90
KX-FT982LS-B / KX-FT984LS-B / KX-FT988LS-B
(Causes and Countermeasures)
Fig. a
(Overlapping the Echo of the DIS signal and DCS signal)
Fig. b
(Countermeasure by Changing the CED Frequency)
No. Countermeasure Side
Echo Communication Problem Example
Countermeasure
Service Code
1
Sending side
Some time is needed to compare the level
of the receiving and sending signals for the
echo canceler. The header of the training
signal lacks due to a switching delay to
close S1.
Add a dummy signal to the beginning of
the training signal.
Service code (521)
(International mode select)
This countermeasure becomes
the default value.
2
Receiving side
The echo canceler function stops according
to a CED signal frequency of 2100Hz (S1
and S2 are both ON), a DIS signal is
returned as an echo, and a DCS signal
from the sending side overlaps the DIS
echo. Then the receiving side FAX cannot
retrieve the DCS signal.
(Refer to Fig. a)
Change to a 1100Hz CED signal fre-
quency. (Refer to Fig. b)
Service code (520)
(CED frequency select)
Receiving side
Change the regular rime of 75 msec
between the CED signal and DIS signal
to 500 msec. This will give at least 250
msec to recover the echo canceler
operation. (Refer to Fig. c)
Service code (593)
(Time between CED and 300
bps)
Sending side
The sending side FAX sends a DCS
signal not after receiving the 1st DIS
signal but after receiving the 2nd DIS
signal. (Refer to Fig. d)
Service code (594)
(Overseas DIS detection
select)
3
Sending side
Communication failure occurs in a long dis-
tance communication on the telephone line
without an echo canceler.
or
There are some cases (e.g. Mobil comms.)
which cause the collision of TX / RX signals
due to the delay / echo and noise of the
network / terminal. (Refer to Fig. e)
Decrease the transmission level from -
9 dBm to -15 dBm and the echo level
will decrease.
Service code (596)
(Transmit level set)
4
Sending side
Receiving side
Decrease the receiving sensitivity from
-13 dBm to about -32 dBm so an echo
signal will not received.
Service code (598)
(Receiving sensitivity)
5
Sending side
Receiving side
Set additional Pause time (Service
mode: code No. 774) in between the
original and its repeated signals, to pre-
vent the collision of the signals at both
end.
Service code (774)
(T4 timer)
Summary of Contents for KX-FT982LS-B
Page 2: ...2 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 12: ...12 KX FT982LS B KX FT984LS B KX FT988LS B 6 Technical Descriptions 6 1 Connection Diagram ...
Page 14: ...14 KX FT982LS B KX FT984LS B KX FT988LS B 6 2 1 General Block Diagram ...
Page 22: ...22 KX FT982LS B KX FT984LS B KX FT988LS B 6 4 2 Block Diagram ...
Page 24: ...24 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 72: ...72 KX FT982LS B KX FT984LS B KX FT988LS B Countermeasure ...
Page 73: ...73 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 74: ...74 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 75: ...75 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 76: ...76 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 77: ...77 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 78: ...78 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 79: ...79 KX FT982LS B KX FT984LS B KX FT988LS B REFERENCE Test Mode P 55 ...
Page 83: ...83 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 109: ...109 KX FT982LS B KX FT984LS B KX FT988LS B NG Wave pattern Note Refer to NG Example P 114 ...
Page 111: ...111 KX FT982LS B KX FT984LS B KX FT988LS B I O and Pin No Diagram ...
Page 114: ...114 KX FT982LS B KX FT984LS B KX FT988LS B 12 5 6 2 NG Example ...
Page 116: ...116 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 121: ...121 KX FT982LS B KX FT984LS B KX FT988LS B 12 5 9 2 Troubleshooting Flow Chart ...
Page 128: ...128 KX FT982LS B KX FT984LS B KX FT988LS B 13 Service Fixture Tools ...
Page 134: ...134 KX FT982LS B KX FT984LS B KX FT988LS B 14 2 2 How to Remove the P C Boards and Power Cord ...
Page 138: ...138 KX FT982LS B KX FT984LS B KX FT988LS B 14 3 3 How to Remove the Separation Rubber Flap ...
Page 139: ...139 KX FT982LS B KX FT984LS B KX FT988LS B 14 4 Installation Position of the Lead Wires ...
Page 140: ...140 KX FT982LS B KX FT984LS B KX FT988LS B ...
Page 148: ...148 KX FT982LS B KX FT984LS B KX FT988LS B 15 2 3 4 Copying REFERENCE Sensor Section P 124 ...
Page 153: ...153 KX FT982LS B KX FT984LS B KX FT988LS B 16 1 4 Power Supply Board ...
Page 155: ...155 KX FT982LS B KX FT984LS B KX FT988LS B 16 3 Test Chart 16 3 1 ITU T No 1 Test Chart ...
Page 156: ...156 KX FT982LS B KX FT984LS B KX FT988LS B 16 3 2 ITU T No 2 Test Chart ...
Page 157: ...157 KX FT982LS B KX FT984LS B KX FT988LS B MEMO ...
Page 170: ...170 KX FT982LS B KX FT984LS B KX FT988LS B MEMO ...
Page 180: ...180 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 1 Operation Panel Section KX FT982 KX FT984 ...
Page 181: ...181 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 2 Operation Panel Section KX FT988 ...
Page 182: ...182 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 3 Upper Cabinet Section ...
Page 183: ...183 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 4 Lower Cabinet Section ...
Page 184: ...184 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 5 Gear Block Section ...
Page 185: ...185 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 6 Screws ...
Page 186: ...186 KX FT982LS B KX FT984LS B KX FT988LS B 20 1 7 Accessories and Packing Materials ...