Attenuator, Comparator and Attenuator Control. The circuit analyzes whether the TX(transmit) or
the RX(receive) signal is louder, and then it processed the signals such that the louder signal is
given precedence.
The Voice Detector provides a DC input to the Attenuator Control corresponding to the TX signal.
The Comparator receives a TX and a RX signal, and supplies a DC input to the Attenuator Control
corresponding to the RX signal.
The Attenuator Control provides a control signal to the TX and the RX attenuator to switch the
appropriate signals on and off. The Attenuator Control also detects the level of the volume
control to automatically adjust for changing ambient conditions.
1. Transmission/Reception signal path:
Refer to SP-PHONE TX/RX in
SIGNAL ROUTE
().
2. Transmission/Reception switching
The comparison result between TX and RX outputs as a DC level
of pin 25 of IC401.TX level is high ...... pin 26 = pin 22 - 6mV RX
level is high ...... pin 25 = pin 21 - 150mVComparator output is
connected to the attenuator control inside of IC601.
3. Voice detector
The output of the mic amp (pin 10 of IC401) is supplied to pin 14 of
IC401 as a control signal for the voice detector.
4. Attenuator control
The attenuator control detects the setting of the volume control
through pin 23 of IC401 to automatically adjust for changing
ambient conditions.
12.6. Bell Detection Circuit and Bell Generation Circuit
Circuit Operation: ( )...Line 2
When the bell signal is received from the line, it passes through C101 (C201) and R102 (R202),
turning PC5 (PC6) ON. As a result, pin 1 (pin 80) of IC801 becomes Low level. In this way, a ringer
tone which corresponds to each line is generated from
pin 25 of IC801.
This tone passes through the following path: pin 25 of IC801
R432
C446
R441
C433
R438
R466
C467
pin 20 of IC401
pin 16 of IC401
C469
Speaker,
the generated signal causing the tone ringer to produce a ringing tone.
12.7. Hold Circuit
Function:
This circuit is designed to hold a line which is IN USE in the handset mode or speakerphone
mode. In this case, the LED indication will change from a steady glow to a flashing indication.
Circuit Operation: ( )...Line 2
46
Summary of Contents for KX-TS3282B
Page 4: ...Note for Service Replace all three batteries if flashes 4 LOCATION OF CONTROLS 4 ...
Page 5: ...5 ...
Page 6: ...5 Display 6 SETTINGS 6 1 Connections 6 1 1 Connecting the Handset and AC Adaptor 6 ...
Page 9: ...9 ...
Page 12: ...6 3 Dial Lock 12 ...
Page 13: ...6 4 How to Release the Establishment of Dial Lock 13 ...
Page 14: ...6 5 Call Restriction 14 ...
Page 15: ...15 ...
Page 16: ...7 OPERATIONS 7 1 Making Calls 16 ...
Page 17: ...17 ...
Page 18: ...7 2 Answering Calls 18 ...
Page 19: ...7 3 FLASH Button 19 ...
Page 21: ...7 4 2 Selecting characters to enter names 21 ...
Page 22: ...22 ...
Page 24: ...24 ...
Page 25: ...7 4 4 Dialing 25 ...
Page 26: ...26 ...
Page 28: ...28 ...
Page 31: ...31 ...
Page 32: ...32 ...
Page 33: ...33 ...
Page 34: ...9 2 Problems with the Handset 34 ...
Page 35: ...9 3 Unit Turns Off When Pulse Dialing 35 ...
Page 37: ...9 7 If the Electronic Volume of the Speakerphone Does Not Work 37 ...
Page 38: ...9 8 If the Electronic Volume of the Handset Does Not Work 9 9 Intercom Does Not Operate 38 ...
Page 39: ...39 ...
Page 40: ...9 10 No LCD Display 40 ...
Page 41: ...9 11 LED Is Not Turned On 9 12 No Caller ID Display 41 ...
Page 42: ...10 TEST MODE 10 1 Test Mode Flow Chart 42 ...
Page 50: ...12 8 3 Voice Communication Block 1 Voice Transmission 50 ...
Page 52: ...Signal Pass Refer to SIGNAL ROUTE 13 SIGNAL ROUTE 52 ...
Page 53: ...14 CPU DATA 14 1 IC801 53 ...
Page 54: ...15 CABINET AND ELECTRICAL PARTS LOCATION 54 ...
Page 55: ...55 ...
Page 75: ...M KXTS3282B 75 ...
Page 77: ...J901 24 23 2 1 CN105 J903 MIC KX TS3282B CIRCUIT BOARD Operation Flow Solder Side View ...