Gestetner B003 Service Manual page 750

4. DETAILED SECTION DESCRIPTIONS
4.1 OVERVIEW
The basic fax unit consists of two PCBs: an FCU and an NCU.
The FCU controls all the fax communications and fax features, in cooperation with
the controller board. The NCU switches the analog line between the fax unit and
the external telephone.
Fax Options:
1. Extra G3 Interface option: This provides one more analog line interface. This
allows full dual access. Up to two extra G3 interface options can be installed.
The option G3 unit consists of two PCBs: G3 board and NCU.
2. ISDN unit: This allows the fax unit to communicate over an ISDN line.
3. Fax Function Upgrade Unit: JBIG compression becomes available. In addition,
this expands the system's SRAM capacity to hold programmed telephone
numbers, memory files, etc.
4. Memory Expansion: This expands the SAF memory and the page memory
(used for image rotation); without this expansion, the page memory is not big
enough for image rotation at 400 dpi, so transmission at 400 dpi is not possible.
SM
Fax Function
NCU
G3
G3
or
CCUIF
G4
NCU
4-1
Upgrade
FCU
Expansion
Memory
Controller
MB
B360V501.WMF
B003/B004/B00/B007
OVERVIEW