ยง 97.307 Emission standards. (a) No amateur station transmission shall occupy more bandwidth than necessary for the information rate and emission type being transmitted, in accordance with good amateur practice.
(f)(2) No non-phone emission shall exceed the bandwidth of a communications quality phone emission of the same modulation type. The total bandwidth of an independent sideband emission (having B as the first symbol), or a multiplexed image and phone emission, shall not exceed that of a communications quality A3E emission. Why do you chose 3 kHz. The FCC recently issued a ruling NOT LIMITING SSBSC to 3 kHz. This allows advancement of the radio art in using SSBSC transmissions out to 4.5 kHz, or as some say ESSB. I would imagine an image transmission could use this bandwidth also, assuming you were using 4.5 kHz for the SSB part of your transmission. Paragraph (a) simply says "information rate and emission type". I don't see a specific limitation here. In addition, (f)(2) allows ISB or multiplexing to go out to 9 kHz, i.e. A3E. Again, I don't see any 3 kHz restriction. If you mean you can't use your plain old off the shelf commercial SSB rig for ISB or multiplexed audio/image, then there is a problem, but it isn't the regulations, it is your rig. Keep in mind, the bandwidth petition would have eliminated these options and made you stay within 3 kHz! Lastly, you are mixing content restriction problems with bandwidth restrictions. If content regulation is needed then that can be addressed without bandwidth restrictions. Jim WA0LYK --- In digitalradio@yahoogroups.com, "John B. Stephensen" <[EMAIL PROTECTED]> wrote: > > 47cfr97.307(f)(2) limits the bandwidth of all transmissions in the phone/image segments to that of AM or SSB communications quality audio which is usually interpreted as 3 kHz. There is nothing allowing data (computer communications) or RTTY (direct printing telegraphy) in the phone/image segments. Unfortunately, image is defined as facsimile and television. > > 73, > > John > KD6OZH > > ----- Original Message ----- > From: jgorman01 > To: digitalradio@yahoogroups.com > Sent: Tuesday, May 01, 2007 20:56 UTC > Subject: [digitalradio] Re: ARRL wake up ...... > > > Can you give me a regulation that restricts very wide modems within > the phone/image segments. If you are talking about using data in the > phone/image segment, I'll agree but I don't see a paragraph that > limits bandwidth within the phone/image segment. > > I will agree that wider bandwidths could be allowed on the 70cm band. > Wonder why a petition wasn't filed that dealt with this issue only. > > Jim > WA0LYK > > --- In digitalradio@yahoogroups.com, "John B. Stephensen" <kd6ozh@> > wrote: > > > > One problem is that very wide modems are allowed only outside the > phone/image segments, which is the opposite of what is reasoable for > users. Another example is that data modes are only allowed a 100 kHz > bandwidth on 70 cm which is 30 MHz wide. > > > > 73, > > > > John > > KD6OZH >
