Which sequence best describes a complete ARQ TELEX exchange with a coast station?

Which sequence best describes a complete ARQ TELEX exchange with a coast station?

• A. Initiate call, observe phasing, send message, terminate link
• B. Initiate call, observe phasing, send DIRTLX command, send message
• C. Initiate call, observe answer-backs, send message, terminate radio link
• D. Initiate call, observe phasing, exchange answer-backs, send message

Answer: (B)

The correct sequence for a complete Automatic Repeat reQuest (ARQ) Telex exchange with a coast station involves initiating the call, observing phasing, sending the DIRTLX command, and then sending the message. Initiating the call is the first step, where the station establishes a communication link with the coast station. Observing phasing allows the operator to confirm that the circuit is ready for transmission. The DIRTLX command is specially used in the ARQ system for the transmission of messages over telex networks, serving to set the parameters for the communication, which is crucial for ensuring that the subsequent message is sent correctly and reliably. Finally, sending the actual message is the last step, completing the communication. This sequence clearly delineates the steps necessary to engage in an ARQ Telex exchange, focusing on the unique role of the DIRTLX command to facilitate the message transfer.

The correct sequence for a complete Automatic Repeat reQuest (ARQ) Telex exchange with a coast station involves initiating the call, observing phasing, sending the DIRTLX command, and then sending the message.

Initiating the call is the first step, where the station establishes a communication link with the coast station. Observing phasing allows the operator to confirm that the circuit is ready for transmission. The DIRTLX command is specially used in the ARQ system for the transmission of messages over telex networks, serving to set the parameters for the communication, which is crucial for ensuring that the subsequent message is sent correctly and reliably. Finally, sending the actual message is the last step, completing the communication.

This sequence clearly delineates the steps necessary to engage in an ARQ Telex exchange, focusing on the unique role of the DIRTLX command to facilitate the message transfer.