Publication Number 53719. Issue 3, April 2012
SERVICE MANUAL FOR THE 13754 TGX150 INTERNAL RLAN TYPE A/B SC ETM
Page 11
calculate the amount of paper left on the roll. A “paper low” indication
and the number of tickets left can be displayed to the operator.
b.
a paper out microswitch, which is fitted inside the printer mechanism,
detects when there is no paper running through the printer head.
3.4.4 Memory Module Receptacle
The memory module receptacle is a square, plastic enclosure into which the driver inserts his
memory module at the start of his journey. The receptacle is mounted onto the control board
in the lower cover. The control board contains the necessary data transfer and power
electronics. The data transfer is via an infra-red link and power for the module is via an
inductive loop. The sides and lower face of the receptacle are shaped so that the module can
only be inserted one way.
The module is held in position in the receptacle by a manually operated spring-loaded latch.
Once the module is latched in position within the receptacle, it can only be released by
pressing the release button situated to the right of the slot (or if solenoid operated by pressing
a designated key on the keyboard. The internal spring then ejects the module a centimetre or
so out of the receptacle slot to allow full withdrawal manually.
3.4.5 ITSO Card Reader
The ITSO Card Reader is secured to the outer face of the top cover with its antenna PCB
secured to a mounting plate beneath the moulding on the upper side of the top cover. The
ITSO antenna board circuitry senses the presence of an ITSO smart card and reads the data on
it. The data is then passed to the Type A/B-2 Coupler PCB via the interconnecting cable
assembly.
3.4.6 Internal Radio LAN PCB Mount Assembly
The Internal RLAN PCB mount assembly contains the 802.11b Radio Module and PIC
Controller PCB that are fitted to a mounting plate on the underside of the top cover. The
Radio Module board plugs into the PIC Controller PCB. A ribbon cable connects the PIC
Controller PCB to the Memory Expansion & Internal Serial PCB in the lower cover. The
frequency band of RF transmission is 2.4 Ghz.
3.4.7 Printed Circuit Boards
Including the keyboard, there are eight printed circuit boards within the ETM. Four, the
control board, electronic serial number board, Memory Expansion & Internal Serial PCB and
the Type A/B-2 Coupler PCB are mounted in the lower cover. The keyboard / Display PCB,
is a component part of the keyboard and is mounted at the back of the keyboard itself. The
RLAN PIC Controller, Radio Module, antenna board and repeater display PCB are mounted
in the top cover.
The boards are described below.
