During a QPSK QSO with G3PLX the originator of PSK31 today, he pointed out that my signal did not include about a second of centre-frequency CW at the end of transmission, with the result that his demod was displaying some garbage characters at the end of my transmission. The CW "postamble" tells the demod that the transmission has finished and to tidy up cleanly.
The fldigi demod appears to work correctly: if the centre-frequency postamble is received no garbage characters are displayed, but if the transmission is abruptly stopped while in the two-tone idle state random characters are shown, as expected. Checking the fldigi QPSK output on a monitor receiver here confirms that a two-tone rather than single-tone postamble is sent for all QPSK variants. BPSK is fine and sends the single-tone postamble as expected. -- Peter G4VLC _______________________________________________ fldigi-alpha mailing list [email protected] https://lists.berlios.de/mailman/listinfo/fldigi-alpha
