> k2ncc asked: > ...is it legal to transmit on the digital modes > sub-bands modes that are greater than 1000 wide, > like Olivia 2000?
Yes. Under the present "content-based" rules for hams in USA, FCC has confirmed that there isn't really a specific bandwidth limit for most types of modern digital data signals on HF... other than the maximum limit of the "RTTY/data subband" segment... for example, on 20 meters, hams in USA can legally transmit a 150kHz bandwidth data signal (14100kHz to 14150kHz). See the FCC order May 7, 2008 denying the "Digital Stone Age" petition: http://www.hflink.com/fcc/digitalstoneage/FCC_denies_digital_stone_age_petition.PDF In that FCC order, [paragraph 10] FCC said: "Our rules do not specifically limit the permissible bandwidth for RTTY and data emissions in the amateur HF bands." FCC explained [paragraph 10] further: "We believe that these rules provide amateur service licensees the flexibility to develop new technologies within the spectrum authorized for the various classes of licensees, while protecting other users of the spectrum from harmful interference. We also believe that imposing a maximum bandwidth limitation on data emissions would result in a loss of flexibility to develop and improve technologies as licensees' operating interests change, new technologies are incorporated, and frequency bands are reallocated." 73 Bonnie KQ6XA
