPunit. The finally obtained data activates the relays'contacts of the DR unit, thus permitting controlsof the indicator or controller connected to the DRAbove explanation is just about the data sing for (1) word. All the 512-word data are always sent out to the DT unit on a word-by-wordbasis regardless of the existence of the data in thewords, and are processed in the aforementionedmanner. The data of each of the words 0 through31 is transmitted from the DT unit to the DR unitat time intervals of 0.32 seconds. Fig. 44 Contents of Data from CPU and Conversion Processinto Transmitting Signal This chapter deals with how to find in the the defective card in the system installed, according to symptoms of defect.Now that the field repair is limited to thereplacement of the card, it is not referred tohow to repair the defective card at the nent level.Each symptom is given on conditions thatpower supply and stations work normally andthat the following are properly Initial programming setupCP unit's DIP switch settingMounting of each card on its designatedlocation in a cabinet rackIn order to find whether or not the station isfaulty, it is recommended to replace theoriginal station with normal one to see if thesame symptom will result. "XX unit is that appears in the flow chart means the typeof card that is the most suspicious for thecause. If replacing the card still does notremedy the symptom, try to find the othersuspicious card by following the signal flowfrom the input through reference to the fore-sections of this booklet. This also appliesto the other symptoms not mentioned in thisSymptom 1. Cannot dial. The dial data transmitted from the stationfinally comes into the CP unit's input portthrough the dial data bus line of the LM unit.The data bus consists of 8 lines, which areconnected to the input ports No. 0 through No.7, respectively. Each bus line corresponds tothe station numbers that skip every 8 num-bers; for example, the input port No. 0 corres-ponds to the stations No. 200, No. 208, No.216 .... and the input port No. 1 to the No. 201, No. 209, No. 217 and so on. There-fore, when dialing is impossible from a certainstation, whether or not the CP unit is faulty canbe determined by dialing from stations ofwhich numbers increase or decrease by 8 from the faulty station number. VIII. TROUBLESHOOTING Symptom 2. Call tone does not sound.How to check for a. and b. above.It is possible to confirm the called station and the type of service signal tone by the lampstatus on HC (1) How to find the called station number ( 45)Example for Called station number: 249 = 200 + 32 + 16 + 1Note. The lamp status is indicated by the binary code.The lamp for station No. 200 does not light.(2) Service signal tones ( Fig. 45)TONE ANDSPEECH MODEDuring OFF duration on Continuous Zone pagingAll call Priority/Executive priorityRegistration/Call holding/Mic-offFig. 46 Called Station Number and Code Indications on HC Units Symptom 3. Call tone is normal, but voice is distorted.Test proceduresa. Prepare a couple of normal b. Make a call from one station to c. Confirm the occupied link number with theLINK BUSY lamps of the HC unit. See Fig. 46.d. Check the voice distortion by actually makinge. Terminate the conversation by depressing Cbutton on the calling f. Follow the procedures (b) to (e) for 16 times(the total number of links) by using the samestations. In this event, the LINK BUSY lampsmust light in numerical order.Fig. 46 Link Busy Indication on HC Symptom 4. Call tone is distorted.Test a. Prepare a pair of normal stations.b. Make a call from one station to another bymeans of continuous calling tone,c. Confirm the occupied link number with theLINK BUSY lamp of the HC unit. See Fig. 46.d. Check to see if this calling tone is distorted.e. Terminate the call by depressing C button onthe calling station,f. Follow the procedures (b) to (e) for 16 times(the total number of links) by using the samestations. In this event, the LINK BUSY lampsmust light in numerical order.Symptom 5. Conversation is normal, but paging voice is distorted.Symptom 6. Cannot make PA paging.Confirm the proper DIP switch setting by referring toInstallation Handbook CP-60, CP-63 or BASEBAND SIGNALINGTransmission of a signal at its original frequencies, i.e., a signal not changed by modulation.A transmission channel for data from one of several sources to one of several destinations. Only onetransmission via the bus is possible at the time.A continuous frequency capable of being modulated, or impressed with a second (information carrying)CL (Conference Link Operates under the control of the HC unit to connect or disconnect the links for conversation among up to4 parties and conversation between 2 parties. One CL unit is provided with 1 conference link and 2 speechCP (Central Processing Reads out the exchange procedures written into the memory (ROM) and collates the data from stationsfor processing in succession.CROSS-BAR A switch having a plurality of vertical paths, a plurality of horizontal paths, and elecoperated mechanical means for interconnecting any one of the vertical paths with any of the CROSS-BAR SYSTEMA type of line-switching system which uses cross-bar switches.DL (Duplex Link Operates under the control of the HC unit to connect or disconnect the individual links for between two stations, changing over from the hands-free conversation to the full duplex conversationmode, or vice DUPLEX CONVERSATION SYSTEMAt any two stations in a Private Branch Exchange (PBX) system and an Intercom System mutualoutgoing/incoming and private conversation are possible. DUPLEX Simultaneous two-way independent transmission in both directions. Also called full-duplex transmission.Any of various types of indications used for identification, such as a work mark, or a character that the occurrence of some condition, such as the end of a FREQUENCY SHIFT KEYING (FSK)A form of frequency modulation used especially in telegraph and facsimile transmission, in which themodulating wave shifts the output frequency between predetermined values corresponding to thefrequencies of correlated sources. Abbreviated FSK.HALF-DUPLEX TRANSMISSIONA transmission system in either direction but not both directions simultaneously.Also called semi-duplex HC (Highway Control Turns on and off the time division switches at the LM, DL and SG units according to instructions receivedfrom the CP unit. The link busy indicator lamps on the front panel display the number of the link in use.A common path for conveying multiplexed PAM signals in time-division switching system.A connection between two LM (Line Modem Unit)Comprises a modulator to transmit signals from the stations to the speech link, a demodulator to send outsignals from the speech link to the station, a dial receiver and a scanning circuit that scans the "Privacy ON/OFF" conditions and "Handset ON/OFF" conditions. Up to 8 stations can be connected toone LM unit.OC (Output Stores temporarily the output data from the CP unit and distributes them to each unit. PARALLEL DATAThe data transmitted or processed parallelly and simultaneously, or constituted of bits arranged in parallelat a time. To transfer 8-bit data parallelly, for instance, 8 lines are PARALLEL TO SERIAL CONVERSIONOpposite to serial to parallel conversion.See "SERIAL TO PARALLEL PHASE ENCODINGIn general, a method to record binary data on magnetic recording media. The bit "1" or "0" is recorded bythe inversion of magnetic flux having different phases, as shown below.For instance, the change of magnetic flux from negative to positive is recorded as "1", and the from positive to negative as "0". This method applies to data transmitting and receiving system inPI (Paging Provides paging functions of PA paging and station paging. It sends out both paging voice signals and Make signals for power remote control of the PA amPLL (Phase-Locked Loop) Comprises a phase comparator, an LPF (Low-Pass Filter) and a VCO (Voltage Controlled Oscillator). Thephase comparator compares the phase of signal with that of the output signal from VCO, thenautomatically controls the VCO so that both phases, or both frequencies, coincide.SA (Station Paging Distributes each of paging outputs to each LM SA plug is used in EX-610/620, and SA unit in EX-630. SCAN STROBE SIGNALA control signal by which the CPU reads the dial data on the dial data bus at an optimum timing when theCPU scans the data.SERIAL DATAThe data in which bits are transmitted one after another when the data is processed or transferred. Thebits constituting the data are arranged in serial at instants. So they can be transmitted on a signal line.SERIAL TO PARALLEL CONVERSIONIn general, a CPU processes parallel data, while a transmitting device or a simple terminal processes serial data. When the data from the transmitting device or terminal equipment is transfered tothe CPU, the serial data is necessary to be converted into the parallel data. This is called Serial-To-ParallelSG (Signal Generating and Distributing Unit)Composed of 8 kinds of signal generators (calling, privacy/disconnected, busy, dialing, zone paging, all priority/executive priority, registration confirmation/call holding/mic-off) and distributors. This unitdistributes under HC control the required service signal tones to the individual SIDE TONEThe sound of the talker's own voice heard from his station handset.SPACE-DIVISION SWITCHING A type of switching system in which a speech signal is transmitted by spatial branched out connectionSPEECH PATHIn the multiplexed carrier system or radio system, a line on which voice signal transmitting is Tl (Tie-line Interface Unit)When tie-line system is built for connecting 2 or 3 exchanges, this unit transmits and receives the signals and dial data among the TIME-DIVISION SWITCHING A type of electronic switching system in which input signals on lines and links are sampled cyclically, andeach active input is associated with the desired output for a specific phase of the period.VCO (Voltage A oscillator whose oscillating frequency is varied with applied A symbol sequence which stores or processes it as a unit, and has not less than one meaning.For DR unit (DR-B61); 1 word = 16 TOA CorporationKOBE, Printed in