[RTTY] uh, what about spectrum?

[Michael Keane K1MK]

At 11:10 PM 1/15/06, Mike <k4gmh at arrl.net> wrote:

>   Since I use 170 Hz shift (bandwidth) and the DX stations I have
>contacted in and out of contests are also 170 Hz shift, the ARRL
>proposal should not impacting my operation in the 3520 - 3525 KHz
>area and below 7030 KHz and below 3580 KHz.  Am I not reading it
>correct?  Is there another ARRL or FCC document/proposal I should be
>looking at?

The petition for rulemaking 
<http://gullfoss2.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdf&id_document=6518181567> 
defines bandwidth to be the necessary bandwidth as that term is 
defined in Part 2 of the FCC rules.

Section 2.202 of the FCC rules specifies that the necessary bandwidth 
of an FSK signal is equal to 1.2 x Shift + BaudRate. Under this 
proposal a 45 baud RTTY signal at 170 Hz shift would be considered to 
have a bandwidth of 249 Hz by rule.

So yes, under the proposal US stations would not be allowed to 
transmit RTTY in the 3520-3525 KHz area or below 7030 KHz or below 
3580 KHz. That the rulemaking petition chose 200 Hz and not 250 Hz or 
300 Hz  was not entirely arbitrary.

73,
Mike K1MK

Michael Keane K1MK
k1mk at alum.mit.edu