The TX72 is an MF Featurephone, designed for use only on Monarch systems, which makes use of the Monarch facilities and provides in addition, repertory dialling, repeat last number and direct 'link extension' facilities. Its prime feature is the ability to set-up numerous "Recall and code facilities by the depression of a single key and to display invoked facilities, at all times, on a liquid crystal display. The Featurephone is driven from a standard extension card in the Monarch. It connects to the Monarch using a standard socket and is line powered, with a back-up battery for the repertory dial store.

In addition to the standard 12 digit keypad buttons the TX72 has 23 buttons for use with the repertory dial store and a further 26 buttons associated with specialised Monarch facilities.

The TX72 was withdrawn from new supply in March 1988.

Made by Rathdown Industries

Approved for connection to Monarch systems. Approval number 5/1000/GF/1981/PR.

On Installation, or after failure of line power conditions, the TX72 must be programmed with its own and link extension numbers. The tone caller must also be set to one of four different tones.
This procedure, which is detailed in the Operating Instructions Handbook, is reproduced below.

ACTION                                                  LCD DISPLAY
-  connect to line and turn "battery
   connect" switch through 90 degrees
   using a small screwdriver through the
   aperture in the rear of the case.                    INPUT EXTN

-  Key own extn number (e.g. 321)                       321

-  Press # key                                          LINK  EXTN

-  Key  number  of  "Link"    extension                 345
   (345) or # if Link extension is not
   required.  Note that if a Link
   extension  num,

-  Key number of "Link" extension                       345
   (345)  or # if  Link  extension  is  not
   required.  Note that if a Link
   extension number is not entered
   within 20 seconds, the TX72 will
   default to no link extension.

ACTION                                                  LCD  display

-  After one second, display changes                    TONE NO 1
   (There are four ringing tones available)             TO 4

-  Enter as appropriate (e.g. 2),  Change                 2
   by pressing key 1, 2, 3 or 4.  Note
   that if no Tone Number is entered
   within 20 seconds, a default tone of 1
   will be set.

ACTION                                                  LCD DISPLAY

-  Press # Key.                                         CANCEL ALL

-  After two seconds, display changes                   321 FEATUREPHONE
   to 'idle' condition.          

-  If a RECONNECT LINE message appears during this
   sequence press the two position line polarity (reset)
   button at the rear of the TX72 and wait two seconds.
   The display will then show CANCEL ALL, followed by

-  To change own or Link extension number, or tone
   calling level, press 'program' key followed by 'clear
-  To change own or Link extension number, or tone
calling level, press `program key' followed by 'clear
entry' key and re-initialise as described above.
Note that the repertory dial store is battery backed
and does not need reprogramming after line power

If difficulties are encountered during the above procedure, turn off the battery for a few seconds and repeat the procedure.

This is restricted to functional testing and if a fault is detected, complete unit change out. Suspected facility set-up faults should be proved to the TX72 by substituting with a standard MF4 telephone and entering the appropriate facility codes. It is possible for the TX72 display to indicate a facility as invoked which the Monarch failed to set-up. Check by cancelling all facilities and re-invoking. Check also for confirmation tone from the Monarch, via the call progress monitor, on successful facility set-up.

Note: the Monarch extension line card LED glows at approximately half power when the TX72 is on-hook. This is due to the TX72 drawing 2mA line current in its quiescent state. The difference between the busy and free states of a port should be easily identified, The status of Monarch ports should however, be confirmed using the LPS command in MMI before cards are removed from the system.

Merlin TX72 Featurephone

The Merlin TX72 Featurephone is a new terminal from British Telecom Business Systems to complement the Monarch telephone system. The TX72, a low-profile terminal of compact, modern design, gives users single-key access to the many Monarch facilities. It has a 21-digit liquid-crystal display to provide information to the user, and includes some additional features of its own including on-hook dialling, a microphone mute control, link extension and repeat last number.

The Merlin TX72 has 21 dedicated feature keys, each of which gives immediate access to a specific facility on the
Monarch system at the touch of a button. This simplifies operation by the user and encourages maximum usage of the wide range of facilities offered by Monarch. The dedicated feature keys are organised into four groups by common feature:
diversion and callback; call hold and retrieve; wait on busy and call-handling facilities (conference, shuttle and recall). The
display shows which feature is in use at any time and provides prompts to assist operation.

The TX72 has its own number store for short-code dialling. Up to 40 telephone numbers, each of up to 21 digits, can be
stored, entered and changed by the user; again the display shows the stored number being called. This store is in addition to the centrally stored short-code feature of the Monarch.
The link extension feature provided by the TX72 is useful where two people are working closely together. It enables a
second extension identity to be programmed in by the user so that direct calls can be made by single-button operation.
Additionally, calls can be diverted to the linked number by operation of a single key.

Taken from British Telecommunications Engineering, Vol. 4, July 1985


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