[RTTY] Error in RM-11708

Joe Subich, W4TV lists at subich.com
Wed Nov 27 01:17:15 EST 2013


The entire premise of RM-11708 is flawed.  There *is* a limit on
occupied bandwidth for digital modes at HF.  That limit is found
in the very definition of "data" - see section 97.3(c)(2) which
reads:

> (2) Data. Telemetry, telecommand and computer communications
> emissions having (i) designators with A, C, D, F, G, H, J or R as
> the first symbol, 1 as the second symbol, and D as the third symbol;
> (ii) emission J2D; and (iii) emissions A1C, F1C, F2C, J2C, and J3C
> having *an occupied bandwidth of 500 Hz or less* when transmitted on
> an amateur service frequency below 30 MHz.  Only a digital code of
> a type specifically authorized in this part may be transmitted.

[54 FR 25857, June 20, 1989]

Where "data" is listed as an authorized emission type in section 97.305
for *any* frequency below 30 MHz, "data" carries the limitation from
97.3(c)(2).

Based on this, ARRL is not asking for a limit where none presently
exists - they are proposing a *massive increase* in permitted bandwidth
with no justification.  Further, it would appear that PACTOR III and
its 2200 Hz bandwidth is actually illegal and ARRL should be asking the
Commission to enforce the current rules - not reward those who continue
to flaut them.

73,

   ... Joe, W4TV



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