Hi Rick You could get the Free RADIOAMATEUR Trial Test version [for 30 day trial] and do some experiments with that in the higher bands - this will allow you to experiment up to 8000 bits per second in wide bandwidth or up to 6666 bits per second in normal SSB bandwidth on HF
You should run a Sample rate test program like CheckSR etc at the sample rate of 48k and then enter these figures in the program under Options/Preferences/Hardware - good transfer speeds will still depend on BOTH ends having calibrated correctly If you do try the TRIAL software you will find that there are MANY other options available to you to use like Waterfall - Email Client - Beacon - Unconnected chat between like stations - compression - File transfer RESUME if file uncompleted at last session and other things Now to sum things up Amateurs have the Freeware version .498 to use at no cost for file transfer and local mail at a speed of up to 2666 bits per second If you want a permanent Mail-Client version of RFSM8000 it costs $60 US If you want to be a Mail Server Current price is $180 US [This is the only issue I have with the pricing - in order to encourage the use I believe the Server software should be available at no cost to a few SELECTED stations in various countries who would be interested in supplying the Server facilities for others to use - remember that this is an ongoing cost the them to supply these facilities to other amateurs] There are many other amateur software writers wanting $50 US for their software so I guess inflation has caught up in the requirement for $60 for this program - hihi I also realise that there are many other Amateur writers that supply their software for FREE and I applaud this - what would all of us retired amateurs do to keep our minds active if we didnt have all these things to do and toys to play with Yes there are groups here in VK testing RFSM8000 on VHF but I have no reports on hand regarding this at the moment Les VK2DSG From: Rick Sent: Sunday, January 27, 2008 2:16 AM To: digitalradio@yahoogroups.com Subject: Re: [digitalradio] Report on RFSM2400 vs. OFDM Hi Les, This was the first time I could get anyone to even try the mode as I have been attempting that for some time. From what I can tell, you need to be connected in order to do much with the mode to really do any kind of testing other than perhaps calling a "dummy" station. In regard to your questions: 1. I may have an older version, but I don't find a sound card offset in the Options. My sound card has been extremely accurate (Sound Blaster Live!) when tested with other programs and can be within a Hz or two. 2. The sampling rate is set to 48000. 3. My main interest is having very robust modes that work at the highest possible speed under the most difficult conditions. I have spent considerable time sifting through the materials found on the internet on STANAG modems (I will use the term STANAG as a short form of what is a large number of different modems) and from the published information, the throughput drops off rapidly when you go below zero dB S/N. The throughput last night did not really quite meet those expectations, but this may be due to other factors, such as insufficient computing power or the software modem not being able to match the multi thousand dollar STANAG modems. At least that seems reasonable to me, otherwise, why would governments spend the astronomical amounts of money for such modems? Having said that, my inside information from those who actually use these modems for government/military use, find that they don't work quite as impressively as the advertising might suggest. But at least we are getting a taste of what we can expect from this kind of technology. Perhaps others may have more information to compare the relative performance of the software modems of various types? Also, have you tried these modems on VHF? Here in the U.S. we can use them above 50 MHz, and I think we can mix and match modes there as well. I have not found anyone to test this with my mediocre 6 meter antenna, but I just realized that this may actual work dramatically faster than NBEMS. If Skip, KH6TY is reading this, perhaps he can comment. 73, Rick, KV9U
