TELEPRINTER No. 87A

2 GENERAL DESCRIPTION
The Cheetah is a fully electronic microprocessor controlled machine with integrated keyboard, printer, electronic message store and visual display unit. Some of the more advanced features of the machine include automatic calling, uninterrupted off-line message preparation, short code calling, automatic date/time group insertion and diagnostics.

2.1 Keyboard
The keyboard is a solid state unit which uses capacitor switches for key-sensing and encoding. It has a 4 row conventional commercial typewriter keyboard layout with additional control keys separately grouped in distinguishing colours.

2.2 Printing Characters
The Cheetah employs a 9 x 9 dot matrix needle printing bead which when used with standard multiply teleprinter paper can produce up to 3 under copies. Up to 69 characters or spaces can be provided on each line. The ink ribbon is encased in a long life cassette for easy changing.

3.1 Design
In keeping with the new range of teleprinters, the Cheetah is elegantly styled and quiet in operation. The machine is ideally suited for both office or industrial environments. The machine is designed for reliability. Diagnostic programs identify faults automatically, thus eliminating the need for routine preventive maintenance.

3.2 Message Preparation
Messages are entered into the message store from the keyboard and presented to the operator on the visual display screen. Use of the 'word wrap' facility allows the operator to type freely, disregarding the end of line. The Cheetah's memory control acts if the text exceeds 69 characters or spaces and automatically adjusts the text, to place complete words which overrun at the beginning of the next line. Word splitting and overprinting are therefore eliminated. The cursor indicator assists in displaying the position of characters to be typed or edited.

3.3 Text Editing
Immediate correction of the text can be achieved by three delete keys for character, word or line deletion. The electronic editing program automatically closes up the text to avoid gaps in the message. Complete messages are deleted using the line delete key on the title in the message directory.

3.4 Uninterrupted Off-Line Preparation
If during message preparation an incoming call is received, it is no longer necessary to interrupt the ongoing work. The incoming message is recorded automatically in the memory. A visual indication that an incoming call is being received is given so that the operator may attend the call by pressing the appropriate key if this is desired. The printer is only allocated to an incoming call if the memory is full or the option of immediate print-out has been selected. Once the print-out has teen completed, the message is automatically erased from the memory.

3.5 Fully Automatic Operation
Messages may be transmitted automatically at predetermined times including call initiation, telex number selection, exchange of answerbacks, date and time group insertion, text transmission and automatic cleardown. should a called number be unobtainable,'a number of repeat attempts are made automatically at 2 minute intervals. The exact number of repeat attempts will depend upon the service signal received.

3.6 Abbreviated Calling Codes
An internal directory of 16 frequently used telex numbers can be selected by the user and stored in the memory of the machine. These numbers can then be accessed by operating the 'find' function key followed by a single alpha key (A-P) on the keyboard after depressing the call key.

3.7 Date Time Insertion
Date and time of transmission are automatically inserted into each transmitted message and sent to line. This is additional to the date time group which is locally printed prior to commencing every call record print-out,

3.9 Text Discrimination
Discrimination of transmitted/received/local messages on the printer can be identified by left slanting/right slanting/ upright printed characters. On the screen, discrimination can be identified by received characters appearing brighter than transmitted characters.

3.10 Fault Diagnostics
A central micro-processor controls subsidiary modules with their own micro-processors. This enables the Cheetah to provide specific diagnostic programs for the operator and maintenance engineer.

3.11 Non-Volatile Memory
The Cheetah has a 16K or 32K character non-volatile (by battery back up) electronic memory. Each message is automatically logged with an identification number and title if one has been entered by the operator.

3.12 Paper Tape Attachment
The paper tape attachment is an optional extra and is fitted to the right hand side of the machine. The attachment can be used to input messages to the electronic memory or to produce paper tape from messages already held in the memory, or to send messages to line from tape. See diagram at Appendix 2.

4 MARKETING POLICY
The Cheetah is one of a range of new electronic teleprinters that will be available for connection to the Telex network. . When marketing this teleprinter emphasis should be placed on the advanced facilities offered•by the Machine for -example, integral message store, electronic text editing and visual display screen. In addition, certain features which bring maximum efficiency to message processing, transmission and reception include uninterrupted local operation, automatic deferred calling and many programmable control functions.  A paper tape Attachment is available but the 16K and 32K memory should reduce demand for this item. There will be no restriction on the supply of the Cheetah ie it will be available as new supply or can be provided as change of instrument on existing lines.

4.1 Phased Introduction
The launch programme of the Cheetah will commence initially in BTL and MTR on an Area by Area basis in March 1982. A training programme for Area sales, engineering and telegraph service representatives has been planned for each Region. As the training programme progresses each Region will be individually notified when the Cheetah should be introduced.

4.2 Tariff
The Cheetah will be marketed using a front loaded tariff and a small ongoing quarterly rental. A separate charge will be raised for delivery, installation and customer training. Details of Cheetah charges will be found in BTHQ Circular S1 B8215. Should customer resistance be encountered when advising a potential customer of the front loaded tariff, this may be overcome by explaining that over a rental period of 4 years it will prove more economic than renting current teleprinters. In addition, there are the operational advantages the new teleprinter will provide.

5 SELLING BENEFITS
A summary of the main selling benefits of the new machine are listed as follows:-

• Text editing has been simplified by the word' processing type screen facility which allows letters, words or even whole lines to be deleted at the touch of a single key, and new text inserted wherever required. The electronic editing program automatically closes up the text to avoid gaps, and moves letters from one line to the next to avoid word splitting at line ends.
   

• It is quiet in operation and relatively simple to operate which should enable telex to be brought back to its rightful place, at the centre of the modern office. The machine can be operated on an ordinary desk top, or with the optional plinth.
   

• The integral message stare allows uninterrupted off-line operation, messages can be transmitted or received while others are being prepared. Incoming messages can be stored in the memory until the printer is free, or, the operator gives priority to the incoming message. If the machine is not being used for message preparation, incoming messages appear on the screen as they are being received. This should be a very attractive feature for commodity market users.
   

• A customer entered directory of abbreviated calling codes is provided. It will accommodate 16 frequently called telex numbers together with their answer-backs. Each number is allocated a single character code, when a code is typed, the machine automatically transmits the number, saving operator time and also avoiding mistakes.
   

• The machine can automatically transmit a message stored in its memory at a pre-set time. Should the called number be occupied, up to 5 further attempts will be made before the call is abandoned. It can also transmit the same message to several destinations, Abbreviated calling codes can be used in the auto mode.
   

• Being predominantly electronic with few moving parts, routine preventive maintenance is avoided. The central processor runs continual fault finding checks and in the event of a fault being detected, the machine prompts the operator through routines to identify the nature of the problem.
   

• The non-volatile 16K or 32K memory holds approximately 2250 or 4500 words and enables messages to be stored with little risk of loss and without the need of paper tape. Messages can be held in the memory for as long as necessary. When required, messages can easily be retrieved for transmission or editing.

6 DIMENSIONS

TELEPRINTER
Height 326 mm
Width 590 mm
Depth 600 mm
Weight 23 kg

PLINTH
Height 650 mm
Width 706 mm
Depth 570 mm
Weight 12 kg