(3) Factors in international communications
(4) Other factors
Though these factors do not cause major trouble in voice transmission,
they sometimes are a problem in data transmissions such as facsimile
transmission.
The following Table A-1 shows phenomenon that occur due to these dete-
riorating factors and countermeasures that can be taken to remedy these
phenomenon.
Table A-1 Phenomenon Caused by Deteriorating Factors and Countermeasures
Deteriorating
Factor
Transmission
An increase in transmission loss
loss
drops the signal level on the receiv-
ing facsimile. Transmission quality
drops by deterioration of S/N.
Attenuation
Waveform distortion increases and
distortion
image signals become more difficult
to receive.
• Echo
• Time taken for establishing line connection
• Lightning
Noise
Telephone
Fig. A-5 Deteriorating Factors
Phenomenon
Distortion
Exchange
Countermeasure
Improve the S/N ratio.
• Increase the transmission level on
the ATT switch of the SSSW.
• Slow down the transmission
speed.
Adjust the NL equalizer of the
SSSW.
When black drops out in the image:
Turn NL ON.
When the image is blurred:
Turn NL OFF.
1
2
3
4
5
Telephone
6
A
çi
A–7