CIS-36-50

CIS-36-50, also known as BEE-36 or T600, is a synchronous system. Usually a 36 Bd idle sequence is transmitted, followed by 50 baud traffic.

Parameter

Value

Frequency range

VLF, HF

Operation modes

Simplex

Modulation

FSK

Symbol rate

36, 50, 75, 100, 150 Bd

Shift

 

85, 125, 250 and 500 Hz, variable 50-3500 Bd

Receiver settings

DATA, CW, LSB or USB

Input format(s)

AF, IF

All traffic is encrypted.

A message begins with a bit synch sequence and a start-of-message preamble. Message data is sent with a 7-bit, 3:4 ratio alphabet, and ends with an end of transmission sequence containing at least 4 end-of-transmission characters.

The length of a message is variable. If a transmission contains more than one message, the start of message sequence is left out between messages.

Occasionally traffic with call signs in FSK CW is transmitted.