Panasonic DP-MB545 / DP-MB537 / DP-MB536 / DA-FAP109 / DA-FAP110 Service Manual ▷ View online
45
DP-MB545/537/536 series
6.3.4.2.
Block Diagram
46
DP-MB545/537/536 series
47
DP-MB545/537/536 series
6.4.
NCU Section
NCU: (Network Control Unit)
Requires for connecting computers to public communication networks and send a dial signal to call the other party.
Requires for connecting computers to public communication networks and send a dial signal to call the other party.
6.4.1.
General
The NCU circuit is composed of the SmartDAA (IC101) and it's peripheral circuit and an EXT.TEL. Line relay (RLY100), Bell detec-
tion circuit. The SmartDAA implement the line interface characteristic such as DC mask, Return loss by modem(IC203) control.
The following is a brief explanation of each circuit.
tion circuit. The SmartDAA implement the line interface characteristic such as DC mask, Return loss by modem(IC203) control.
The following is a brief explanation of each circuit.
6.4.2.
EXT. TEL. Line Relay (RLY100)
1. Circuit Operation
Normally, this relay switches to the external telephone side and switches to the open side while OFF-HOOK.
IC203 (7) High Level
IC203 (7) High Level
→ Q203 ON → RLY100 ON
6.4.3.
Bell Detection Circuit
1. Circuit Operation
The signal waveform for each point is indicated below. The signal (low level section) input to IC300 (E19).
TEL LINE
TEL LINE
→ PC101 (1,2-4) → IC300(E19)
6.4.4.
TAM Interface Circuit
This circuit is to switch between FAX receiving and the external TAM’s message recording automatically.
For details, please refer to TAM Interface Section (P.48).
For details, please refer to TAM Interface Section (P.48).
48
DP-MB545/537/536 series
6.5.
ITS (Integrated telephone System) and Monitor Section
6.5.1.
General
The general ITS operation is performed by IC201 which has a handset circuit.
The alarm tone, the key tone, and the beep are output from modem (IC203).
The alarm tone, the key tone, and the beep are output from modem (IC203).
6.5.1.1.
Telephone Monitor
1. Function
This is the function when you are not holding the handset and can hear the caller’s voice from the line.
2. Circuit Operation
(Signal Path)
Signals received from the telephone line are output through at the speaker via the following path.
Signals received from the telephone line are output through at the speaker via the following path.
3. Signal Path
Refer to Check Sheet for Signal Route of MONITER RX (P.201).
6.5.1.2.
Monitor Circuit
1. Function
This circuit monitors various tones, such as (1) DTMF tone, (2) Alarm/Beep/Key tone/Bell.
2. Signal Path
a. DTMF Monitor
(Speaker Operation)
Refer to Check Sheet for Signal Route of DTMF Monitor (Speaker) (P.201).
Refer to Check Sheet for Signal Route of DTMF Monitor (Speaker) (P.201).
b. ALARM/BEEP/KEY TONE/BELL
Refer to Check Sheet for Signal Route of MONITER RX (P.201).
6.5.1.3.
TAM Interface Section
1. Function
When TAM is connected to this unit, the unit receives documents for FAX calls or the external TAM records a voice message
automatically.
automatically.
2. Circuit Operation
The TAM INTERFACE circuit consists of Soc(IC300) to detect the other party CNG signal, and RLY100 to separate EXT.TAM.
a. CNG Signal Detection Circuit
The CNG signal from the other party’s FAX is detected in modem (IC203).
(Signal path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.201).
(Signal path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.201).
b. Remote Receiving
This is the parallel-connected DTMF signal for the TEL or EXT.TEL mode between T and R.
When the other party is a FAX, the unit switches to FAX receiving.
(Signal Path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.201).
When the other party is a FAX, the unit switches to FAX receiving.
(Signal Path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.201).
Click on the first or last page to see other DP-MB545 / DP-MB537 / DP-MB536 / DA-FAP109 / DA-FAP110 service manuals if exist.