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The TX72 was withdrawn from new supply in March 1988.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 321 FEATUREPHONE. - 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 failure.
If difficulties are encountered during the above procedure, turn off the battery for a
few seconds and repeat the procedure.
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 has 21 dedicated feature keys, each of which gives immediate access to a specific facility on the
The TX72 has its own number store for short-code dialling. Up to 40 telephone numbers, each of up to 21 digits, can be
Taken from British Telecommunications Engineering, Vol. 4, July 1985
Last revised: September 21, 2010