Re: [digitalradio] Path Simulator Test - PSK FEC31
If the SNR is negative, how is it that you can copy any signal? 73, Mark N5RFX At 02:36 AM 8/21/2008, Tony wrote: __ Sensitivity Test - Direct Path (no ionospheric disturbance) Minimum SNR for error-free copy Contestia 500/32-15db DominoEX-4 ..-15db F
Re: [digitalradio] Path Simulator Test - PSK FEC31
At 04:31 PM 8/21/2008, Tony wrote: The path simulator adds Gaussian white noise to the input signal to simulate a signal-to-noise ratio through a 3KHz band pass filter. If the SNR is less than 0, it's below the noise level. Tony, thanks the bandwidth is 3K for all modes that is what was throwing me. I was thinking S/N = Eb/No. I see my mistake now. 73, Mark N5RFX
Re: [digitalradio] Re : Mix W software.
At 04:19 PM 6/27/2008, Mel wrote: Regarding the previous post's mention of re-calibrating the sound card, how is this done ? There is a program in C:\Program Files\MixW called CheckSR.exe . This program will help you calibrate your sound card. First run your test with a sample rate of 11025 Let it run for a while and if you get big numbers in the difference ppm boxes, then your soundcard needs to be calibrated. Run it with a sample rate of 12000 and see if the difference ppm numbers are two digit. If 12000 didn't make a big difference, then take the TX and RX difference ppm numbers and enter those in MixW Configure Sound Device settings clock adjustment ppm for TX and RX respectively. If 12000 looks good change the sample rate in MixW Configure Sound Device settings to 12000 and enter the PPM numbers from CheckSR.exe . Good luck and 73, Mark N5RFX
Re: [digitalradio] Re:Update: Digital Modes in 2008
At 12:53 PM 6/5/2008, Rick W. wrote: Paul Rinaldo, ARRL CTO, has gone on record as claiming Hell modes to be J2D when being transmitted from an SSB transmitter as most of us do. Looking at the ITU Emission Classifications, it seems to me that J2C would be more appropriate. You are correct. Paul was just rationalizing at the time because emissions with a C as the third symbol were not authorized in the RTTY/Data subbands on HF. It was easier to proclaim Hell as J2D than it was to petition the FCC to allow emissions with a C as the third symbol to be transmitted in the RTTY/Data subbands on HF. Paul was probably correct in his method, as it appears the FCC is not concerned about emissions designators anymore. It would be nice if they would make the rules match their feelings. 73, Mark N5RFX
Re: [digitalradio] Signals on 3584 + audio
At 08:49 AM 5/14/2008, kh6ty wrote: The problem with MFSK16, as you found, is the mistuning tolerance. For messaging, when there is a fast series of ARQ exchanges, if one station has uncompensated offset between RX and TX (NBEMS must work with untrained and inexperienced operators to be successful for emcomm), and if the offset exceeds 4 Hz, which is not so unusual, eventually it will not be possible to decode MFSK16, and therefore the ARQ requests or confirmations may be missed. Skip, One thing I have found is that when the sound card can be configured for a 12000 Hz sampling rate, the offsets are not present in most sound cards. It seems that when 11025 is used that the offsets are noticeable in many sound cards. I am not sure how an 8000 Hz sampling rate performs, but just thought I would mention this observation. 73, Mark N5RFX
Re: [digitalradio] FCC Denies Digital Stone Age Petition RM-11392
At 08:47 PM 5/7/2008, expeditionradio wrote: In FCC's official consideration statements, FCC specifically supports no finite limit of bandwidth for digital data emissions for the amateur radio service. FCC instead prefers to rely upon existing rules, and to encourage amateur radio operators to advance the radio art. FCC said that imposition of such limits might impede experimentation and technological innovation. I think this is the most important part of the FCC statements in denying my petition. I am glad to see the FCC comment on enumerating bandwidths. I am disappointed that the FCC did not elaborate on the purpose of Section 97.307(f) which limits specified RTTY or data emissions to a symbol rate not to exceed 300 bauds (in the 80 to 12 meter bands) or 1200 bauds (in the 10 meter band); or for frequency-shift keying (FSK), to a maximum frequency shift of 1 kilohertz between mark and space. Why is that there? The FCC has spoken and the status quo prevails. 73, Mark N5RFX
Re: [digitalradio] RTTY question
At 08:36 PM 3/28/2008, you wrote: Why do I find so so many RTTY signals up side down on the ham bands. I think it is because many of the sound card programs give you mark high and space low when the rig is using USB. A newbie asks which sideband to use and someone invariably says LSB. USB/LSB depends on which software package that you use and its defaults. I use MixW and to get mark high space low you using the defaults with AFSK, the rig should be set to USB. I don't think many inexperienced operators actually check to see what RF frequencies they are actually transmitting. 73, Mark N5RFX
Re: [digitalradio] FCC Petition to Re-Establish Narrowbnad RTTY/Data Subband Comment Period Open
At 11:28 AM 12/28/2007, you wrote: Hi Mark, How would this kill various digital modes with a bandwidth of 1500 hertz or less? I operate Oliva mostly at 500 hertz wide and sometimes and 1000 hertz wide. 73, tom n4zpt If a mode's bandwidth is 1500 Hz or less, then there would be no change in authorization. It is as simple as that. 73, Mark N5RFX
[digitalradio] Fwd: Your excellent petition
Forwarded with the permission of G3PLX Subject: Your excellent petition Date: Wed, 26 Dec 2007 20:37:30 - X-Mailer: Microsoft Outlook Express 6.00.2900.3138 Mark: I hope I have the right email address This is just a note to offer my congratulations and express my admiration for the work you have put in to your petition to FCC, which I have only just seen as a result of various people drawing my attention to it in the last few days. You may know that I was the only non-U.S. citizen to be invited to serve on the ARRL Digital Communications Committee when it was considering what should be the response of the ARRL to the moves in Europe towards separation by emission width, which are now built into the IARU region 1 bandplan. It was me that first proposed the change from segregation by mode to segregation by emission width within IARU region 1. The ARRL committee subsequently reported back to the ARRL board, and you will be well aware of the result. I resigned from that committee before it reported, because it was clear to me that the committee was dominated by a small group whose sole aim was to gain additional spectrum for voice-band unattended digital traffic-handling. They were simply hijacking the separation by emission width debate to further this aim. The result was a disaster, and it's down to people like yourself to sort out the mess! While I was on the committee, however, I tabled arguments almost exactly identical to those you have outlined in your petition, drawing attention to the inappropriate use of ARQ techniques (not just Pactor 3) in the amateur service. The use of ARQ in a congested band is counter-productive, since in the face of co-channel interference (which results from congestion), it INCREASES the amount of time-bandwidth it uses, thus making the congestion worse. I went on to generalise this discussion. To be able to survive congestion in an unregulated band, there must be a mechanism that causes individual transmitting stations to REDUCE their output (in time-bandwidth terms) when faced with undesirable congestion. The AX25 protocol, much maligned for HF use, did achieve this. I will come back to this, but it's also self-evident that all traditional one-to-one amateur operation has this desirable feedback mechanism - an operator faced with QRM due to congestion will shorten his transmissions or close down, thus reducing the congestion, or at least he will do so if he doesn't have any important traffic to pass. This leads to an important conclusion about amateur radio in an unregulated environment where the level of activity is congestion-limited. It will ONLY be stable and self-limiting if there are enough people on the air who are just there for fun, and who will QRT if/when it stops being fun. If we ever got to the situation where a significant fraction of the activity was by people who needed to be on the air for a purpose, then there will be an increasing tendency for congested bands to exhibit 'grid-lock' behaviour. We don't have a big problem over here in Europe. For a start, the use of amateur radio for third-party traffic is illegal everywhere except the USA, so virtually all amateur activity is of the recreastional (fun) type. But I can see it becoming a real problem in USA, and especially if ARQ modes like Pactor become a dominant fraction of the total. When we were discussing emission width segregation in Europe, it became clear that although disparity in emission widths was the most significant source of conflict between operators of different modes, it wasn't the only source of conflict. We identified unattended operation as another major source. With this in mind we created, within the bandplan, segments for this type of operation. This is working well. There is no longer a significant level of complaint by one-to-one operators from unattended systems. I said I would come back to AX25. The fact that AX25 'backed off' in the face of errors (which could be due to congestion) meant that multiple AX25 links could share a channel in a stable way. Pactor has no such characteristic. Co-channel QRM between two Pactor links results in neither link passing any traffic until one link aborts. The logistic consequence of this is that Winlink sysops will always choose to operate on a channel on which they can be sure no other Pactor link will take place. They will always prefer to be subjected to random QRM from another service than to be subjected to QRM from another Pactor link. This unfortunate characteristic has meant that the interference from Pactor to other services is maximised rather than minimised, and it also means that the Winlink organisers complain bitterly that there is insufficient space within the designated automatic sub-bands. The total volume of traffic handled by these unattended stations could easily be passed within the automatic sub-band limits, given a mechanism by which
Re: [digitalradio] Fwd: Your excellent petition
Hey, I thought I was the only guy who labels his socks by day. :-) This petition, if adopted, will be a huge step towards advancement of the digital modes on the amateur bands, and a clean-up of non-amateur modes and practices that threaten our bands. Roger, I had my wife take a look at that comment about the socks and she about died laughing. I should post a picture of my shack and that would explain her reaction. Thank-you for your comments. Peter is a great guy and a wonderful philosopher. 73, Mark N5RFX
[digitalradio] FCC Petition to Re-Establish Narrowbnad RTTY/Data Subband Comment Period Open
The FCC has released http://fjallfoss.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6519820340 Public Notice report 2828-Correction establishing a new comment period for http://fjallfoss.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6519008574 RM-11392. RM11392 asks the FCC to re-establish the narrowband nature of the RTTY/Data subbands in the 80 through 10-meter bands. Emissions have crept into the narrowband RTTY/Data subbands in the 80 through 10-meter bands that are not appropriate for the RTTY/Data subbands. Stations under automatic control have taken advantage of loopholes created by terminology in the commission's rules that is not applicable to new operating modes. Please read RM-11392 . and make comments to the FCC. Here are the steps. 1. Read http://fjallfoss.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6519008574 RM-11392 part 1 and http://fjallfoss.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6519008575 RM-11392 part 2. 2. Look at the other comments filed. To do this go to http://fjallfoss.fcc.gov/prod/ecfs/comsrch_v2.cgi FCC EFCS Search for Filed Commentsand enter RM-11392 in box 1 labeled proceeding. 3. Enter your own comments by going to http://fjallfoss.fcc.gov/prod/ecfs/upload_v2.cgi FCC Electronic Comment File Submission page. 73, Mark N5RFX
Re: [digitalradio] Re: New Digital Voice Mode FDMDV
At 06:27 AM 12/11/2007, cesco12342000 wrote: Here is my XYL after encoding with MELP and FDMDV Are you trying to discredit the program by posting worst-case examples ? No. Are you trying to embellish the program by only posting best-case examples? 73, Mark N5RFX
Re: [digitalradio] Re: New Digital Voice Mode FDMDV
Can you measure the crest factor in function of ALC button ? Yes the crest factor fell to 11 dB. 73, Mark N5RFX
Re: [digitalradio] Re: New Digital Voice Mode FDMDV
My own audio sounds quite similar, but i have heard some stations with excellent audio on this codec. I think we should move the mic further away and use a pop and hiss filter, or move the mic sideways. Would be intresting to have original and coded audio to compare. Here is my XYL after encoding with MELP and FDMDV http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/claudia_encoded.mp3 Here is what she sounds like normally http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/claudia.mp3 73, Mark N5RFX
Re: [digitalradio] New Digital Voice Mode FDMDV
Personally I feel the words high quality may overstate it. Traditionally there has been a trade-off between bandwidth and quality, the less bandwidth the worse the quality. But it's free and costs nothing to try so I'm downloading my copy and if it comes anywhere close to the quality of a 2.4 kHz SSB transmission then I'll be more than happy I have made some tests with FDMDV. Spectrum analyzer display showing the 1.143 kHz occupied bandwidth http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/vdmdv.jpg Spectrum analyzer display showing 3 of the 15 carriers. The markers (aquamarine and purple) are spaced 75 Hz apart http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/fdmdv1.jpg Base band audio http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/baseband.mp3 Audio http://home.roadrunner.com/~mdmiller7/images/dv/fdmdv/audio.mp3 Not too bad for such a narrow bandwidth! 73, Mark N5RFX
Re: [digitalradio] Re: Very confused
At 05:29 AM 7/1/2007, Roger J. Buffington wrote: Not 28070? Nope 28.120. There is a PropNET PSK31 beacon on 28.131 . Back during the last peak of the sunspot cycle 28.131 was a hotbed of MT63 activity. 73, Mark N5RFX
Re: [digitalradio] Anyone using Xastir ?
At 09:14 PM 6/30/2007, Andrew O'Brien wrote: Anyone hear running Xastir ? Andy K3UK Yes version 1.9.1. N5RFX-8 is an IGATE connected to a Tracker 2 (N5RFX-6) in Kiss Mode. I have been thinking about switching to DIGI_NED so that I can bring in a 9600 baud 440 MHz APRS channel. 73, Mark N5RFX
[digitalradio] Field Day NTS traffic
I will be operating Field Day as N5RFX between Comanche and Rising Star Texas. At the top of the hour I will call for NTS traffic on 14.109.5 (dial frequency). You can send your field day section manager report to this field day station. I will calling for traffic in MT63/MFSK and Olivia (16 tones 1k bandwidth). Other stations should do this too, so that section manager NTS traffic can be serviced. I would prefer to handle traffic with a telephone number so that I can immediately deliver the message, but mailing addresses will be serviced after field day is over. At 0200 UTC I will switch to 7.090 (USB Dial frequency) 73, Mark N5RFX
[digitalradio] Field Day NTS traffic
I will be operating Field Day as N5RFX between Comanche and Rising Star Texas. At the top of the hour I will call for NTS traffic on 14.109.5 (dial frequency). You can send your field day section manager report to this field day station. I will calling for traffic in MT63/MFSK and Olivia (16 tones 1k bandwidth). Other stations should do this too, so that section manager NTS traffic can be serviced. I would prefer to handle traffic with a telephone number so that I can immediately deliver the message, but mailing addresses will be serviced after field day is over. At 0200 UTC I will switch to 7.090 (USB Dial frequency) 73, Mark N5RFX
Re: [digitalradio] Re: Tearing Down USA's Data Wall (300 symbols/second)
440 MHz has had a authorized bandwidth of 100 kHz for nearly 20 years. The repeaters and other operations there seem to work just fine. Just because the authorized bandwidth is 100 KHz doesn't mean that the whole band will be filled with 100 Khz signals. 73, Mark N5RFX WALT ... THINK THINK ... 100 khz wide signals are going to KILL any band you put them on and do you think anyone will look for OTHERS before fireing up a digital radio .. GEESE go on 75 and lissen to SSB they can't even handle THAT mode ..
Re: [digitalradio] Re: Tearing Down USA's Data Wall (300 symbols/second)
Bruce, I will work it out when 6 is OPEN world wide and not interfere with repeaters on 2 meters because I will continue to follow the clause that says no amateur operator shall willfully or maliciously interfere with or cause interference to any radio communication or signal . How does changing the authorized bandwidth affect the prohibition on interference? 73, Mark N5RFX 440 ALSO has NO SKIP and 8 TIMES the space NOW how are you going to work it out when 6 is OPEN world wide ? ANYONE with a half a brain knows 6 is not the place for this .. also how are you not going to interfere with repeaters on 2 meters they cover 3 out of 4 mhz of that band ?
Re: [digitalradio] Re: Tearing Down USA's Data Wall (300 symbols/second)
The ARRL has no clue . and do not care . I respect your opinion. When open 6 meters is packed solid from 50.105 to 50.5 with ssb there are AM users on 50.400 and PSK-31 between 50.5 and 50.7 RIGHT NOW the band is closed but it will not be in 2 to 3 years the only open spot is between 50.7 and 51.5 above that are simplex nets and repeaters . What you are describing is a result of a bandplan, not regulation. Changing the authorized bandwidth does not change the bandplan or the requirement that we don't interfere with each other. Perhaps we should limit 6 meters to PSK and CW type bandwidths? On 2 meters here in tampabay 144.200 - 144.300 is week signal work with nets on 144.210, 144.250 common here in fl and 144.300 - 144.400 APRS users used in this state. EXCEPT for 146.500 - 146.600 and 147.500 - 147.600 evenything above 146.000 is used be repeaters. simplex nets and users are common on 146.500 ( or 146.490 ) 146.520,146.550 and 146.580 and again on 147.20 55 and 58 Again, this is the result of a bandplan, not regulation. How would increasing the authorized bandwidth change this bandplan or the requirement that we don't interfere with each other? now where are you going to put 500 100 khz wide signals? EXCEPT on 220 or 440 and only because 220 has no one on it and 440 is so big? Increasing the the authorized bandwidth does not require placing 500 100 kHz wide signals on 6 and 2 meters. I think that what you are concerned about is the capacity of a band will be decreased by increasing the authorized bandwidth. Since the FCC does not limit the number of licensees in the ARS I don't see why they will be concerned with capacity. Increasing the authorized bandwidth does not require emissions to use the entire authorized bandwidth. Its like I tell my co-workers when we are traveling: just because the room is a smoking room, does not mean you have to smoke in it. I do understand your concerns Bruce. I don't see the need to increase the authorized bandwidth on 6 and 2 meters and would avoid it for political and public relations reasons. 73, Mark N5RFX
Re: [digitalradio] Re: Tearing Down USA's Data Wall (300 symbols/second)
I think this is true in the part 90 world, but not in part 97. There really is no FCC mandate with respect to the ARS for spectral efficiency. 73, Mark N5RFX In a time period shorter than most of us realize, most of the VHF and UHF bands will be all digital. The FCC is moving all other users in that direction anyway. No more WFM, just NFM, etc. They want greater spectral efficiency. Look at D-Star digital voice! It is only 6 kHz bandwidth.
Re: [digitalradio] Re: Tearing Down USA's Data Wall (300 symbols/second)
Bruce, We have had PSK and RTTY and APRS users for DECADES and because they take up similar space they do not cause a problem AND they have place themselves AWAY from most other users . This is what bandplanning, gentlemen's agreements, and cooperation give us. Your example shows how a 32 Hz mode is living amongst 3 kHz and 16 KHz modes. however you know unlike the 5 watt comments What we see on 6 is the HIGH power boys crawl out of the woodwork at the slightest band opening NOW take 500 100 kHz wide 1KW signals mix them and add in how intense skip at 50 MHz can be and it will sound like Cb ... What if we said: take 2500 20 kHz wide 1KW signals mix them and add in how intense skip at 50 MHz can be and it will sound like Cb? Last year i sent out over 300 QSL cards on 6 SSB alone also a smaller number on 52.525 FM and a handful on 50.4 AM I have PSK-31 but at this time it is not working correctly but one opening MANY psk-31 stations were on 6 along with the CW/SSB/AM and FM guys. I have worked 6 on PSK31. It is quite fun. IF the ARRL had restricted it to ABOVE 50.5 and BELOW 51.5 Most of us could live with it because that part of the band is VERY lightly used and far enough away from weak signal users that it would not be likely to cause problems . This can be done with bandplanning. We cannot assume that the folks who would choose to run 100kHz signals are unlawful or uncooperative types. This is NOT a digital must be stopped thing but a digital needs to be able to live with all the other modes . Agreed, and we must have faith in our fellow ham. I must remind you only the good die young . And I'm not known for being good . Excellent! 73, Mark N5RFX
Re: [digitalradio] Re: Report of the ARRL Ad Hoc HF Digital Committee Dissenting
The root cause of the complaints can be traced to the way that Pactor III was introduced to the amateur bands. Most hams today consider the appropriate bandwidth of a signal in the RTTY/Data subbands to be 500 Hz. Wider bandwidth modes have been tolerated, but they typically are limited to one or two frequencies. MT63 is a good example. You did not find MT63 typically on more than 1 frequency per band, and you found that operators limited their bandwidth to 1000 Hz with the occasional foray to 2000 Hz. On 40 and 80 meters they limited their bandwidth to 500 Hz. m. The introduction of Pactor III into the amateur radio bands flew in the face of such tradition. It was used by a small number of users who unnecessarily spread out over the bands, and quite frankly pissed people off. Now the impression is that Pactor III users are spectrum grabbers. The main objection to the ARRL regulation by bandwidth petition was the fear that Pactor III would proliferate in what is now the phone bands. If PACTOR III had been deployed with constraint, I don't think you would find the angst that we have now against the mode. Even before PACTOR III, there was a bias against automatically controlled digital stations. I can remember this in the early 90s when APLINK was around. Many hams feel that QSO's should be between two humans, not a human and a machine. This bias against unattended operation was already present when Pactor III was introduced. Had the bandwidth used, been commensurate with the number is users I don't think PACTOR would have the poor reputation that it does today. Its really not a technical issue as much as it is a public relations issue. Why is there no SCS presence at Dayton and why is there not a Winlink or PACTOR forum at Dayton? The answer can be found in the way that unattended stations using Pactor were deployed. I am not sure what it will take to correct this, but the damage has been done. In the ARRL's defense, when they looked at WinLink at their Board Meeting, there was nothing else on the technology front that could do what WinLink was doing. And until PSKMail came out, there WAS NOTHING to equal WinLink.
Re: [digitalradio] Re: Pactor versus Olivia
Rick, This is certainly lost on the Pactor III group. 73, Mark N5RFX having many small bandwidth users means more throughput for more users than one large bandwidth user at a time.
Re: [digitalradio] One last project to complete - FSK keying
Dave, You can use a sound card program like MTTY or MixW which lets you set up the com port on a PC for FSK to your rig. Here is one way http://www.aa5au.com/rttyinterface.html The best way in my opinion is to use an opto-isolator something like this http://www.qsl.net/k0bx/soundcard.htm You know you can use your narrow filter in USB and LSB. When I had my 746 non-pro, I just told the radio that the narrow filter was actually a SSB filter. 73, Mark N5RFX I know the 746 keys FSK from the ACC socket on the rear, but is there any way to key this mode without having a TNC?
RE: [digitalradio] Re: New ARRL Petition
Maybe they should have tried this approach instead of petitioning the FCC. 73, Mark N5RFX At 09:24 AM 12/15/2006, you wrote: Only from the League's lawyer, silly. That's as good as it gets. Anyway, does anyone really want a response directly from the FCC, for Cat's sake?! Not I, dear sir. Especially after their recent Uni-Bus or whatever that crash was (HI).
RE: [digitalradio] USA: No Advanced Digital HF Data Comms for HamsRe: RFSM2400
Walt, I think there is no doubt that this is true. The question I have been struggling with is how much is enough/too much. I guess what I am looking for is a curve showing bandwidth vs. throughput for parallel tone modems, or maybe more precisely where is the point of diminishing returns? I am sure there are many factors that would affect the curves. I know from experience that MT63 is a great mode when making very long and many hop contacts. I have watched the fading move across the waterfall, and my text be 100% correct. I am sure that this is because of the redundancy of the code spread out over many frequencies. MFSK16 sometimes performs better under certain conditions with a quarter of the bandwidth. What my question boils down to is generally, what is the accepted maximum bandwidth of any signal in the Amateur HF bands, given the finite spectrum and many interests? 73, Mark N5RFX Research done by independent research labatories and universities confirm that the best bet to increase throughput and robustness on HF channel modems is to use parallel tone modems.
Re: [digitalradio] What constitutes a fax?
Rick, I have been working on such a plan. This plan keeps things organized the way they are now, but adds the multimedia playground 25kHz below the top of each band. Let me go through a summary, then you can look at the chart, and comment. 160 meters, no change from what it is now. 80 meters 3.5 to 3.6 MHz is all max 500Hz necessary bandwidth 40 meters 7.000-7.100 MHz 500 Hz, 7.100-7.125 MHz 2.8 kHz, 7.125 to 7.150 multimedia playground. The reason for this is because the automatic subband today begins at 7.100 and goes to 7.105, This would remain automatic control area, but the remainder from 7.105 to 7.125 would be for wider digital modes. 30 meters 10.10-10.14 MHz 500 Hz, 10.140-10.150 MHz 2.8 kHz. No multimedia playground on the WARC bands. 20 meters 14.00-14.100 MHz 500 Hz, 14.100-14.125 MHz 2.8 kHz, 14.125-14.15 MHz multimedia playground. The automatic subband at 14.0950-14.0995 MHz would be eliminated and the remaining one would be remain at 14.1005-14.112 MHz which closely matches Region 1. 17 meters 18.068-18.105 MHz 500 Hz 18.105-18.110 MHz 2.8 kHz, No multimedia playground on the WARC bands. 15 meters 21.0-21.090 MHz 500 Hz, while this may seem unfair, this is where the auto subband begins now. 21.090-21.100 2.8 kHz, the auto subband is 21.090-21.100 today, 21.100-21.2 multi media playground, a large chunk, maybe too big? 12 meters 24.89-24.925 MHz 500 Hz, 24.925-24.93 2.8 kHz. No multimedia playground on the WARC bands. 10 meters 28.0-28.120 MHz 500 Hz, 28.120-28.275 2.8 kHz. 28.275-28.3 multimedia playground. CW is still authorized everywhere. I don't want this thing to be too complicated, and really feel that only 2 bandwidths should be enumerated: a narrowband and wideband. I think this one is the most fair, as it mirrors what we have today, and provides some real protection to narrow band modes by enumerating a 500 Hz maximum bandwidth, which is not there today. but is implied. The chart is at http://home.comcast.net/~mdmiller7/arrl_alt/fcc_pet_digital_6_apendix_a.htm . I have a narrative written, but it needs to be modified to fit this chart. 73, Mark N5RFX Perhaps we should be carving out a frequency for playing with this digital stuff in the HF bands?
[digitalradio] ERRATUM
ERRATUM Released: November 27, 2006 By the Chief, Mobility Division, Wireless Telecommunications Bureau: 1 Federal Communications Commission DA 06- 2379 2 1. On October 10, 2006, the Commission released a Report and Order (FCC 06- 149) in the above- captioned proceeding. 1 This Erratum corrects the Report and Order by revising Section 97.3( c)( 2), as set forth in the Appendix thereto, to clarify the rule in accord with the pertinent discussion in the text of the Report and Order. 2 Specifically, this Erratum corrects the initial rule amendment in the Appendix of the Report and Order to read as follows: 1. Section 97.3 is amended by revising paragraph (c)( 2) to read as follows: § 97.3 Definitions. * * * (c) *** (2) Data. Telemetry, telecommand and computer communications emissions having (i) designators with A, C, D, F, G, H, J or R as the first symbol, 1 as the second symbol, and D as the third symbol; (ii) emission J2D; and (iii) emissions A1C, F1C, F2C, J2C, and J3C having an occupied bandwidth of 500 Hz or less when transmitted on an amateur service frequency below 30 MHz. Only a digital code of a type specifically authorized in this part may be transmitted. * * * * * 2. This action is taken under delegated authority pursuant to Section 0.331 of the Commissions Rules. 3 FEDERAL COMMUNICATIONS COMMISSION Roger Noel Chief, Mobility Division Wireless Telecommunications Bureau 1 Amendment of Part 97 of the Commissions Rules Governing the Amateur Radio Services, Report and Order, WT Docket No. 04- 140, 21 FCC Rcd 11643 (2006) (Report and Order). 2 See Report and Order, 21 FCC Rcd at 11653 ¶ 19 (stating, we will revise our rules to clarify that the 500 Hz limitation applies only to the emission types we are adding to the definition of data when transmitted on amateur service frequencies below 30 MHz. By amending the rule in this manner, the 500 bandwidth limitation will not apply to other data emission types or amateur service bands in which a higher symbol rate or bandwidth currently is permitted). 3 See 47 C. F. R. § 0.331.
Re: [digitalradio] What constitutes a fax?
I think you are correct. Text emissions have some sort of code which indicates the character to be transmitted. Such codes are Morse, Baudot, ASCII, and Varicode to name a few. Digital facsimile is pixilated and the pixel's intensity is represented numerically as in bitmap images. Pixels are simple black or white with simple images modes like Hellscrieber. Analog facsimile is most commonly a tone frequency which represents the intensity of a line drawn horizontally with respect to the image. Data when it is not telemetry or telecommand is anything else that is not text or image. 73, Mark N5RFX Since it can be transmitted in either analog or digital form with almost any kind of modulation and there are no encoding restrictions, a fax seems to be any printable document -- even if it isn't printed immediately.
Re: [digitalradio] Re: FCC Rules: Pactor-3 is OK on HF, and Pactor-1 is OK for Image.
I disagree. You can send images as long as the bandwidth is 500 Hz or less. That is what J2C is all about. A transmission can have more than one emissions designator as you have pointed out. You may start by sending J2B, then during the course of the QSO switch to J2C without ever changing the modulation type. With the image mode that is used with MFSK16 as employed by MixW, the emission there starts out as J2B, then switches to J3C, then back to J2B. But keep in mind that the new rules don't allow transmission of an image in the data subbands using Olivia or MT63 (any bandwidth). You have to QSY to the phone band if you want to use Olivia or MT63 for sending images. Bonnie KQ6XA
Re: [digitalradio] Re: FCC Rules: Pactor-3 is OK on HF, and Pactor-1 is OK for Image.
Roger, I will let Bonnie respond, but let me add my 2 cents. Paragraphs 15 through 19 address the rule changes which allow image emissions. Paragraph 19 has most of us confused because while it says we will revise our rules to clarify that the 500 Hz limitation applies only to the emission types we are adding to the definition of data; J2D was already in the definition of data before this revision. They also say the 500 bandwidth limitation will not apply to other data emission types or amateur service bands in which a higher symbol rate or bandwidth currently is permitted. There is a footnote to that sentence that references 97.305(c), 97.307(f)(3)-(8), (13). This would indicate that the intention of the revision to the definition is to add image emissions that have a maximum occupied bandwidth of 500 Hz. I am not sure why J2D was moved into the less than 500Hz area. I would only be guessing if I gave my hypothesis. 73, Mark N5RFX Actually, it is mostly Greek to me. I admit it. Are you saying that the above quote, beginning with the numeral 19 came out **after** the ARRL interpreted the regs as prohibiting Pactor 3? Or are you simply disagreeing with ARRL on the interpretation of the FCC regs? And how does this affect Olivia and MT-63? Since these modes were presumably included in the original definition of Data are they unaffected as well--i.e. 1Khz Olivia and MT-63 would be permitted below 30 Mhz? de Roger W6VZV
Re: [digitalradio] Re: FCC Rules: Pactor-3 is OK on HF, and Pactor-1 is OK for Image.
Jim, Yes, MT3 at 500Hz bandwidth may have an occupied bandwidth greater than 500 Hz. My spectrum analyzer has a hard time with bandwidths less than 500 Hz. I used to not have that problem with it, but I have changed something. I will have to check. I went through the resolution bandwidth and video bandwidth, but that did not help. The problem is that when I measure the occupied 26 db down, the bandwidth of a single tone it is 384 Hz. That used to not be the case. Maybe my delta 44 sound card is not as clean as I would have hoped. 73, Mark N5RFX At 11:56 AM 11/19/2006, you wrote: Bonnie, Why can't you use bandwidths of 500 or less in Olivia or MT63 to send images in the narrow subbands? My copy of gMFSK allows setting parameters of both protocols to values that should meet the requirements of the new FCC rules. I recognize MT63 may not have an occupied bandwidth of 500 Hz at its lowest setting, but I haven't researched that totally. Jim WA0LYK
Re: [digitalradio] 1000 Hz Olivia under USA new rules ?
Joe, I think your interpretation is correct, but there is much misinformation about this, mainly from http://www.arrl.org/news/stories/2006/11/15/100/?nc=1 . 73, Mark N5RFX My interpretation, which is as good as any at this point, is that telegraphy is plain text to be read and interpreted by a human operator on the spot, whereas data is information (including plain text) which was or is intended to be stored as a file or interpreted by a computer. Thus: Keyboard-to-keyboard QSO: Telegraphy (J2B) Automated exchange of QSO information: Data (J2D) MultiPSK's Reed-Solomon mode ID feature: Data (J2D) Loading and sending a text file: Data (J2D) Manually delivering/forwarding NTS traffic: Telegraphy (J2B) Automatically forwarding NTS traffic: Data (J2D) Forwarding mail: Data (J2D) Reading mail: Data (J2D) (it was stored in a file on the BBS) Sending a PDF/ODF/etc: Data (J2D) Sending a JPG/PNG/etc: Image/Fax (J2C) Sending a MNG/animated GIF/etc: Television (J2F) So, if you're simply having a keyboard-to-keyboard QSO, a 1 or 2 kHz-wide mode is legal.
Re: [digitalradio] Part of the problem
Yes you are correct about regulation by emission designators. The question really is when is the third symbol of the emissions designator a D? 97.3(c)(2) says that data is Telemetry, telecommand and computer communications. The third symbol of an emissions designator identifies the content of the emission. When the content is Telemetry, telecommand and computer communications and the signals are a single channel containing quantized or digital information with the use of a modulating sub-carrier and that sub carrier is modulating main carrier by the use of single-sideband, suppressed carrier then you must limit your occupied bandwidth to 500 Hz or less. On the other hand if the content is Telemetry, telecommand and computer communications and the signals are a single channel containing quantized or digital information without the use of a modulating sub-carrier, and the carrier is frequecy modulated then you do not have to limit your occupied bandwidth to 500 Hz or less. If the third symbol of the emissions designator is a B, then you don't have to limit your occupied bandwidth to 500 Hz or less. The question is when is the content B, and when is the content D? Since the only definition that includes emissions with the letter D as their third symbol is data, we have to conclude that the third symbol is a D when the emissions contains telemetry, telecommand and computer communications. There are three definitions that have emissions designators where the third symbol is a B. Those are: CW, MCW, and RTTY. RTTY is narrow-band direct-printing telegraphy. Part 2 defines telegraphy as: a form of telecommunication in which the transmitted information is intended to be recorded on arrival as a graphic document; the transmitted information may sometimes be presented in an alternative form or may be stored for subsequent use. A graphic document records information in a permanent form and is capable of being filed and consulted; it may take the form of written or printed matter or of a fixed image. The third symbol B is defined as telegraphy for automatic reception. There are 3 third symbols that are considered telegraphy A - telegraphy for aural reception B - telegraphy for automatic receptionC - facsimile - form of telegraphy for the transmission of fixed images From history we know that RTTY traditionally has been a system where the operator types at one end, and the characters and control appear at the other end. Facsimile traditionally works in a similar fashion. An operator sends a picture to a machine which reproduces the picture at the other end. I am not sure why any digital mode with a human operator at each end sending text would not qualify as telegraphy for automatic reception and thus be exempt from the 500 Hz maximum occupied bandwidth limit. Telemetry and telecommand are well defined, data is undefined and I am not sure what constitutes computer communication and thus I am not sure when the third symbol has to be a D. Perhaps the third symbol is a D when there is no human operator in control of the station, and a computer is controlling communication. That would make the most sense to me. So to summarize, if you use an outboard controller like the SCS PTC II and a SSB transmitter, and you are a computer is handling communication without a human operator, then you must limit your maximum occupied bandwidh to 500 Hz or less. If you are sending images, you must limit your occupied bandwidth to 500Hz or less. Just a note, the original petition that I wrote asked for authorization to send images in the RTTY/Data subbands in the 80 thorugh 10-meter bands. I added the 500 Hz maximum occupied bandwidth to make the suggestion more palatable to the general Amateur radio public. I did not ask the FCC to change the definition of data, I asked them to modify 97.305. They chose instead to modify the definition of data, and add J2D to the list of emissions that must have an occupied bandwidth of 500 Hz or less. The ARRL and W5SMM wrote comments to my petition. I think the FCC got the idea of the 500Hz limit for J2D from them, although that was not their intention. You can read those comments at http://gullfoss2.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6516213520 (see section III) and http://gullfoss2.fcc.gov/prod/ecfs/retrieve.cgi?native_or_pdf=pdfid_document=6516088425 The FCC response is at http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-149A1.pdf (see paragraph 15. 73, Mark N5RFX it seems to me is this regulation by emission designators. If I have a black box, and FSK at RF comes out of it, who's to say whether what is inside is a frequency-shifted oscillator or a SSB generator being fed with FSK audio tones. Or some frequency synthesis scheme that is able to shift between two different divisors. The rules seem to say that I can use 850 Hz RTTY if I directly shift the VFO, but
Re: [digitalradio] Part of the problem
First to the list, I am sorry about the fonts and alignment of that post. I am not sure what happened. Rick, You notice where the J2D should be emissions A1C, F2C, J2C and J3C having an occupied bandwidth of 500 Hz or less, and J2D. NOT emissions A1C, F2C, J2C, J3C, and emissions A1C, F2C, J2C and J3C and J2D having an occupied bandwidth of 500 Hz or less, The ARRL was saying that when sending images digitally the emission is always J2D. In other words everything is data. The FCC could have easily said, yes this is true, but they missed one procdural thing. When the comment period started, my peitition was ALREADY graneted. So the question was not whether image emissions needed authorization, it was how were image emissions going to be authorized. Your analysis is correct. Of course I did my homework well before I submitted the petition and received advice. I had my ducks in line so to speak. It is not a great big staff that reviews these petitions. I have a feeling some summer interns worked on this one. There were just too many small mistakes. I am happy with the outcome, but I am not sure the J2D thing can stand up to scrutiny, but we will see. 73, Mark N5RFX At 06:46 PM 11/17/2006, you wrote: Mark, In reviewing the comments some things stand out that I missed before: 1. In your petition you recommended the wording for the definition for data to be changed: emissions A1C, F2C, J2C and J3C having an occupied bandwidth of 500 Hz or less, and J2D. In the ARRL comments to your petition, they felt that just having J2D and without the other C type FAX modes would be adequate for sending image: This version would have the effect of permitting digital images to be transmitted in a computer communication within the existing symbol rates, which are given in §97.307(f). Since J2D data was already permitted in the CW/RTTY area (as an example, all of 80 meters, but not 75 meters) how could their suggestion make it possible to begin sending FAX on this subband when in the past the FCC has said that we really don't have that authority to do so? What am I missing? 2. They sure ignored Victor Poor's comments in their final decision. 3. When all is said and done, the FCC says they want to advance the radio art and all, but then make it impossible to do so with digital data modes. There is some kind of disconnect. And I do not blame this all on the Commissioners. My view is that they are like jurists, trying to make a final decision based upon the input from the public, and also their own engineers, who know the minutia of this kind of stuff. For example, to effectively delete the automatic forwarding area on 80 meters, without ever bringing this up, really should have been foreseen by the engineering expert advisors. Unless I am being unrealistic and the professional engineering advisors don't have the ear of the Commissioners. 73, Rick, KV9U
[digitalradio] FCC RO and J2D
I received a response from the FCC this morning about the J2D issue. The response was simply its on the list. This means that they know there is an issue. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Multi-media, Multi-mode, Cross-mode, Chat, Voice
We have to be pragmatic if we want to get this done. The fact is that bringing digital text emissions to the phone/image subbands on HF is not a popular proposal. We have to think of ways to make this palatable to the majority of Amateur Radio Operators. If there were some verbiage that we could come up with that would make digital text use secondary to phone/image use, then we might be able to sell the idea. We would have to create a regulation that would allow you to use digital text only in conjunction with a Phone/Image qso. Of course if the FCC enacts regulation by bandwidth, then we would do this through bandplanning, but I am not holding my breath. Part 90 has some areas where F3E is primary and F1D is secondary. If F3E causes interference to F1D, then the F1D station must accept that interference. If the F1D station interferes with a F3E station, then the F1D station must cease. Maybe this is a way to introduce digital text into the Phone/Image subbands, if the FCC rejects regulation by bandwidth. This is not the ideal way to approach this, but compromise rarely gives the optimum solution to a problem. The reason for the popularity of prohibiting digital text emissions in the phone/image bands is because there is a school of though that says it reduces the amount of stations using the subband. There is less contention for bandwidth. 73, Mark N5RFX We would certainly be using some type of text chat mode on that same channel with our voice nets---our european net members have already been doing that with AMD/8FSK-DTM/ARQ/PSK---but our USA net members are still locked out from fluid chat due to FCC's content/mode restrictions, left over from the mid-20th century era of radio. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] 3kHz or 500Hz Re: Updates on effect of FCC RO
Walt, Your examples are with like bandwidths. These channels were assigned for the purpose that you have mentioned, so any reduction in bandwidth would not provide any increase in efficiency. In other words you would still occupy the entire channel. With Amateur Radio this is not the case. We are not assigned channels (except 60 M) so any reduction in bandwidth may give us an increase in efficiency. Lets compare Pactor II and Pactor III under good conditions. http://www.scs-ptc.com/pactor.html tells us that on average PACTOR III give us a 3.5 X increase in data rate with 5 to 6 X the bandwidth. On good channels the increases are equal. This tells me that in the best case PACTOR II and PACTOR III are equally efficient, but on average Pactor II is more efficient. A single PIII QSO would occupy 2.4 KHz for less time than PII would occupy 400Hz of spectrum, if you calculate Hz/sec, PII will win in both the good channel and average channel case. Speed alone cannot be the only factor when considering efficiency. The wider bandwidth of PIII may make the transmission more robust. We also see that with Olivia and MT63, but we need to quantify that improvement. When we start spreading signals in a power limited system like Amateur Radio, we need to be aware of the affects of the Crest Factor (CF). I think we will be able to use emissions with bandwidths greater than 500Hz in the RTTY/Data subbands, but it is very interesting to me to find how popular limiting the maximum occupied bandwidth to 500Hz actually is with the general ARS population. 73, Mark N5RFX Ah ha...well Bonnie I see that I am not the only one who is looking at the overall picture of band usage. Here is an example of what I saw in the military... SSB voice took 10 minutes to pass a 100 word message between really seasoned radio operators on an HF channel typical of most Q4-5 amateur radio QSOs. When they went to 300 baud text data, they send the same message in 2 or 3 minutes and sometimes 3 or 4 when they had to repeat the message...this was again with Q4-5 signals. The modem was not much more than a Bell 103 modem. With a MIL-STD-188-110 16 tone modem at 2400 baud, the message took 1 or 2 minutes and only every 5-6 messages was a it necessary to repeat a message. The band/channel usage went from 1=10 to 9 0r 9=10...almost a ten fold increase in band/channel usage. Today those same units are using 9600 BPS data and sending one page of text in a couple of minutes or sometimes booking messages and sending 20-50 messages at one time. The higher the throughput and mode robust the mode, the less channel usage there is going to be at a fixed amount of data. __._,_.___ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) SPONSORED LINKS Ham radio Ham radio antenna Ham radio store Digital voice Digital voice recorder mp3 Your email settings: Individual Email|Traditional Change settings via the Web (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe __,_._,___
Re: [digitalradio] 3kHz or 500Hz Re: Updates on effect of FCC RO
You guys are going to have to do the math for me. I do understand that faster throughputs mean that I will be occupying a certain amount of spectrum for a shorter period of time, but the cost is bandwidth. Unless the increase in throughput is greater than the increase in bandwidth, I don't always see the wider protocol being more efficient. I do understand trading bandwidth for accuracy and that can be added to the equation too, but that really only applies to forwarding messages, not keyboard to keyboard QSOs. 73, Mark N5RFX Quoting expeditionradio [EMAIL PROTECTED]: There's another way to look at spectrum use. It is better to use a 3kHz bandwith for 10 minutes than to use a 500Hz bandwidth for 1 hour to pass the same traffic. On HF, with short propagation openings, it is better to be able to quickly send the message. On my opinion, this is a crucial point. Using the same kind (and not larger messages) the channel will be free sooner, and the info WILL pass. That's one of the PACTOR III vs PACTOR II adventages already in use. __._,_.___ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) SPONSORED LINKS Ham radio Ham radio antenna Ham radio store Digital voice Digital voice recorder mp3 Your email settings: Individual Email|Traditional Change settings via the Web (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe __,_._,___
Re: [digitalradio] 3kHz or 500Hz Re: Updates on effect of FCC RO
If the protocol can send the info faster than I can type, then I think it does make a difference. 73, Mark N5RFX I don't think keyboard to keyboard has anything to do with it. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Updates on effect of FCC RO
After some off the list discussion, I retract the statement below. For an emission to be J2B it must be narrowband direct printing telegraphy. Narrowband is the key word and has been defined for us as 500Hz. The remaining question is did the FCC intend to include J2D in the list of 500Hz maximum bandwidth emissions? 73, Mark N5RRX All of the modes that claim to be J2D are really J2B when sending text. When sending images they would be J2C and fall under the 500 Hz maximum occupied bandwidth limit. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] 500Hz Limit? Re: Updates on effect of FCC RO
Below 30 MHz it would be a very popular step, but I agree that this most likely was not the intention of the FCC. 73, Mark N5RFX It would be a huge step backward for the Amateur Radio Service in USA if FCC were to limit Data transmissions to less than 500Hz bandwidth Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Updates on effect of FCC RO
Rick, The text in the RO indicates that the 500Hz maximum occupied bandwidth only applies to the new emissions designators added to the definition of data. and the affected bands are below 30 MHz. This is what I asked for in my petition. However, the FCC did put J2D in the list of 500Hz maximum occupied bandwidth emissions designators. I am not sure why this was added, or if it was a mistake. My guess is that it should have read: emissions A1C, F1C, F2C, J2C, and J3C having an occupied bandwidth of 500 Hz or less when transmitted on an amateur service frequency below 30 MHz, and J2D. I think the and J2D ended up in the wrong spot. Unless the list is changed, the list of 500Hz maximum occupied bandwidth emissions designators are: A1C, F1C, F2C, J2C, J3C, and J2D. The other emissions designators which do not fall under the 500 Hz maximum occupied bandwidth are those with: A, C, D, F, G, H, J or R as the first symbol; 1 as the second symbol; D as the third symbol, so a general statement that they are no longer going to permit ANY wide band digital modes in the CW/data sub band is incorrect. Only images and digital signals input into the mic or accessory jack of a SSB transmitter and transmitted below 30 MHz are under the 500Hz limit. Even if this was a mistake, I think you will find a majority of amateur radio operators are happy with this decision. Why did not the FCC allow wide data modes in the phone area other than the usual image modes? No one asked for that in PR Docket 04-140. No one has asked because this will be a very unpopular request with the majority of the amateur radio community. This is one reason that the ARRL petition to regulate by bandwidth is so unpopular. 73, Mark N5RFX Am I reading this correctly to say that they are no longer going to permit ANY wide band digital modes in the CW/data sub band? I got the impression in the RO that the FCC meant that any new modes using image came under the 500 Hz requireement. But this seems to say that basically no modes can exceed 500 Hz in the RTTY/Data/CW sub bands. __._,_.___ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) SPONSORED LINKS Ham radio Ham radio antenna Ham radio store Digital voice Digital voice recorder mp3 Your email settings: Individual Email|Traditional Change settings via the Web (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe __,_._,___
Re: [digitalradio] Updates on effect of FCC RO
Rick, All of the modes that claim to be J2D are really J2B when sending text. When sending images they would be J2C and fall under the 500 Hz maximum occupied bandwidth limit. 73, Mark N5RFX OK, Mark, then it does look like we are not going to be able to use the wider modes in the CW/RTTY/Data area. I am not sure what wide modes you are referring to that are not sent with J2D as all of the ones I can think of are done with injecting tones into an SSB transmitter. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] What is an image and what is data
The answers to these questions about what is an image is simple in one respect. The current FCC rules allow digital emissions throughout the 160 through 10 meter bands. This is true because emissions that have a 1 or a 2 as the second symbol of the emissions designator are allowed everywhere. It is the content of the digital emissions that is segregated, and this is the third symbol. So if the content of you message is data, then the emission that you are using had a D as the third symbol. If the content of your emission is an image then the third symbol is a C. If the content of your message is telegraphy for automatic reception, then the third symbol is a B. What is telegraphy? Telegraphy in this case is defined in part 2 as: a form of telecommunication for the transmission of written matter by the use of a signal code. Facsimle is also a form of telegraphy, but is for the transmission of images. What is complex is capturing an emission and determining if it is an image or data. Win DRM is a good example. You can send F1D and F1C with WinDRM, but unless you decode it, you cannot tell from the emission whether it is an image or data. 73, Mark N5RFX __._,_.___ Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) SPONSORED LINKS Ham radio Ham radio antenna Ham radio store Digital voice Digital voice recorder mp3 Your email settings: Individual Email|Traditional Change settings via the Web (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe __,_._,___
Re: [digitalradio] What is an image and what is data: correction
This should read Data emissions in the Phone/Image bands. 73, N5RFX At 10:46 AM 10/15/2006, N5RFXwrote: Allowing Data emissions in the RTTY/Phone bands. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] What is an image and what is data
Bill, Part 2 of the FCC rules section 2.1 has definitions. Look at the link below. http://frwebgate.access.gpo.gov/cgi-bin/get-cfr.cgi?TITLE=47PART=2SECTION=1YEAR=2000TYPE=TEXT I was not quoting; thus the absence of quotation marks, but you can see the definitions of Telegraphy and Facsimile in this document. 73, Mark N5RFX At 04:20 PM 10/15/2006, you wrote: X-Yahoo-Newman-Property:groups-email-ff Content-Type: multipart/alternative; boundary=cNz5hW0qAsol3cLAuE2A15GDZ8tSdCEbs7UOJDo Mark Forgive me, but your post (below) thoroughly confuses me. The end of the first paragraph refers to Part 2. --Part 2 of what?- The (assumed to be a quote) in a different font seems to be ambiguous in regard to mode, since it appears to be applicable to both wired and radiated modes. Please help, particularly with regard to the definitions of telegraphy and Telecommunication. The (assumed) quote does not appear to be an official document, because of certain internal references to specific programs. Thanks-Bill-W4BSG Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] What is an image and what is data
I agree, and the FCC is accepting petitions. 73, Mark N5RFX But I really do believe that we need to be able to move data on the phone frequencies. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] WinDRM and new USA rules?
I'm not so sure of that. As I understand it, D means telemetry or telecommand. D - Data transmission, telemetry, telecommand No I am not out to banish Pactor III, but I am wondering why the FCC included J2D in the list of 500Hz maximum occupied bandwidth modes. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Digipan 2.0 Sample Rate ??
Is your soundcard new too? You probably have a soundcard with drivers that don't quite have the same sampling rate for tx and rx. The way I handle this with MixW is I generate a tone and measure it on a frequency counter. I adjust the TX sampling rate until the frequency is correct. For receive I generate a tone, and adjust the rx sampling rate until it appears in the correct spot on the waterfall. You could use WWV to the RX adjustment too. You could use USB and go to WWV with a offset and make sure the signal is at the proper place on the water fall. If digipan will allow full duplex you can then do a loopback (line in and line out) and generate a tone (or PSK signal) and adjust the sampling rate for TX until it appears in the proper place on the water fall. 73, Mark N5RFX The manual says to change the sample rate. I'm not clear if I should be changing my TRANSMIT or my RECIEVE as well as by how much? Can anyone help? I didn't have this issue with my old computer. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] tell me again
The OTHER GUY makes sure that he transmits Mark on the higher RF frequency and Space of the lower RF frequency with a 170 Hz shift. You do not care whether he does this on USB or LSB. At your end YOUR equipment requires 2125 and 2295 for Mark and Space respectively, it is YOUR responsibility to tune and set your rig for LSB for an audio output with the proper frequencies. If this is done, then the RF frequency for Mark will be the same for both stations and is the proper frequency to report for logging, and setting up a sched. Some software (MiXW) would require the receiving end to be in USB for this same scenario. What I think happens with new RTTY users who use MixW, are told that AFSK RTTY is ALWAYS on LSB, so when they send, their tones are reversed. With MixW, the default is to send and receive USB. This default puts the Mark and Space RF frequencies in the proper place. An ST-6 user would still send and receive on LSB. I looked back at the archive, we discusses this in October of 2005, I thought I was having deja vu. The ST-6 is looking for a mark tone of 2125 and a space of 2295. If for some reason the other guy is on USB but still with 2125 2295 tones I can flip the reverses switch and copy him just fine. If he is using a TNC that has the 200Hz shift I can't copy. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Reverse is not a new concept
The EU example is different from what we have been discussing. The EU stations are transmitting Mark as the lower RF frequency. We have been talking about transmitting the Mark as the upper RF frequency and using USB. This is what MixW allows. If it was possible with the older equipment, I wonder why USB never caught on until the sound card modes? Maybe it was not to confuse folks who incorrectly report the dial frequency for RTTY contacts instead of the Mark frequency. 73, Mark N5RFX The main problem with operating reverse would be that your dial frequency would be different from most other operators. If you wanted to work EU or other stations using low and/or reversed tones, you would have used this feature. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] tell me again
Your ST-6 has no idea what RF frequencies the Mark and Space at. You tune until you get 2125 for Mark, then if the shift is 170Hz you will be looking for 2295 for Space. If the Mark is sent with a high RF frequency with respect to the Space, then you need to be on LSB. We have discussed on this very reflector, and I know you understand this. If both parties give the Mark RF frequency as the operating frequency, then everything is ok. Sorry about the 200 Hz, but that is the Pactor and 300 baud AX.25 standard. I know some TNCs (PK-232) are set up for an AFSK shift of 200Hz for RTTY. 73, Mark N5RFX This is a problem for me as my ST-6 terminal unit does care what the mark and space frequencies is. Off be more then a few Hz and I can't copy. Same holds true for the 200 Hz shift TNC - can't copy them. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Upper Sideband as International Standard
Rick, That could be, but remember that the shift was 850 Hz. You had to choose frequencies within the passband of the receiver audio, and make sure that harmonics were outside of the passband. 2125 was chosen as the Mark audio frequency. The second harmonic of 2125 is well outside the audio passband of the receiver. If you were to go down 850Hz you would have 1275. The second harmonic of 1275 is 2550, well within the receiver passband and very close to 2125. Remember back then RTTY demodulators were pretty loose. So it made sense to go from 2125 to 2975. That is the reason for LSB. The VFO in the transmitter could shift either direction. When the shift went to 170 Hz this became less of a problem. For narrowband digital, I still tend to choose frequencies above 1500 Hz, so that if I do have harmonics, they should be out of the passband. I have been able to generate harmonics with AFSK modes by choosing low audio frequencies, and providing too much drive from the sound card. Some soundcards do a fine job of producing harmonics. 73, Mark N5RFX When AFSK came along I wonder if it is because it was started on the lower bands more commonly and since they only had LSB available on some rigs, they chose to make LSB the default sideband choice? Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Upper Sideband as International Standard
Rick, I wasn't around back then but from what I have read, the standard for RTTY was set that the Mark was the high RF frequency and the Space the low RF frequency. To avoid problems with audio harmonics and the fact that some rigs could not handle 2975, LSB had to be used. Most demodulators would treat the absence of Mark as Space. I wish I could find the article, but I remember reading how one amateur got around the FCC regulations in the early days before FSK RTTY was authorized by only decoding the presence and absence of Mark, so it was like decoding CW. The LSB thing is just one of those things that happened because of equipment limitations, and then got a life of its own, like LSB for phone below 20 meters. MixW was the first program with RTTY that I had used that send AFSK with the Mark high and the Space low. I thought, gee about time. 73, Mark N5RFX Would LSB be a requirement of 850 Hz shift if they could have chosen either sideband? Why couldn't they select USB with the audio tones reversed from LSB? This would have made the two RF frequencies normal to FSK RTTY with a mark of 2975 and a space of 2125. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Upper Sideband as International Standard
Here are a couple of interesting RTTY History articles. http://www.rtty.com/history/w6owp.htm http://www.hertzmail.com/rtty/ttyinfo1.pdf 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Upper Sideband as International Standard
Yep, it is probably one of those things that was set in concrete and never changed. But it really doesn't matter how you want to do it as long as Mark is the higher RF frequency, since that is the frequency you give as your operating frequency for RTTY. Now programs like MixW allow you to stay on USB if you want. If you have to set your rig for lower sideband, it has that option too. 73, Mark N5RFX The RF mark frequency had to be high (on HF) since they normally used a capacitor to pull the FSK VFO down. One of my ham peers who was licensed the same year as I was (1963) indicated that to his knowledge, all AFSK tones were set up as mark tone low on the one generators. It could be a chicken and egg situation, but that would only work with LSB to get the mark high on RF. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] tell me again
The reason that LSB historically has been used for RTTY was that the equipment in the early days had difficulty dealing with FSK. On the demodulator side you had to choose frequencies that would not produce harmonics to fool the demodulator. Back then the frequency shift was 850Hz, and it was decided that the optimal demodulator frequencies were 2125 (mark) and 2975 (space). Mark is the idling frequency, so many demodulators had the ability to look at the absence of mark as space. To make the transmitter transmit FSK you added a capacitor to your VFO, and switch this capacitor in and out for mark and space. The standard was to have the mark be the high RF frequency, and the space be the low RF frequency. If the demodulator was looking for a 2125 mark, and the transmitter was transmitting the high RF frequency, LSB had to be used in the receiver. Today, we don't have these limitations. We do need a standard, and the standard is still to transmit the mark as the high frequency, and the space as the low frequency. The shift for FSK is now 170 Hz. Terminal units that used filter techniques, had filters set up for 2125 and 2295 Hz for Mark and Space respectively. With these standards it was still a requirement to receive on LSB. Today most sound card programs don't care what the mark and space frequencies are for demodulation, as long as the shift is correct. This allows us to shift to the more intuitive USB mode. Mark is transmitted as the high RF frequency,and Space is the low RF frequency. On the demodulator the high audio frequency and space is the low audio frequency. This is much easier to understand. 73, Mark N5RFX I ask this before but tell me again why al the sound card modes are on USB when all the *pre* sound card modes (RTTY, PACKET, AMTOR PACTOR and others) are all LSB Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: digital modes and THE RADIO
Jim, I agree, but we are talking about a test. The test signal would have to have a signal that either sweeps or is shifted in frequency. This would be a test like a two tone test. A two tone test is not a real world test, but it is made with very specific signals and the results are well known. I think we would have to approach group delay the same way. Through equalization most transmitter/receiver anomalies can be corrected. Non-linear effects of the analog circuits cannot be necessarily corrected, but the signals can be designed to reduce their effects. MT63 is a good example. 64 tones that can be run into an amateur radio at full power with third order IM products that are 23 dB down, and not cause excessive bandwidth outside of the necessary bandwidth. I have some spectrum analyzer plots of this, but cannot find them right now, and my spectrum analyzer is in the field. As soon as I get it back I will make some tests. Even PSK31 run at full power really does not cause the IM problems that most people claim. Most of the IM problems happen in the receiver, or in over driven analog sound card and transmitter audio circuits. 73, Mark N5RFX While they may be sinusoids, they are not steady state. The tones are switched and their phase may change depending on the modulation. An example would be the first cycle of a sinusoid applied to capacitor or an inductor. You will get some distortion. How much is the question. Phase changes also require a high slew rate capability in order to not be distorted. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: digital modes and THE RADIO
I agree and this concern has been considered in this thread. The modem used in the MIL STD 188-110 MARS ALE implementation was modified to accommodate amateur rigs. With the exception of SDR radios, COTS radios will typically have a 2.4 to 2.7 KHz transmit bandwidth. I agree that if these radios are to be used, then this bandwidth limitation needs to be taken into consideration.This is why we test these sort of things. I think for HF bandwidths of 3 KHz are most appropriate. That is just my opinion. My main concern is that as higher performance modems are discussed you can't just forget the RADIOs they are connected to. In the end, we are talking about a total system being required to maximize throughput. Not just wider bandwidths, and more tones. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Digital Radio Mundial ?
WinDRM - HF Digital Radio Mondiale http://n1su.com/windrm/ WinDRM is a digital mode on HF that lets you do digital voice, image and data. You can transfer data at almost 1KB/s without using proprietary hardware! SDR1000 http://www.flex-radio.com/ is a product of FlexRadio Systems and is hardware and open source software to make a software defined radio. Presentations were made at the TAPR DCC on both products. HPSDR http://hpsdr.org/ was also another SDR project presented at the TAPR DCC. This project included open hardware and software. 73, Mark N5RFX At 09:01 PM 9/19/2006, you wrote: Apparently the just completed TAPR conference featured Digital Radio Mundial and the SDR1000 and wowed many of those in attendance. Anyone know more about the application ? Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] digital modes and THE RADIO
Jose, I think you are correct. SDR allows you to make the radio for whatever type of modulation/protocol you want to send. As you say, if that modulation/protocol changes, just change the firmware. I think that this will be the next homebrew revolution. FPGA's are getting very cheap and easy to program. 73, Mark N5RFX So far, I see a Software Defined Radio as the solution. You may, then, define the bandwidth you NEED on the fly. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] digital modes and THE RADIO
Rick, Yes group delay is an issue, but with adaptive training this too can be overcome. Sound cards, or external modems using DSP or preferably FPGA's would be a fine compliment to most amateur gear. The SDR (software defined radio) that Jose mentioned will be the best solution going forward for more exotic modems. These modems would be an integral part of the radio. I was looking for a good way to test group delay, and was thinking of generating an FM signal with 3 to 5 KHz deviation and looking for an envelope at the output of the receiver. Does that sound ok? The signal generator is an HP 5640B. 73, Mark N5RFX Another thing that I came across in my web searching was that amateur equipment generally has group delays that make it difficult to even employ some of the modems we have been discussing. Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: digital modes and THE RADIO
I guess my point is, do you know what your passband is in your radio. Are the 3 db points really at 300 and 2700 Hz? Are there any fluctuations at other frequencies in the passband? What about phase variances throughout the passband? I have made measurements on my IC-746. I set the RX filter to 3 KHz smooth. The response curve is at http://home.comcast.net/~mdmiller7/im3/rx_smooth.jpg I had to use a trend line because I could not take an infinite number of points with this test setup, but the 3 dB bandwidth was 3.055kHz, Setting this same filter to sharp gave the repose at http://home.comcast.net/~mdmiller7/im3/rx_sharp.jpg .The 3 dB bandwidth was 3.087kHz. The receive side seemed pretty smooth, the transmit side was a bit bumpy. The 746 pro has 3 transmit bandwidths, wide, medium, and narrow. The response curve for wide is at http://home.comcast.net/~mdmiller7/im3/tx_wide.jpg . The 3 dB bandwidth was 2.640kHz. As far as intermod goes, this transmitter's linearity in my opinion is acceptable at 40 to 50 watts. I ran a two tone test at 100W PEP which is shown at http://home.comcast.net/~mdmiller7/im3/746PRO100W.jpg . At 50 watts the display is at http://home.comcast.net/~mdmiller7/im3/746PRO50W.jpg , and at 40 watts http://home.comcast.net/~mdmiller7/im3/746PRO40W.jpg . I need to find a way to show group delay, I am working on that now. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] 16QPSK Modulation and Baud
Can you or anyone explain why they need this high speed on HF when even 300 baud is pushing the limit on the higher HF bands? I think this limit only applies to protocols that do not make use of FEC, redundancy and adaptive training. Adaptive training may be the most important element. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] 16QPSK Modulation and Baud
MIL-STD 188-141 http://tracebase.nmsu.edu/hf/standards/MIL/141Bn1.pdf . MIL-STD 188-110 http://tracebase.nmsu.edu/hf/standards/MIL/188-110B.pdf Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] Baycom Modem
I am looking for a Baycom Modem. If anyone has one they would like to part with please email me. [EMAIL PROTECTED] 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/digitalradio/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] ARQ sound card modes
My measurements on 10 Mhz show that MT63 has 20% less errors than PSK63 on the same channel. The is not enough to offset the negative points. Very interesting. It would seem that MT63 would better remain a broadcast mode like Amtor Mode B or PACTOR FEC. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] 188-110B Adaptive Equalization
Steve, Is there adaptive equalization used in the PCALE or MARSALE implementation of 188-110A or B? 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] 188-110B Adaptive Equalization
This is needed, absolutely mandatory, to mitigate the fading multipath HF channel. Bob, Thanks. I have not had a opportunity to send images with 188-110, but after reading the specification, I thought adaptive equalization would be necessary. I look forward to sending images. I have been hanging out of the 20 meter channels hopping that conditions would be right to do some testing. So far I have only used the messaging in 188-141 which I don't believe has the training sequence necessary for adaptive equalization. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] 188-110B
After reading the spec at http://tracebase.nmsu.edu/hf/standards/MIL/188-110B.pdf I see from a high level how the fixed frequency modem works. Table XIX in the document gives a great summary. I have taken a snapshot of that table an posted it at http://home.comcast.net/~mdmiller7/ale/table_xix.jpg . Also I have pulled off a block diagram that is very helpful at http://home.comcast.net/~mdmiller7/ale/block_diagram.jpg . Remeber that the final symbol rate is always 2400 bps. I have not looked at how the lower symbol rates in Mars ALE affects this explaination. In table XIX the information rate is the actual bps throughput. The coding rate is the ratio of input bits to output bits in the FEC encoder. The channel rate is the symbol rate after FEC and Interleaving. The bits/channel symbol tells you what to divide the channel rate by to get the symbol bits per second before symbol formation. The 8-phase symbols/channel symbol tells how many 8 phase symbols there are per channel symbol. This number is multiplied by the symbol bits per second to determine the symbols per second after symbol formation. The last two columns give the ratio of unknown to known 8 phase symbols. The unknown data is message information, the known data is training bits reserved for channel equalization. Starting with the information rates, here is flow. 4800 bps has no coding so the channel rate is 4800 bps. There are 3 bits per symbol. so the symbol bits per second before symbol formation is 1600 bps. There is 1 8 phase symbol per channel symbol, so there are 1600 channel symbols per second of known data. The ratio of unknown to known symbols is 32/16. so the known symbol rate is 1600/2 or 800 symbols per second. 1600 + 800 is 2400 symbols per second. 2400 bps has a coding rate of 1/2. This makes the channel rate 4800 bps (1 bit in gives you 2 bits out). 3 bits per symbol for 1600 bps. There is 1 8 phase symbol per channel symbol, so there are 1600 channel symbols per second of known data. The ratio of unknown to known symbols is 32/16. so the known symbol rate is 1600/2 or 800 symbols per second. 1600 + 800 is 2400 symbols per second. 1200 bps has a coding rate of 1/2. This makes the channel rate 2400 bps. 2 bits per symbol for 1200 bps. There is 1 8 phase symbol per channel symbol, so there are 1200 channel symbols per second of known data. The ratio of unknown to known symbols is 20/20. so the known symbol rate is 1200/1 or 1200 symbols per second. 1200 + 1200 is 2400 symbols per second. 600 bps has a coding rate of 1/2. This makes the channel rate 1200 bps. 1 bit per symbol for 1200 bps. There is 1 8 phase symbol per channel symbol, so there are 1200 channel symbols per second of known data. The ratio of unknown to known symbols is 20/20. so the known symbol rate is 1200/1 or 1200 symbols per second. 1200 + 1200 is 2400 symbols per second. 300 bps has a coding rate of 1/4. This is accomplished by repeating the coding twice. This makes the channel rate 1200 bps. 1 bit per symbol for 1200 bps. There is 1 8 phase symbol per channel symbol, so there are 1200 channel symbols per second of known data. The ratio of unknown to known symbols is 20/20. so the known symbol rate is 1200/1 or 1200 symbols per second. 1200 + 1200 is 2400 symbols per second. 150 bps has a coding rate of 1/8. This is accomplished by repeating the coding 4 times. This makes the channel rate 1200 bps. 1 bit per symbol for 1200 bps. There is 1 8 phase symbol per channel symbol, so there are 1200 channel symbols per second of known data. The ratio of unknown to known symbols is 20/20. so the known symbol rate is 1200/1 or 1200 symbols per second. 1200 + 1200 is 2400 symbols per second. 75 bps has a coding rate of 1/2. This makes the channel rate 150 bps. There are 2 bits per symbol for 75 bps. There are 32 8 phase symbol per channel symbol, so there are 2400 channel symbols per second of known data. All data is known data, so the symbol rate is 2400 bps. Now how well this all works remains to be seen. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] MIL-STD-188-141B
This standard may be found at http://tracebase.nmsu.edu/hf/standards/MIL/141Bn1.pdf . The single frequency modem is 8FSK running at 125 baud, 3 bits per symbol, 375 bits per second. A word is 24 bits. 3 bits are preamble, 21 bits are 7 bit characters. Each 24 bit word is encoded into a Golay (24, 12, 3) word totaling 48 bits plus one stuff bit, for a grand total of 49 bits. Thus every 3 characters is 49 bits. These 49 bit Golay words are repeated 3 times. (125 symbols/49 bits) * 3 = 7.75 characters per second * 7 = 53.6 bits per second. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[digitalradio] Packet Baud Rate
I went searching in my archives for some testing that was done in May of 2002 with Packet on HF using different Baud Rates and shifts. MixW has the capability of setting custom Baud Rates and Frequency shifts. Looking through my notes I noticed that we started with 100 Baud and a 60 Hz shift. I don't remember what other Baud rates and shifts we tried, but believe it or not, I do remember that 300 baud was just about right for AX.25 on HF. It may have something to do with Packet being frame oriented instead of character oriented. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: 188-110B
In the limited testing I've tried with image files, it works very well, indeed. Perhaps we can try exchanging some images next time we link. Bonnie, Great. Yes I have had some QRN here and the QSB has been a problem too., and none of the 8FKS signals I have seen have been super strong. WA3MEZ and I sent a few AMD and DTM messages back and forth. I had my radio scanning 20 meters, but not sounding, so you can find me there. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: ALE QRM is minimal
To be honest, using a high speed baud rate modem on HF and then encoding it to slow down the effective bps, seems the exact opposite of what is normally done with slower baud rate and higher order modulation to get the higher throughput. Rick, The actual BPS rate for 188-110B is 7200, for 188-141B it is 375. Higher order modulation is being used to get higher throughput. In the case of 188-110B you have in some cases much heavier use of FEC, redundancy and training. The question remains about the symbol times. We know that 300 baud packet is not useless on HF, although it is not optimized. I would like to re-conduct the experiments that were run in 2002 where the baud rate of HF packet was reduced. This time perhaps leaving the shift at 200 Hz and reducing the Baud rate to 100. I think however the long QSB will still be the major contributing factor to failure of packets. Since you have to decode the entire frame and get a good CRC, you are better off with short frame times. So far this has been the case with my QSO's using 188-141A. The shorter the message, the better the chance of success. Anyone for some 100 Baud packet? 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] USA; Baud Limit = 300 Symbols Per Second (HF Digital Data)
There is no equipment for the emission to be FSK or PSK. This should read there is no requirement for the emission to be FSK or PSK. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] USA; Baud Limit = 300 Symbols Per Second (HF Digital Data)
So what would be the difference if I transmitted 64 tones/carriers each modulated at 300 baud but transmitted them through one transmitter or 64 tones/carriers through 64 transmitters into one antenna? Walt, From a regulatory standpoint I don't think there is a problem. I think that Pawel Jalocha SP9VRC was concerned about occupying too large amount of bandwidth. Most U.S. Hams consider the RTTY/Data subbands to be narrow band . This is evident in the regulations. When the verbiage of 97.307(f)(3) was written (1977), there was only CW and FSK in the RTTY/Data Subbands,. In the Phone/Image subbands there were only analog emissions and they were AM, SSB and SSTV. The FCC tried to segregate the subbands by bandwidth, but there were some problems with AM and Fast Scan TV. Those groups mounted a campaign to stop the bandwidth effort at that time. The compromise was to keep the narrow/wide segregation, but do it without enumerating bandwidths. This is what we have today. Specifying a maximum Baud rate does not necessarily specify a maximum bandwidth. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] USA; Baud Limit = 300 Symbols Per Second (HF Digital Data)
I wasn't picking on Pawel at all...I just used MT63 as an example. Walt, I understand. My diatribe was to make the point that the occupied bandwidth has a bearing on the general acceptance of a mode. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Re: ALE QRM is minimal
The 2400 and 4800 baud is a composite baud rate for the mode/protocol NOT the discrete baud rate of any individual component of the waveform. Can you explain further? I saw that: MIL-STD-188-110A serial tone modem is just that, a single PSK carrier frequency that by the standard is locked at 1800hz using a constant 2400bps Symbol Rate. The symbol rate is 2400 Baud, so what makes this perform better than Packet at 300 Baud? 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: ALE QRM is minimal
If I gave you some parameters of a waveform, what would you use to base your measurement of baud rate? I would look at the data, and see how it is modulated into an analog waveform. For FSK we know that a 1 produces one symbol, and a 0 another symbol. MFSK16 the symbols represent 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 4 bits per symbol. For MT63 there are 64 bits per symbol. All 64 PSK signals combine to produce 1 waveform, just like a two tone, 3, tone or 4 tone test produce a waveform. The complex voice signal produces a waveform. PACTOR III uses the same logic...Up to 18 tones are used, spaced at 120 HZ. I can take a picture of the MT63 waveform and put it on the Internet if you like. Are you saying that the reason that packet performs so poorly is due the fact that it has no convolutional coding or interleaving? Yes, I would say that it is not as well suited for HF operation as other modes. All along what Walt and I have pointed out was that ISI becomes intolerable with difficult propagation conditions (e.g., doppler, polar flutter, etc.) with short symbol lengths. The longest symbol length possible for 300 baud is 1000/baud or 1000/300 = 3.33 ms. That is a very short pulse for HF. That is why Pactor chose 100 baud = 10 ms minimum pulse length (assuming they are continuous with no gaps). That 10 ms length is about the right amount, particularly with some DSP enhancements. You can overcome those issues by interleaving, convolutional encoding, redundancy, and spreading the signal. I would say the real reason why 100 baud may be the limiting for PACTOR III is not only the RF medium, but the radios that are using it. Amateur gear I am sure is not designed for low group delay distortion. If the baud rate of a waveform was 2400 as Steve has often mentioned, wouldn't the longest possible symbol length be about 0.42 ms? If this really can work on HF, it is completely contrary to what I have learned over the past few decades, particularly when Pactor was first on the scene. Even with extensive DSP, can you overcome that large of an ISI issue? Apparently you can, however we will never know unless we join MARS, or get the arcane 300 baud limit lifted. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Experiments with Fast HF PSK Soundcard Modem FS1052/MILSTD188-110
Bonnie, I will give it a shot if we can get a link between us. I can start scanning the 20 meter channels. 73, Mark N5RFX At 07:25 PM 9/1/2006, you wrote: On HF, I have used the fast PSK modem built into PCALE for sending JPG and GIF image files in the 20 meter phone band. FS-1052 / MIL STD 188-110. If anyone else would like to experiment with this, I'm interested in QSOs. It is a way for US hams to use this cool fast soundcard modem while avoiding the 300 baud speed limit put upon us in the data band. You will only need a transceiver capable of full 3kHz bandwidth, and the PCALE software. I'm using an Icom 756pro transceiver for this purpose. Bonnie KQ6XA [Non-text portions of this message have been removed] Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: ALE QRM is minimal
I'm not a lawyer either, Walt, but the 300 baud symbol rate limitation from §97.305(c)(3) below applies to a RTTY or data emission, not the individual components of that emission IMHO. I am not a lawyer either, but since the Walsh FEC code is 64 bits, the character rate is the same as the symbol rate. This means that each character is spread over all 64 tones. The symbol for each character is the entire waveform. The symbol rate is 10 baud for the entire waveform and this meets the requirements of §97.305(c)(3). I don't think the regulators really care however. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] USA; Baud Limit = 300 Symbols Per Second (HF Digital Data)
A-63 is legal on the ham bands, since each tone runs at 10 or 20 baud depending upon the commonly used versions of this mode, but has 64 tones, it would seem that it is running well over 300 baud when you consider the entire waveform. The entire waveform is one symbol. There are 10 symbols per second. The question that I need to be clear on is how many tones are running at the *same* time. 64 If the image sending operators are using QAM 64 (even if it doesn't work very well), I ask what is the baud rate of the individual tones and what is the total baud rate of the signal? Do the rules exempt voice and digital image from the 300 baud limit? If it does then my position would be that the FCC would welcome data modes with a total that exceeds 300 baud as long as individual tones do not. There are no enumerated maximum symbol rates in the Phone/Image subbands. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] ALE Keyboarding QSOs
Bonnie, Thanks. I found the definions for the AMD automatic message display DBM data block message DTM data text message It is interesting that you say that we were using 8FSK, I have observed the eight orthogonal tones on my waterfall before, and didn't know exactly what was producing them. Now I know. I probably won't be scanning, as my interest lies mainly with data comms, so I will hang out on 14109.5 and see what I log. Have you thought of doing a presentation for TAPR at the DCC in September? They are looking for speakers. 73, Mark N5RFX That was fun to make the ALE link and QSO with you today. It was surprising because your signal was very near the noise level. The 8FSK DTM ARQ seemed to work OK for text keyboarding back and forth. I'm glad you got your ALE system running there, and it is a pleasure to be your first ALE link. I added your callsign to my ALE address list. 73---Bonnie KQ6XA Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] ALE Keyboarding QSOs
At this time I am not sure what G4GUO is planning for PC-ALE in this regard. However under current FCC Part 97 Rules, ALE can be used in the digital sub bands for two-way digital data comm and in the Voice sub bands for SELCAL (and more but not digital data comm) and of course Digital Voice contacts after an ALE link, so time will tell. In MARS all of our digital data comm and Voice comm are on the same channels, at any moment we may switch between Voice and Data and back again, it is the nature of MARS net operations. This is true, but the guys on 14.233 are sending voice, image and data emissions for at least 2 years and no one has complained. Probably because no one can tell that they are doing it. I think that as long as the primary emissions are F1E, J2E, F1C, and J2C, no one will be cited for sending F1D or J2D. At least no one has been cited yet, and as far as I know, Mr. Hollingsworth has not even received a complaint. As long as we comply with 97.101, there should not be a problem. As I have said, everyone has turned a blind eye to the DRM and RDFT folks on 14.233. This is how it should be. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] The digital throughput challenge on HF
Rick, My explanation was for sinusoids not rectangular waves, our radios transmit sinusoids. You are correct about rectangular waves they would have a crest factor of 1 in linear terms or voltage terms, and 0B in non-linear or power terms. Yes MT63 has a crest factor of 13dB. It is very high. Lets deified a few power terms. Average or mean power is what you get when you multiply RMS voltage and current Peak Instantaneous power or peak power is what you get when you multiply peak instantaneous voltage and current. Peak Envelope power or PEP is what you get when you average the peak power over one RF cycle. Crest Factor is normally given in terms of voltage and is equal to the peak amplitude of a waveform divided by the RMS value. In terms of power this is the 10log(peak power/average power). The relationship between peak power and PEP in a sinusoid is 3 dB. This is very easy to prove. The relationship between peak voltage and RMS voltage is the square root of 2. 20 log of the square root of 2 is 3dB. Lets use a more complicated example. Lets say we generate a sinusoid from two equal amplitude tones. A two tone test. On an oscilloscope we observe that the peak voltage is 1 voltage unit for each tone which makes the peak power 1 power unit for each tone. The peak voltage of the envelope is 2 voltage units , so the peak power is 4 power units for the envelope. Each tone's RMS voltage is 1/square root of 2 or approximately .707 voltage units. The average power is the RMS voltage squared or .5 units. The total average power of the two tones is .5 + .5 or 1 unit. When using N tones to produce an envelope, PEP to average power ratio is 1/N. In this case it is .5, which means that the PEP is 2 units. Here are the relationships Peak power of the envelope = 4 PEP of the envelope = 2 Average power of the envelope = 1. PEP to average ratio = 3dB Peak to average ratio = 6 dB Difference = 3 dB This same example can be worked with any number of tones. Patrick used two programs if I remember correctly to calculate the peak and mean power for the various modes listed in the documentation for Multipsk. The two programs were Cool Edit Pro and Sox. In Cool Edit Pro the peak value given in the statistics is PEP. What Patrick is giving you is the PEP to average ratio. I have proven this in Cool Edit Pro using the 2 tone example above. 73, Mark N5RFX At 09:12 AM 8/24/2006, you wrote: How does the crest factor relate to the mean power vs the peak power? It doesn't seem correct to add 3 to that figure to come up with the crest factor. Patrick has the peak and mean power for the various modes listed in the documentation for Multipsk, but I am not clear how to convert them to crest factor. My understanding is that the peak power and average power of a rectangular wave is 1. It can't be correct to add 3 to that value to come up with 4, can it? And MT-63 which has a peak to average of 10 times has a crest factor of 13? If you want to broadcast a message from one to many, then the only practical alternative is to use a non-ARQ mode, typically with a large amount of FEC. While this is done on amateur frequencies for sending a bulletin, calling CQ, and having a roundtable, if your goal is to have accurate messaging, then I don't see any option other than a good ARQ system. If Clover II would have worked better, I would have considered keeping my HAL P-38 board. But it was not that good with weak signals. Also, the P-38 had serious problems with Pactor back then. I remember someone later criticizing me for not using a 386 computer for the card. But at that time the 386 was barely even invented and 286 machines were state of the art. 73, Rick, KV9U Mark Miller wrote: At 10:33 PM 8/23/2006, you wrote: I am not very knowledgeable on CRF (Crest Factors). Can you give us an idea of converting peak power/average power into CRF? Using powers, crest factor = Peak Instantaneous Power / Average Power. A more piratical way of measuring crest factor is (PEP/Average Power) + 3dB. I agree that ARQ has its benefits, but we still have to rely on the modem scheme. This was my point earlier, that we reach a limit because we are power and bandwidth limited. Because we are using HF frequencies, we pay a coding penalty. Also if we look at the broadcast nature of non-ARQ modes, it is apparent that they are much more efficient than ARQ modes. This does not mean that ARQ does not have its place, it certainly does. The more tools in the tool box the better. BTW I am an AMTOR OT myself. I remember when APLINK was used before unattended operation was allowed on HF. I miss keyboarding with AMTOR/PACTOR and CLOVER. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.orgTelnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/http://groups.yahoo.com/group
[digitalradio] The digital throughput challenge on HF
If I were a company technology officer, of a company who's purpose was developing communications technology...or the technology officer for amateur radio, I would be very dis-heartened at the data protocols/modes/modems produces as well as the HF E-Mail applications developed. None are really as robust as the should/could be, none of the sound card modes have the throughput that they should and there are is no really good HF E-Mail program that is based on the capability of operating stand-alone without using the Internet. Walt, You have pointed out a basic principle with respect to data throughput. Throughput is a function of bandwidth, power, and coding. With amateur HF we are power, and bandwidth limited. The nature of the media we are opening in makes forward error correction a must, thus we suffer a loss of throughput because of coding. The very robust modes like MT63 and Olivia require interleaving and convolutional coding. Compare MT63 and Olivia with RDFT or amateur DRM. RDFT and DRM are great modes, but requires a fairly high S/N ratio. The challenge is there, but the solution is far from easy. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] The digital throughput challenge on HF
At 04:29 PM 8/23/2006, you wrote: It in deed would. That is the reason Pactor and Amtor work so well. It's the AQR - even with the hi S/N needed. There is some value to ARQ, I wonder how we would quantify the advantage? In a point to point link I think it would be easy, but in a point to multipoint network, I think the value is significantly diminished. From an efficiency standpoint, broadcast modes like soundcard modes are very efficient. Point to point modes can be very reliable and very accurate, but very inefficient. I am not sure how one quantifies these differences. When it comes to speed and or throughput, we have the bandwidth, power, and coding barrier with which we much deal. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] The digital throughput challenge on HF
Note also in Figure 6, the real world test by using distance on 80 meters daytime. The worst performance was by Amtor, followed by Pactor 1 and closely by PSK31. The best performer was RTTY at these slow speeds and he gives his explanation as why he believes this occurs. It sounds reasonable to me. And also note that the non-ARQ modes always had some errors and the ARQ modes were error free. Rick, If I boil your argument to 2 points it would be that the advantages of the Pactor modes are ARQ and low crest factors? 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] The digital throughput challenge on HF
At 10:33 PM 8/23/2006, you wrote: I am not very knowledgeable on CRF (Crest Factors). Can you give us an idea of converting peak power/average power into CRF? Using powers, crest factor = Peak Instantaneous Power / Average Power. A more piratical way of measuring crest factor is (PEP/Average Power) + 3dB. I agree that ARQ has its benefits, but we still have to rely on the modem scheme. This was my point earlier, that we reach a limit because we are power and bandwidth limited. Because we are using HF frequencies, we pay a coding penalty. Also if we look at the broadcast nature of non-ARQ modes, it is apparent that they are much more efficient than ARQ modes. This does not mean that ARQ does not have its place, it certainly does. The more tools in the tool box the better. BTW I am an AMTOR OT myself. I remember when APLINK was used before unattended operation was allowed on HF. I miss keyboarding with AMTOR/PACTOR and CLOVER. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Emission types
I am looking for sound card digital mode software that will allow data to be entered via the serial port for transmitting, and for receive data to be brought out of a serial port. I would imagine these would be Linux applications. My purpose in doing this is to do some BER measurements . My test equipment uses RS-232. Maybe there is an RS-232 ASCII to keyboard converter? Looking for suggestions. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Recommendations on FAX
At 09:55 PM 7/28/2006, KV9U wrote: A low cost scanner could be used to scan the image and then convert to bmp file format. Any suggestions on whether this is feasible? Scanning the image sounds like a good idea. The image could be converted from .bmp to .jp2 and sent using HamPal or DigTRX. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Recommendations on FAX
Apparently the basic fax mode is only half duplex. The circuit I saw was a basic hybrid to separate the two wire telephone line into send/receive and to sense when the local fax was sending to trigger the radio (VOX) There is a good discussion of facsimile theory at http://electronics.howstuffworks.com/framed.htm?parent=fax-machine.htmurl=http://home.maine.rr.com/randylinscott/fax.htm The communication between two fax machines is outlined a little more than 3/4 of the way down the page. It appears to be full duplex. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Recommendations on FAX
Are you able to put your hands on the info by chance? HAL has a system that allows fax over radio: http://www.halcomm.com/docs/fax4100.pdf 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Recommendations on FAX
The individual wanting to do this, is primarily interested in running two bands (e.g., 2 meters/440) with full duplex. Well if it was absolutely necessary to use telephone fax machines, then at the originating end you would need a device that supplies -48 volts to the fax machine telephone interface, and can sense when the originating fax machine goes off hook. This device would then key the transmitter. At the answering end, a device would have to sense when the receiver breaks squelch and would have to provide the 20 Hz ring signal to the answering fax machine, sense off-hook, and key the transmitter.. When the fax is completed the originating end would go on-hook and the originating device would have to de-key the transmitter. At the answering end, the device would sense squelch, go on-hook and de-key the transmitter. A start would be the device like http://www.jkaudio.com/tap-1.htm with the addition of the transmitter and receiver control circuitry. A good article on telephone interfacing is at http://www.tkk.fi/Misc/Electronics/circuits/teleinterface.html#audioint This sounds like an interesting project, however there are programs set up to send high quality digital images, ie WinDRM, HamPal, and DigTRX. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Digital Video on 12.5khz channel
At 06:05 PM 6/8/2006, you wrote: It would be of no use to the US hams as we are limited to 5KHz on 2 meters. Joe Ivey W4JSI Not true. For 2 meters 97.307 (f) (5) applies: A RTTY, data or multiplexed emission using a specified digital code listed in http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html#309§97.309(a) of this Part may be transmitted. The symbol rate must not exceed 19.6 kilobauds. A RTTY, data or multiplexed emission using an unspecified digital code under the limitations listed in http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html#309b§97.309(b) of this Part also may be transmitted. The authorized bandwidth is 20 kHz. Anyway, a voice transmission using 5 KHz deviation has an occupied bandwidth of 16 KHz. 73, Mark N5RFX Yahoo! Groups Sponsor ~-- Everything you need is one click away. Make Yahoo! your home page now. http://us.click.yahoo.com/AHchtC/4FxNAA/yQLSAA/ELTolB/TM ~- Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [digitalradio] Re: ARRL proposal removes baud rate limitations on HF
Keep in mind there is no regulatory baud rate limit for digital voice or digital SSTV. Any emission designators with a second symbol of 1 or 2, and a third symbol of E or C are considered Phone/Image respectively. There are no baud limits for these emissions. The baud limits are for emission designators with a second symbol of 1 or 2, and a third symbol of B or D. PR Docket No 88-139 released in 1988 is the foundation of our current part 97 rules. In this docket the FCC states: We wish to recognize and encourage the experimental nature of the amateur service. It is appropriate to avoid, to the extent possible, placing in the rules detailed regulations and specifications for the configuration and operation of various amateur communications systems. Such regulations and specifications would reduce the flexibility that is a hallmark of a service free to branch out and follow an infinite number of paths This enables amateur operators to utilize their individual stations in creating and pioneering communication systems that are limited only by their personal interests, imagination and technical skills. Then under advancing the radio art the FCC states: It is our intent that amateur operators in the United States be allowed to experiment with the full range of modulation types. They go on to state: The principal use of emission designators in regulations for the amateur service is to relegate the transmission of certain inharmonious emission types to different segments of the frequency bands. The only restriction that we have with the current regulations is that in the RTTY/Data subbands we cannot mix data and image emissions; and in the Phone/Image subbands we cannot mix data with Image and phone. I think this is the biggest flaw in the current regulations and why I submitted my petition which is referenced in PR Docket 04-140 as the Miller Petition. It tries to remedy the flaw in the current regulations restricting mixing of data and image emissions. When I use the term data, I am using it with reference to emissions designators. It is interesting that you will not find a definition of data anywhere in Title 47 of the CFR. You will find what emission designators define data, but now verbal definition. 73, Mark N5RFX Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org Other areas of interest: The MixW Reflector : http://groups.yahoo.com/group/themixwgroup/ DigiPol: http://groups.yahoo.com/group/Digipol (band plan policy discussion) Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/digitalradio/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
