SCS PTC-IIex, Manual

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6 Commands
may be the correction parameter to the hardware clock in ppm (Quartz). For example, a
system clock running 10 ppm too fast can be compensated by typing -10. The entered
correction parameter becomes valid when the next PACTOR contact is started. During
slave mode, the PTC software automatically issues the appropriate phase correction
setting, so that exact synchronization between the master and slave station will be
established within a few minutes after start of the contact, provided the initial clock
difference did not exceed 30 ppm. When called without an argument, the actual total
phase correction, manually and system-generated initial values, are displayed.
This is a powerful feature that you can use for aligning your PTC crystal oscillator,
without any measuring instruments, following these steps. Perform a master call to a
station with a known highly accurate PTC clock
frequency . After at least five minutes of
contact, you can read out the phase correction data from the reference station, by sending
a remote control P command. Enter the phase correction data from the reference station as
a new initial value for the Phase command,
inverting the preceding factor (i.e. '-78'
becomes '+78'). If a timeout occurs under 5 minutes, your system clock offset is probably
too great to be compensated by the automatic phasing. In this case, the data readout will
only show a tendency.
6.72 POSition
Remote
Default setting: none
Parameter: NMEA Requests NMEA raw-data.
When a GPS receiver is connected to the PTC-IIex, its possible to readout the actual
position using the
POSition-
command. The position information normally has the
following format:
GPS POSITION REPORT
-------------------
Latitude: 50° 05.430' North
Longitude: 008° 45.980' East
Velocity: 0.0 Knots
Course: 360°
Recorded at: 13/12/00 19:25:48 UTC/GMT
The
POSition
command allows the argument NMEA.
cmd:
POS NMEA
<Return>
The PTC-II in this case gives out the original NMEA compatible position string
("sentence") - exactly as it was received from the GPS receiver. NMEA compatible
strings are "understood" by various navigational programs, and can thus be almost
universally used. The NMEA compatible position string usually has the following format:
$GPRMC,212234,A,5005.432,N,00845.974,E,000.0,360.0,190201,000.1,E*7B
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