Ricoh FACSIMILE FAX77, Field Service Manual

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DTMF
Dual Tone Multi Frequency: A method of diall-
ing using tones instead of pulses.
EFC
Estimated Fillbit Control: A Ricoh-developed
compression method used with MH or MR or
MMR. It reduces the number of fill bits on a
line, making transmission time faster.
EOM
End Of Message: A protocol signal that in-
forms the receiver that there are more pages
to follow, using different parameters.
EOP
End Of Procedure: A protocol signal that in-
forms the receiver that this is the end of the
page of data.
FCU
Facsimile Control Unit: A PCB which controls
the entire machine.
FTT
Failure To Train: A protocol signal that in-
forms the transmitter that either set-up infor-
mation and/or modem training was not
acceptable.
LB
Line Buffer: An area of memory where lines
of video data are temporarily held before
being passed on to the next process. This
helps to ensure a smooth flow of data.
LCD
Liquid Crystal Display: A display on the opera-
tion panel used to inform machine status and
programming prompts to the user.
LED
Light Emitting Diode: A diode that emits light;
used as an indicator lamp.
LSI
Large Scale Integration: A process of making
complex microchips.
MCF
Message Confirmation: A protocol signal that
confirms reception of the page just sent.
MH
Modified Huffman: A compression method
used to reduce the number of bits needed to
represent the facsimile data. MH coding is a
one-dimensional run length digital scheme of
coding black and white runs.
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