Tony > On Sep 2, 2017, at 04:16, Mark Phillips &lt;g7ltt(a)g7ltt.com&gt; wrote: > > "3.) Develop a data mode that uses multiple carriers, as each carrier > can be 100 KHz wide." > > We have that already. That's kinda how OFDM and COFDM work but with smaller > bandwidth carriers. Indeed, many of the HF sound card data modes work that > way too. So if someone with clever programming skills can work out how to > bodge up PSK256K and shove it into the back of a Moto SM50 we might be on > to a winner. > > But there are still some hardware solution out there too that need to be > investigated. The CM589 modem chip that D-STAR uses (found in AIS rigs too) > can do up to 256K. Why have we not got an Arduino based modem that accepts > this chip and allows us different speeds? I've also asked the MMDVM crowd > to look at converting their modem stuff to higher speed packet (they said > "what's packet?"). > > I'm full of ideas but lack any skills to implement anything. > >> On Sat, Sep 2, 2017 at 9:50 AM, Steve L &lt;kb9mwr(a)gmail.com&gt; wrote: >> >> While I applaud Ron's experiments, it would have a very long road to >> becoming something practical for the masses. Heck I can say the same >> for the NWDigital radio. They have been trying for quite some time to >> make the thing happen. I fear by the time either would come to >> fruition, the whole market / tech landscape could be different. (I.e, >> 56k is not as appealing at the price point as it was 10 years ago when >> they started, etc) >> >> As for the ARRL, I am the only one who pounces on their staff >> virtually every chance I get (at ham fests and by email), about >> getting some of these changes though their heads? I think a >> coordinated approach, can help our cause. In addition, anyone can >> make comment directly to the FCC. How seriously they take things >> without someone waving money in their face is a whole another issue. >> >> I wrote this paper quite some time ago, that covers quite a few of the >> issues: >> http://www.qsl.net/kb9mwr/projects/wireless/70cm-ATV-HSMM.html >> >> Basically they way I see it, one has three ways to experiment: >> 1.) Pay for/file for a STA, which gives you 6 months >> 2.) Include some element of image transfer, so what your doing can be >> classified as an image transmission rather than data. (most >> logical/easiest to do) >> 3.) Develop a data mode that uses multiple carriers, as each carrier >> can be 100 KHz wide. >> >> #3 is something I joked with friends about when I was in high school. >> That was long before SDR, so we envisioned taking a few TNC's and >> radio's on different frequencies, RF combiners and tons of filters to >> make it actually work, and from there channel bond/load balance all >> the data streams to achieve better throughput. >> >> Do we have anyone who holds a ARRL position on this list? >> >> >> Steve, KB9MWR >> >> Mark Phillips <g7ltt at g7ltt.com> wrote: >>> >>> "Maybe someone at ARRL ...." >>> >>> Ha! Funny. >>> >>> It's been many folks' experience that the ARRL does nothing that is not in >>> its own interest. Unless they can be persuaded that XYZ technology is good >>> for them and Ham Radio they won't lift a finger. It should also be noted >>> that the ARRL speaks for less than 20% of the US ham population (see >>> membership figures posted in QRZ). We are 700K+ hams here in the US. ARRL >>> has less than 100K members. That said, they are the only group able to >>> engage the FCC and push for changes etc. It's an expensive proposition! >> _________________________________________ >> 44Net mailing list >> 44Net(a)hamradio.ucsd.edu >> http://hamradio.ucsd.edu/mailman/listinfo/44net >> >

On Saturday, September 2, 2017 9:21:45 AM PDT Brian Kantor wrote: The problem with the GRAPES modem was cost, the kit was reasonable but add in all the other pieces and it was more than many of us could afford. We had a few GRAPES modems here in the Pacific Northwest but very few ever made it on the air. We did have a dedicated 56k link over an 80 mile path between Camano Island north of Seattle and a 56k repeater on Mount Seymour in British Columbia. The repeater and the link radio used a 56k modem designed by Dennis, AC7FT (then VE7BPE). It was compatible with GRAPES but was a completely separate design. That link provided additional connectivity for the 1200/9600 IP network in central Puget Sound for several years and was reasonably reliable. Those were fun times -- Ken - N7IPB Email: n7ipb(a)wetnet.net JID: n7ipb(a)jabber.wetnet.net PGP Sig: F42B EF90 3CD3 31C7 3056 122E 993A 7B2E 5138 C42A Life isn't like a bowl of cherries..... It's more like a jar of jalapenos. What you do today is likely to come back and burn you in the butt tomorrow.

I think you're wrong. Well, actually, I know it! ;-) Very few, if any, hams that I know would have any interest in the kit you mentioned. Including me. Far too much work. Too costly. Far too complicated for the average one-day ham-cram technician-class, appliance operator ham. So even if a few might be willing to do the work to put those at the "server" location(s), you won't have many/any? "clients". In contrast, we've had about 30 or so folks waiting for an appliance-like device, such as the NWD UDRX. Probably more over time. And that's just ones that I know about in this one county. Why? Because it would provide a practical solution to a very real problem - how to get modern messaging connectivity for the appliance-operator ham. Because their price-point was about the price of a dual-band mobile - very reasonable. And because, as I mentioned earlier, faster/higher frequency just isn't an option for most of those people due to line of sight problems. Michael N6MEF

Hmmm, I don't think so -- at least not in the strict sense used for microwave. A proper line of sight would certainly reduce both attenuation and multi-path. Both are a problem at microwave frequencies. Which is why n*GHz radios won't sell many units to the average ham at home. But UHF has the advantage of not being hampered so much by attenuation from trees and the like. That's why it's attractive for us, even if the bandwidth is lower. And, UHF multi-path isn't as much of a problem as for GHz, but still more of a problem than at VHF. So it will work will without clear line of sight, but not from all the places that VHF packet would work. FEC will be essential. As for new modulation schemes: I believe NWD was going to be using a chipset from a commercial data radio (I don't know the details). The "not reinventing the wheel" approach sounded good to us, because we pride ourselves in our uptime/availability for EmComm use. But one would also hope that the radio would be capable of software upgrades to modulation schemes as well. That would be attractive to those who are into experimentation. Bottom line: Many projects fail because they focus on speed or some other esoteric means to an end, but not on the end itself -- the application. And without an application, there are no users. And without lots of users, the idea will die. So we don't look at a potential 56k-100k UHF radio as much slower than microwave and narrower coverage than VHF packet. We look at it as way to carry what is probably the most ubiquitous application in the world today: e-mail. And, by the way, it happens to have MUCH, MUCH broader coverage than microwave (the ONLY possible coverage for many), AND be MUCH, MUCH faster and more feature rich than packet. Michael N6MEF

Regarding 56k+ on UHF it can be done, at east commercially. I worked for DataRadio which was owned by Bob Rouleau VE2PY; and Norm Pearl VE2BQS of the Montreal Packet Net originators of ham radio packet. When I worked there in 2000 we were implementing 56k on UHF using parallel decode technology that used 3 Z80 processors in the radio. I installed a system in MT and conducted drive testing in a police car at speeds up to 108mph (guaranteed to 80mph but you tell the guy with the gun to slow down). It worked with few dropped packets even in areas where multi path was a problem on their voice systems. I don't know what they had going on in the DSP and the parallel decode it was all kept very much from us in the Atlanta office, however it almost seemed to like the multi-path exceeding the coverage plots generated by the very expensive software predicted. The radios were manufactured in WI (they were dumb radios at this point with no firmware to speak of. The radios were then shipped to DataRadio Canada for DSP and firmware loading then shipped back to DataRadio in Atlanta for distribution to the specific customer. (not shure but I think there was some sort of tax advantage to this process or they must not have wanted the DSP process that was radio specific to go out to the US companies. We then built the base stations (Tait repeaters with 2 RX units and a DataRadio Base controller) and shipped them to the local installer. One of the engineers would show up for testing after the first 10 cars were installed as well as the base stations. If you see one of these radios for cheep on Ebay or at a ham fest it is likely 800mhz, but pick one up just for disection. They will be labeled Gemini PD, or PD+ I would love to look at the code for what all they were doing with Z80 processors. http://www.amateurradio.com/upcoming-37th-anniversary-of-packet-radio/ Lin N4YCI

Michael, Big money, but the history is very interesting. I am guessing the new stuff is even better, but in reality LTE is going to work much faster and better especially now that the channels have gone to 12.5khz. Lin On Wed, Sep 6, 2017 at 2:11 PM, Michael Fox - N6MEF &lt;n6mef(a)mefox.org&gt; wrote: -- Lin Holcomb Office: +1 404 806 5412 Mobile: +1 404 933 1595 Fax: +1 404 348 4250