Telex World Letter - A 1980's Speedy Letter Delivery System

MCI International launched its Telex World Letter service in about 1986

MCI filed the Telex World Letter trademark in 1986, likely the same year the service was introduced.

MCI International – Creators of the Telex World Letter

Telex in the UK and Teleprinters I Remember

Teletex System of Document Transfer Abandoned in The 1990s

Drawing from personal experience, I remember using this service as a telex operator in the late 1980s. At that time, the Telex World Letter stood out as an innovative method to send a letter from a telex machine, ensuring worldwide delivery free of charge, courtesy of MCI International.

While delivery was free for recipients, telex subscribers paid the connection fee to MCI International in the USA.

This leads to the question: How was a Telex World Letter actually sent?

To send a Telex World Letter, the operator would connect to MCI International’s USA server by dialling telex 666400. Upon receiving the MCI TELEX WORLD LETTER answerback, MCI’s server would automatically capture the originating machine’s answerback, enabling communication.

Then, when communicating with MCI’s computer, operators had to follow strict message formatting, as detailed in my adapted MCI International instructions below.

An example of how a Telex World Letter would have been formatted

System Prompt

Operator Response

MCIWORLD LETTER
YOUR ANSWERBACK

IS HELP DESIRED?

NO (CR)

LETTER NUMBER: 100/2
(system-generated)

TO:

JOHN SMITH (CR) (LF)

COUNTRY OF DESTINATION

ENGLAND (CR)

ADDRESS LINE 1:

NAME OF COMPANY (CR) (LF)

ADDRESS LINE 2:

022 FLEET STREET (CR) (LF)

CITY:

LONDON (CR)

**STATE: (OR PROVINCE:)

**ZIP CODE: (OR POSTAL CODE:)

EC4Y 000 (CR)

YOUR NAME:

JOHN SMITH (CR)

YOUR COUNTRY:

USA (CR)

YOUR TELEX NUMBER:

000000 (CR)

START OF MESSAGE:

YOUR MESSAGE (CR)

END OF MESSAGE SIGNAL:

MMMM (CR) (LF)

Further input options were available. For instance, it was possible to send multiple messages during the same connection. For more information, please view the source document and click or tap the link titled “DOWNLOAD PDF”.

CR is short for carriage return. LF is short for line feed. Telex machines sent and received messages using capitalised letters.

Further reading: View an MCI International advertisement for the Telex World Letter. PDF file.