SCS PTC-IIex, Manual

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6 Commands
The cycle time increases to 1.4 seconds and the control delay becomes long enough for
ARQ contacts to over 40,000 km (TRX-Delay 25 ms). PTC1 systems (Z80-PTC) with a
firmware version number <1.3 are not able to detect syncpackets with long path options
and don’t react on long path calls. During connections using the long path option the
throughput decreases to approximately 90% of the usual throughput.
If the long path option was used for last PACTOR connection or the last MASTER
connect attempts (exclamation mark before the callsign), all of the following
Connect
commands without an argument will start a call using the long path option.
6.22.2 Robust-Connect
The PACTOR-II robust connect procedure Robust Connect allows reliable link
establishment even under extremely poor and difficult signal conditions. Up to firmware
version 3.1, the
Robust Connect has only been available as a part of the Professional
PTC-IIex firmware. With version 3.1 Robust Connect will also be available as a part of
the "normal" firmware, but restricted to outgoing calls/connects, i.e. only systems
equipped with the Professional Firmware (also known as Marine Firmware ) are able to
accept Robust Connect frames:
Two PTC-II's both running the "normal" Firmware cannot mutually connect using the
Robust Connect since only the Professional Firmware is capable of receiving and
accepting Robust Connect frames. As opposed to the Professional Firmware , the
"normal" firmware will not recognize incoming Robust Connect frames. On the other
hand it can generate outgoing Robust Connect frames and thus initiate a link using the
Robust Connect procedure if the remote system runs the Professional Firmware .
A
Robust Connect can be started by prefixing the call sign (argument of a connect
command) of the distant system with a "%" sign, e.g.:
cmd:
C
%DL1ZAM <Enter>
This is also valid for WA8DED hostmode. In terminal mode the PTC-II(e) will respond
as following:
*** NOW CALLING DL1ZAM (ROBUST CONNECT)
In case of a connect command without argument, the PTC-II automatically inserts the call
sign used by the remote system during the latest connection. If the link was initiated by
the PTC-II itself and the
Robust Connect procedure was utilized, the PTC-II will not only
insert the call sign but also automatically add the %-sign and thus re-invoke the Robust
Connect procedure.
The Robust Connect uses "normal" PACTOR timing. Longpath option and Robust
Connect cannot be combined! The call sign of the remote station may only be prefixed
by "%" OR "!".
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