Bulletins from the Pacific Packet Radio Society - page 092

with respect to permitted teleprinter codes. The instant request would also grant to amateurs a tool of potentially vital importance in emergency communications. The savings in time and increase in accuracy in transmission of message traffic during emergencies allowed by the error-correcting characterestics of AMTOR operation make the public benefit of the instant request facially obvious.

Technical Specifications as Contained
in CCIR Recommendation 476-2 Should
be Adopted to Facilitate Monitoring

9. The Commission has recently proposed 8/ in PR Docket 81699 the amendment of Section 97.69 of the Rules to permit the use of any digital encoding technique in the amateur frequency bands above 50 MHz. That proposal, if adopted, would permit the use of AMTOR on frequencies above 50 MHz. The instant proposal, therefore, proposes the use of AMTOR only on amateur high frequency bands where Baudot and ASCII emissions are permitted. 9/

10. When the Commission authorized the use of ASCII in 1980
10/ it stated that:

Past experience with the use of Baudot Code in the Amateur Radio Service indicates that the vast majority of operators use common radioteleprinter standards, thus simplifying enforcement monitoring both by amateurs and our monitoring personnel. Thus, we a re not adopting any further standards \other than maximum sending speeds}.

Beyond specifying in detail the transmission code to be used, CCIR Recommendation 476-2 sets forth precise specifications for transmission speed (100 baud), carrier shift (170 Hz) and block timing (0.45 second) . Successful AMTOR operation depends upon nominal crystal stability of the transmission rate and block timing at both sending and receiving stations. An obvious question is presented as to whether these standards should be adopted as rules or whether, as in Docket 20777 pertaining to ASCII, only a maximum sending speed applicable to each band need be specified. So that no question should arise as to content monitoring difficulties by amateurs and Commission enforcement personnel, and to assure full compliance with Article 41 of the International Radio Regulations, 11/ it is proposed that the standard transmission speed and block timing be adopted exactly as specified in CCIR Recommendation 476-2 in the proposed amended Rule Section 97. 69. The transmitter frequency shift may be simply limited to "less than 900 Hz," as is presently required in Section 97.69(a)(3) for Baudot transmissions . The attached Appendix sets forth the proposed rule amendments.


11 . The proposed rule change will continue the Commission's

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