In part 97 the FCC specifies bandwidths of 20 and 100 kHz on VHF and UHF bands and this is defined as 26dB below the mean power level. That hasn't prevented hams from designing and building their own gear for 6 m through 70 cm. I'm assming the FCC will want similar standards as they are more concerned with adjacent channel interferce than the width of the desired signal.
73, John KD6OZH ----- Original Message ----- From: jgorman01 To: digitalradio@yahoogroups.com Sent: Saturday, December 29, 2007 13:49 UTC Subject: [digitalradio] Ham Radio ALE High Frequency Network (Re: FCC to Kill Digital Radio?) One problem with your scenario is that the petition uses necessary bandwidth for data emissions, you are describing occupied bandwidth for phone/image emissions. From a practical standpoint there is a BIG difference in determining the two. Data emissions are nice because their parameters are very well defined or you won't be able to communicate. Things like number of tones, separation of tones, phase shift values, frequency shift values, etc. All of these combine to allow EVERYONE to obtain the same value through the necessary bandwidth calculations. Developers can set their parameters so that the necessary bandwidth is 1500 Hz and no problem. Measuring occupied bandwidth for phone/image emissions is a totally different matter. This WILL limit experimentation because only a few amateurs can afford adequate spectrum analyzers and understand how to use them. You will also end up with bandwidth cops filing complaints that Joe Blow is 100 Hz too wide and should receive an enforcement letter to take him off the air. Jim WA0LYK --- In digitalradio@yahoogroups.com, W2XJ <[EMAIL PROTECTED]> wrote: > > Point well taken, provided that is how the rule is actually written. > > > > > John B. Stephensen wrote: > > I used 8 kHz because the FCC will specify the maximum bandwidth at -23 dB. Users want 6 kHz minimum bandwidth with minimal attenuation. Maufacturers of ham radio equipment usually specify the bandwidth of a 6 kHz crystal filter at the -3 dB points and the tolerance is often -0% / +25%. AM and phasing SSB transmitters have audio low-pass filters that roll off at 30-42 dB per octave. > > > > 73, > > > > John > > KD6OZH > > > > ----- Original Message ----- > > From: W2XJ > > To: digitalradio@yahoogroups.com > > Sent: Saturday, December 29, 2007 08:45 UTC > > Subject: Re: [digitalradio] Ham Radio ALE High Frequency Network (Re: FCC to Kill Digital Radio?) > > > > > > I would almost agree except for the 8 kHz wideband mode. That can easily > > be 6 kHz and accommodate AM as used in HF communications. A wider > > bandwidth just opens the door to more problems. I will file my comments > > based on yours except I will suggest a maximum of 6 kilohertz. > > > > John B. Stephensen wrote: > > > An ALE network and WinLink are both useful. My comments to the FCC were: > > > > > > "RM-11392 attempts to address problems of interference between narrow > > > and wide bandwidth text and data communition modes on amateur > > > bands, but the proposed rule changes will create more problems than > > > they solve. Historicly, communication in the amateur radio service > > > was either narrow-band (100-500Hz) text or wideband (2-7 kHz) voice > > > and each fequency band was partitioned into 2 segments. These were > > > originally for cw and phone, but now are rtty/data and phone/image. > > > > > > With the arrival of digital modulation techniques text, images and > > > voice may be transmitted alternately or simultaneously using the > > > same modulation method and with various occupied bandwidths. The > > > best solution for the future and the one that minimizes regulatory > > > burdens on both users and the FCC is to redefine these band > > > segments as being for narrow-band and wide-band emissions > > > regardless of content (voice, image, text or data). > > > > > > In my view, the optimal maximum bandwidths for frequencies below 29 > > > MHz are 800 Hz at for the narrow-band segments (usually the lower > > > frequencies in each band) and 8 kHz for the wide-band segments > > > (usually the higher frequencies in each band). 800 Hz allows for CW, > > > RTTY, PSK31, MFSK16 and other modes used for keyboard-to-keyboard > > > comunication and slow-speed image communication and file transfer. 8 > > > kHz is consistant with limits in other countries (when they exist at > > > all), allows existing AM stations to continue to operate and allows > > > simultaneous voice/text/image communiation using analog or digital > > > modulation. > > > > > > A small area (10-20 kHz) for automated stations must also be > > > established in the wide-band segments of HF bands to allow for > > > PACTOR-3 and similar protcols used for message forwaring as they > > > are invaluable during emergencies where the normal communications > > > infrastructure is compromised. > > > > > > If the rule changes are to extend beyond 29 MHz, maximum bandwidths > > > of 20 kHz should be adopted between 29 and 29.7 MHz and 200 kHz > > > between 50 and 225 MHz for the old phone/image segments. This allows > > > for exsting FM voice and medium-speed data stations in the 10, 6, 2, > > > and 1.25 meter bands. Any bandwidth limits above 420 MHz must be > > > 25 MHz or greater to accomodate existing stations using IEEE 802 > > > data trasmission and AM and FM TV. In my opinion, no bandwidth > > > limits are required above 420 MHz as long as emissions stay within > > > the designated bands for the amateur radio service. > > > > > > The rules changes outlined above should solve several problems and > > > decrease regulatory burdens in the future." > > > > > > 73, > > > > > > John > > > KD6OZH > > > > > > ----- Original Message ----- > > > From: expeditionradio > > > To: digitalradio@yahoogroups.com > > > Sent: Saturday, December 29, 2007 07:16 UTC > > > Subject: [digitalradio] Ham Radio ALE High Frequency Network (Re: FCC to Kill Digital Radio?) > > > > > > > > > The Ham Radio ALE High Frequency Network (HFN) > > > http://www.hflink.com/hfn/ > > > is the only HF 24/7 network on ham radio that can be accessed and used > > > for text messaging without an external computer or modem. HFN may also > > > be used with a regular HF ham radio and a laptop or PC computer > > > soundcard using one of several free ALE software programs. > > > > > > Ham Radio ALE High Frequency Network (HFN) would cease to exist if any > > > of the objectives of FCC RM-11392 petition were to succeed. > > > > > > HFN covers all of North America, and other parts of the world. > > > All HF bands. > > > All day. > > > All night. > > > > > > see map: > > > http://hflink.com/HFN_PILOT_STATION_MAP1.jpg > > > > > > HFN operates within FCC rules in the Automatically Controlled Data > > > Station HF Sub Bands... see chart: > > > http://hflink.com/bandplans/USA_BANDCHART.jpg > > > > > > The HFN system uses International Standard ALE (8FSK, with 2.2kHz > > > bandwidth) for selective calling, nets, bulletins, data, HF-to-HF > > > relay, direct text messaging, HF-to-Cell Phone texting, and short text > > > e-messaging. > > > > > > The primary purpose of HFN is to provide Emergency / Disaster Relief > > > Communications. When the system is not being used for the primary > > > purpose, it provides normal daily routine text messaging services, > > > propagation services, and many other types of features for hams. > > > > > > HFN ALE stations use a common frequency per band, sharing the same > > > "channel" on a time-domain multiplexed basis, with a combination of > > > automatic busy detection and/or collision detection systems. The > > > transmissions are normally sent in quick bursts. > > > > > > The system is free and open for all ham radio operators... > > > for more information about using HFN, click here: > > > http://www.hflink.com/hfn/ > > > > > > The Ham Radio ALE High Frequency Network does not require the internet > > > to function, but it uses the internet when it is available. It is the > > > only ham radio system of its kind that is truly interoperable on HF > > > for selective calling, voice, and text, with other non-amateur > > > services and agencies. For more information about this, see > > > Interoperable HF Communications: > > > http://www.hflink.com/interoperation/ > > > > > > Who among the "anti-automatic" and "anti-everything-that-is-not-PSK31" > > > hams are going to volunteer to replace the HFN if it were to be killed > > > by this petition? > > > > > > Please show us your alternative 24/7/365 manually operated system on HF. > > > Show us how you will monitor all HF ham bands simultaneously and > > > respond instantly. > > > > > > When will you sleep? How many hams will work 8 hour shifts every day? > > > How will we alert you on HF to run emergency traffic? Will you answer > > > the call? > > > > > > It is time for those who seek to put us back to the digital stone age > > > to step up to the plate and put their money where their mouth is. > > > > > > Happy New Year! > > > > > > 73 Bonnie KQ6XA > > > > > > . > > > > > > > > > > > > > > > > > > > > >
