Practical HF Digital Voice
نویسنده
چکیده
[Editor’s note: We goofed! The transmission of telephony in digital format (emission designator J1E or J2E) is perfectly legal in the phone bands. The restriction placed on transmitted baud rate by §97.307(f)(3) of the FCC rules does not apply. In fact, there is no upper limit on the bit rate for this mode. See the sidebar by ARRL Technical Relations Manager Paul Rinaldo, W4RI. Some of this material is from Charles’ paper in the Proceedings of the 18th ARRL/TAPR Digital Communications Conference, some from Andy’s paper in RadCom, March 1999.] This whole project began with a conversation over the telephone: Andy said that it would be fun to transmit “real-time” digital speech on the amateur bands. Now there was a challenge! As he is located some 70 km
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