Ricoh FACSIMILE FAX77, Field Service Manual

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MMR
Modified Modified Read: A modified version
of MR coding (see below).
MPS
Multipage Signal: A protocol signal that in-
forms the receiving fax that more pages are
to follow using the same parameters.
MR
Modified Read: A compression method (see
MH above). MR coding is a two-dimensional
digital coding scheme which works by com-
paring a line of data with the line above it.
MTF
Modulation Transfer Function: MTF is neces-
sary for transmitting details such as fine
points, thin lines, and complex characters.
NCU
Network Control Unit: A PCB that interfaces
the fax machine with the telephone line. It is
sometimes called a coupler.
NSF
Non Standard Facilities: A protocol signal
that informs the calling station of the called
station’s capabilities. It is also called Ricoh
Group 3.
NSS
Non Standard Set-up: The set-up command
in Ricoh protocol.
OPU
Operation Panel Unit: This PCB contains the
operation panel components.
PABX
Public Access Broadcast Exchange: A
switchboard found at the customer’s location.
PD
Pulse Dialling: A dialling method that uses pul-
ses; also known as Rotary Dialling.
PIN
Procedural Interrupt Negative: A protocol sig-
nal used to inform the transmitter that the pre-
vious page was not received satisfactorily
due to paper running out, paper jam, or be-
cause the Stop key was pushed on the
receiving fax.
PIP
Procedural Interrupt Positive: A protocol sig-
nal that confirms reception of the previous
page, and indicates that the receiver operator
wants to make a voice request.
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