Re: [Flexradio] SDR defined
Wikipedia has a definition and discussion of software defined radios. The page also has a link to a list of software-defined-radios, obviously incomplete as it does not include Flex. The link is at the bottom of the article in the section "See Also". It also has a link to a list of web-based software-defined receivers in the section "External Links". A Google search turns up more definitions of SDR. There seems to be a difference of opinion whether code stored in a ROM (fixed or reprogrammable) qualifies as software. The military JTRS (Joint Tactical Radio System) program is a long running program to produce a common radio platform (the hardware) to run all the military radio waveforms (the software). Their experience provides solid evidence that the software is not necessarily easier to create or to change than is the hardware. For what it's worth, JTRS is understood to be an SDR and the software is stored in ROM. As this discussion thread has highlighted, there are many ways to implement some of the functions of a radio in software. I happen to be quite fond of the way Flex Radio Systems does it. Thurman Irving, AA5KK -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Dave Gomberg Sent: Monday, December 12, 2011 12:55 PM To: flexradio@flex-radio.biz Subject: [Flexradio] SDR defined At 15:10 12/11/2011, Jim Jerzycke wrote: >We're discussing it because a lot of people don't have a clear >understanding of what a Software Defined Radio actually is. Well, when I wrote a talk about SDR I defined an SDR this way (talking about rcvr, but xmit is similar): A radio has five jobs: 1. Amplification (picowatts from the antenna to watts to the headphones or speakers) 2. Band selection (to permit adapting some later functions to a narrower frequency range) 3. Frequency reduction (from MHz to KHz) 4. Tuning (to reduce the region of focus from many KHz to a few Hz or KHz). 5. Demodulation (to recover the signal from its processed form (think FM for example)) A conventional radio accomplishes ALL these functions in hardware. Because of speed/bandwidth restrictions, ALL current radios do 1, 2, 3 in hardware or special purpose microchips. I said it was an SDR if it used software or upgradable firmware to accomplish any of 1-5. Notice that the FCC appears to believe that software is easier to upgrade than hardware. If you think about most MARS mods, this is clearly wrong, but the FCC gives diode-lifting a free ride because it is a hardware mod. And nowhere does the FCC consider data mods. If band frequency and mode limitations are governed by a table, then changing the table is NOT a software mod. H. And firmware mods are apparently considered hardware because they are implemented in a ROM, not code on a hard disk or floppy or CD. Suppose it is an EAPROM? This is clearly an area that needs rethinking by minds more technologically competent that those used so far. -- Dave Gomberg, San Francisco NE5EE Programming since 1959 All addresses, phones, etc. at http://www.wcf.com/ham/info.html - ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
Re: [Flexradio] Enhancement Requests
In my work, including systems engineering and process improvement, we were schooled to ask "Why" repeatedly to (as you phrased it) "cut through all confusion and lay bare the meat of the problem". It works! Try it on any problem you might have (except those involving the XYL - that leads to more problems). Bud Irving AA5KK -Original Message- From: flexradio-boun...@flex-radio.biz [mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Brian Lloyd Sent: Thursday, November 03, 2011 11:00 AM To: flexradio@flex-radio.biz Subject: Re: [Flexradio] Enhancement Requests On Thu, Nov 3, 2011 at 3:06 AM, David Painter wrote: > Not surprisingly the 640+ enhancement requests, going back to 2006, have > now been removed from the FRS site. > > I suppose it is easier to remove these 640+ requests than it is to provide > Flex customers with the functionality they have been saying, for years, > they want. > > Ah yes, enhancement requests. They are viewed by users as the panacea and by GOOD developers as an evil nightmare. Why? Because most enhancement requests are worse than useless. You see, we all like to solve problems. So when we have a problem, we solve it in our heads, and then issue a request for a solution rather than explain the problem we are trying to solve. As a result, the "feature request" rarely coordinates with the rest of the system to provide a uniform and cohesive system. I learned about this from a gentleman by the name of Steve Willens, the most brilliant programmer, engineer, AND CEO I ever worked with. In the early days of the commercial Internet, his dial-up access boxes were the overwhelming choice of the early Internet Service Providers. Why? Because they were simple and they worked ... and worked ... and worked. The software never broke. Even the beta test software he put out was more functional and reliable than the 2nd and 3rd generation release code by any of his competitors. Later his company acquired mine and I ended up running my company as a division within his. As a result I had to meet with him on a regular basis. Until then I thought I was one of the best but quickly learned that, next to him, I was a piker. Steve, with a simple question, could cut through all confusion and lay bare the meat of the problem. He was able to do that because he was always thinking about the system, not the feature. It was interesting because, before he bought my company, I was one of his customers. For years I had to opportunity to work with him on adding necessary functionality to remote access servers. (To this day *EVERYONE*in the world uses his system for remote access authentication, authorization, and accounting on the Internet.) The key question he would always ask was, "But what are you trying to do?" He never wanted to hear about how we wanted to solve a problem, he wanted to hear about the problem itself. As a result he would often combine various problem spaces and craft a much simpler system that would address several problems at once. The result may not end up looking like what the customer was asking for but it always solved the problem and usually did so simply and elegantly. The code always ended up being simpler and better compartmentalized so we encountered fewer bugs. As a result his devices were the only ones I could place in a remote, rural location where I couldn't get my finger on the reset button, without suffering from nightmares. So, I applaud the demise of the feature request. What Flex really needs are operating scenarios, not feature requests. Flex needs to ask, "What are you trying to do," not, "What do you want us to add?" The only way feature requests are useful as a kind of hieroglyphic that implies a problem the user wants to solve but then they have to guess at the actual nature of the problem. Unfortunately THAT requires that the person evaluating the feature request to be some kind of forensic expert, divining the characteristics of the problem "creature" from the request "turds" left lying around. And then, only after they have a real picture of the problem they are trying to solve, can Flex craft a real system. So, I don't see this as a problem. I see this as likely being a HUGE step in the right direction. Think about it. -- Brian Lloyd, WB6RQN/J79BPL 3191 Western Dr. Cameron Park, CA 95682 br...@lloyd.com +1.767.617.1365 (Dominica) +1.916.877.5067 (USA) ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/ ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/
[Flexradio] Fail to transmit from JT65
Has anybody seen this? I have been working JT6 for the last few weeks and have close to 100 contacts. It has been working ok with PowerSDR 2.0.22 until yesterday. Then I upgraded to PowerSDR 2.1.5. I am able to receive via PowerSDR 2.1.5 but cannot transmit. Most received signals have DT well below 1.0. The problem is that JT65-HF does not key the transmit function in PowerSDR 2.1.5, it continues to function in the receive mode. As a sanity check I tried PowerSDR 2.0.22 again. It worked just fine in both receive and transmit modes - for about one more day. Now it also fails to key the PowerSDR transmitter. I have checked and triple-checked my CAT settings and they are the same as in PowerSDR 2.0.22 when it was still working. I have reinstalled JT65-HF and PowerSDR 2.0.22 to no effect. I restored Windows to an earlier restore point to no effect. My system did crash with the blue screen of death and mentioned "bad_pool_caller". A search at microsoft.com indicates that this is a symptom of corrupted driver files. I have not had this crash since restoring Windows and reloading PowerSDR and JT65-HF. I have run my virus checker and it founds several cookies, nothing else. My system: Windows 7 64 bit PowerSDR 2.0.22 (for now, I intend to go to 2.1.5 when I get this fixed) VAC 4.9 VSP Manager 1.0.1.017 JT65-HF NTP 4.2.4p8 Flex 5000A PowerSDR 2.1.5 is currently uninstalled. Thanks in advance for your thoughts. Bud Irving AA5KK ___ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flexradio.com/ Homepage: http://www.flexradio.com/
