Wavecom W61PC V7.5.0 - Manual (Page 124)

114  Transmission Modes WAVECOM Decoder W61PC/LAN Manual V7.5
however no transmissions with sub-channel division are known. Systems employing sub-channel division
may be recognized by the rhythmic blinking of the Error indication (system state) in the decoder status
bar.
ARQ-N
ARQ-N uses the ARQ-1A alphabet (as does ARQ-E). Character inversion (as in the case of ARQ-E or ARQ-
E3) is not defined for ARQ-N. The lack of inversion makes it impossible to automatically determine the
length of the RQ cycle. However, known systems operate exclusively with a single RQ character and three
repeated characters.
Parameter Value
Frequency range HF
Operation modes Duplex ARQ
Modulation FSK
Symbol rate 48, 64, 72 86, 96 and 192 Bd, variable 30-650 Bd
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
Additional Info ITA-2 with parity and identification bit
Known ARQ-N systems operate exclusively at a symbol rate of 96 Bd on the radio link.
The synchronization phase for the ARQ-N mode of operation may be initiated via the AUTO function or by
manual selection of the baud rate.
Signal polarity (USB or LSB sidebands) is automatically detected.
Full-duplex systems transmit the RQ character after having detected an erroneous character or in the
presence of excessive signal distortions. The remote station subsequently repeats the last three characters
preceded by the RQ character.
To maintain synchronization between the two stations both transmitters operate continuously and send
the idle bit pattern if no traffic data is transmitted.
ASCII
The ASCII code, which is internationally adapted as the CCITT ITA-5 alphabet, is used in all kinds of data
transfer of information between computers or computer based equipment. Only the 7-bit values 0 – 127
are internationally defined and standardized. For asynchronous transmissions, the code consists of a start
bit, 7 or 8 data bits, one parity bit (optional) and 1 or 2 stop bits.
Parameter Value
Frequency range HF
Operation modes Asynchronous
Modulation FSK
Symbol rate 50, 75, 100, 110, 150, 180, 200, 300 and 600 Bd, variable 50-1200 Bd
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
Additional Info ITA-5
For ASCII mode standard baud rates from 110 to 300 Baud are available. Non-standard baud rates may
be selected using the Baudrate menu item.