SCS PTC-IIex, Manual

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6 Commands
The block number count enables external software for example, to perhaps recognize any
block loss that may occur during data transfer, and in such an event, to undertake damage
limitation measures. Such measures may, for example, replace the missing block by an
empty block.
<CR> or <LF> can generally be completely ignored, so that there should occur no
problem due to incompatible terminal programs. The read algorithm by the PTC
RELOad
synchronizes only with the help of the S start character.
6.9 BAUdot
Default setting: 45
Parameter: X 20 to 300 Baud.
Switches to RTTY with the given baud rate. E.g.
BAU
100 switches to RTTY with 100
baud. The baud rate is continuously variable between 20 and 300 baud.
The baud rate can be exactly set, without quantization problems, because an interpolation
algorithm is used. The computer also automatically calculates the best low pass filter for
the baseband filtering according to the baud rate. This gives excellent receiving
characteristics, that hardly vary from the theoretical ideal value.
After
BAU
, the PTC answers with:
>>> BAUDOT--RTTY RECEPTION ACTIVE -- SPEED: 45 BD <<<
and is ready to receive RTTY transmissions.
Changing to transmit is done with the CHANGEOVER character (set with the
CHOchr
command, refer to chapter 6.19 , page 44 ). Changing to receive again is done with the
QRT character (set with the
QRTChr
command, refer to chapter 6.78 , page 70 ).
Directly after activating RTTY with
BAU
, the PTC is in Converse mode i.e. all entered
characters are send to the transmission buffer. This has the advantage that text can be
typed ahead. During the other station's transmission, it is possible to type in the station
description or other message, for example a welcome. After switching to the transmit
mode the text will be sent immediately.
To enter a command to the PTC, an ESC character (defined with the
ESCchr
, refer to
chapter 6.39 , page 54 ) must be given first. In RTTY mode, the AMTOR-prompt is in the
form of:
**--R--** (DFCJ):>
After approximately 4 minutes of idle transmissions, an automatic QRT is carried out!.
6.10 BC
Default setting: 1
Parameter: 0 FEC reception disabled.
1 FEC reception enabled.
AMTOR FEC and NAVTEX reception is disabled or enabled. If
BC
=1 the PTC will
receive AMTOR FEC transmissions in the STBY mode.
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