Specifications

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RFRame ON|OFF Default: OFF
Mode: Baudot and ASCII RTTY Host: RG
_________________________________ Parameters: __________________________________
ON - Check received Baudot and ASCII characters for framing errors.
OFF - Print received Baudot and ASCII characters regardless of errors.
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When RFRAME is OFF (default), Baudot and ASCII modes operate as always, that is
characters are copied based on the presence of the DCD signal.
When RFRAME is ON, the PK-900 checks received Baudot and ASCII characters for
framing errors. A framing error on a character in an asynchronous mode
(such as Baudot and ASCII) occurs when the bit in the stop position is detected
to be the wrong polarity (the polarity of the start bit is supposed to be space
or 0, while the stop bit is supposed to be mark or 1). The unit stops copying
characters when 4 out of the last 12 characters had framing errors. Copy
resumes when the most recent 12 characters are error-free. This should
significantly reduce the copying of garbage characters when no signals are
present. When RFRAME is ON, characters are copied based on the recent history
of framing errors.
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RXRev ON|OFF Default: OFF
Mode: Baudot and ASCII RTTY/AMTOR Host: RX
_________________________________ Parameters: __________________________________
ON - Received data polarity is reversed (mark-space reversal).
OFF - Received data polarity is normal.
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Use the RXREV Command to invert the polarity of the data demodulated from the
received mark and space tones.
In some cases, you may be trying to copy a station that's transmitting "upside
down" although it is receiving your signals correctly. This is especially true
when listening to signals in the Short Wave bands. Set RXREV ON to reverse the
data sense of received signals.
Although RXR will reverse the mark and space polarity in PACTOR, the mode is
polarity insensitive so RXR will have no effect.
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